loplugin:nullptr (automatic rewrite)

Change-Id: I05e89f9896170d4df3d1377549ea074f06b884a0

54 files changed, 623 insertions, 623 deletions

diff --git a/vcl/source/window/abstdlg.cxx b/vcl/source/window/abstdlg.cxx
index 3ae9e30fafc7..d12d4d47d451 100644
--- a/vcl/source/window/abstdlg.cxx
+++ b/vcl/source/window/abstdlg.cxx
@@ -33,7 +33,7 @@ extern "C" VclAbstractDialogFactory* CreateDialogFactory();
 
 VclAbstractDialogFactory* VclAbstractDialogFactory::Create()
 {
-    FuncPtrCreateDialogFactory fp = 0;
+    FuncPtrCreateDialogFactory fp = nullptr;
 #if HAVE_FEATURE_DESKTOP
 #ifndef DISABLE_DYNLOADING
     static ::osl::Module aDialogLibrary;
@@ -50,7 +50,7 @@ VclAbstractDialogFactory* VclAbstractDialogFactory::Create()
 #endif
     if ( fp )
         return fp();
-    return 0;
+    return nullptr;
 }
 
 VclAbstractDialog::~VclAbstractDialog()
diff --git a/vcl/source/window/accel.cxx b/vcl/source/window/accel.cxx
index a8ce0a4ecfc5..d06e6a28ebd8 100644
--- a/vcl/source/window/accel.cxx
+++ b/vcl/source/window/accel.cxx
@@ -40,7 +40,7 @@ public:
 };
 
 sal_uInt16 ImplAccelEntryGetIndex( ImplAccelList* pList, sal_uInt16 nId,
-                               sal_uInt16* pIndex = NULL )
+                               sal_uInt16* pIndex = nullptr )
 {
     size_t  nLow;
     size_t  nHigh;
@@ -96,7 +96,7 @@ static void ImplAccelEntryInsert( ImplAccelList* pList, ImplAccelEntry* pEntry )
         do
         {
             nIndex++;
-            ImplAccelEntry* pTempEntry = NULL;
+            ImplAccelEntry* pTempEntry = nullptr;
             if ( nIndex < pList->size() )
                 pTempEntry = (*pList)[ nIndex ];
             if ( !pTempEntry || (pTempEntry->mnId != pEntry->mnId) )
@@ -147,7 +147,7 @@ void Accelerator::ImplInit()
     mnCurId             = 0;
     mnCurRepeat         = 0;
     mbIsCancel          = false;
-    mpDel               = NULL;
+    mpDel               = nullptr;
 }
 
 ImplAccelEntry* Accelerator::ImplGetAccelData( const vcl::KeyCode& rKeyCode ) const
@@ -156,7 +156,7 @@ ImplAccelEntry* Accelerator::ImplGetAccelData( const vcl::KeyCode& rKeyCode ) co
     if( it != mpData->maKeyMap.end() )
         return it->second;
     else
-        return NULL;
+        return nullptr;
 }
 
 void Accelerator::ImplCopyData( ImplAccelData& rAccelData )
@@ -173,7 +173,7 @@ void Accelerator::ImplCopyData( ImplAccelData& rAccelData )
             pEntry->mpAutoAccel = pEntry->mpAccel;
         }
         else
-            pEntry->mpAutoAccel = NULL;
+            pEntry->mpAutoAccel = nullptr;
 
         mpData->maKeyMap.insert( std::make_pair( pEntry->maKeyCode.GetFullCode(), pEntry ) );
         mpData->maIdList.push_back( pEntry );
@@ -310,7 +310,7 @@ void Accelerator::Select()
 
 void Accelerator::InsertItem( sal_uInt16 nItemId, const vcl::KeyCode& rKeyCode )
 {
-    ImplInsertAccel( nItemId, rKeyCode, true, NULL );
+    ImplInsertAccel( nItemId, rKeyCode, true, nullptr );
 }
 
 void Accelerator::InsertItem( const ResId& rResId )
@@ -320,7 +320,7 @@ void Accelerator::InsertItem( const ResId& rResId )
     sal_uInt16              nAccelKeyId;
     sal_uInt16              bDisable;
     vcl::KeyCode            aKeyCode;
-    Accelerator*        pAutoAccel  = NULL;
+    Accelerator*        pAutoAccel  = nullptr;
 
     GetRes( rResId.SetRT( RSC_ACCELITEM ) );
     nObjMask        = ReadLongRes();
@@ -364,7 +364,7 @@ vcl::KeyCode Accelerator::GetKeyCode( sal_uInt16 nItemId ) const
 sal_uInt16 Accelerator::GetItemId( sal_uInt16 nPos ) const
 {
 
-    ImplAccelEntry* pEntry = ( nPos < mpData->maIdList.size() ) ? mpData->maIdList[ nPos ] : NULL;
+    ImplAccelEntry* pEntry = ( nPos < mpData->maIdList.size() ) ? mpData->maIdList[ nPos ] : nullptr;
     if ( pEntry )
         return pEntry->mnId;
     else
@@ -378,7 +378,7 @@ Accelerator* Accelerator::GetAccel( sal_uInt16 nItemId ) const
     if ( nIndex != ACCELENTRY_NOTFOUND )
         return mpData->maIdList[ nIndex ]->mpAccel;
     else
-        return NULL;
+        return nullptr;
 }
 
 Accelerator& Accelerator::operator=( const Accelerator& rAccel )
diff --git a/vcl/source/window/accessibility.cxx b/vcl/source/window/accessibility.cxx
index 5b79b92e82cd..e0a708f78ff9 100644
--- a/vcl/source/window/accessibility.cxx
+++ b/vcl/source/window/accessibility.cxx
@@ -109,11 +109,11 @@ using ::com::sun::star::awt::XTopWindow;
 ImplAccessibleInfos::ImplAccessibleInfos()
 {
     nAccessibleRole = 0xFFFF;
-    pAccessibleName = NULL;
-    pAccessibleDescription = NULL;
-    pLabeledByWindow = NULL;
-    pLabelForWindow = NULL;
-    pMemberOfWindow = NULL;
+    pAccessibleName = nullptr;
+    pAccessibleDescription = nullptr;
+    pLabeledByWindow = nullptr;
+    pLabelForWindow = nullptr;
+    pMemberOfWindow = nullptr;
 }
 
 ImplAccessibleInfos::~ImplAccessibleInfos()
@@ -215,13 +215,13 @@ vcl::Window* Window::ImplGetAccessibleCandidateChild( sal_uInt16 nChild, sal_uIn
         rChildCount++;
     }
 
-    return NULL;
+    return nullptr;
 }
 
 vcl::Window* Window::GetAccessibleParentWindow() const
 {
     if ( ImplIsAccessibleNativeFrame() )
-        return NULL;
+        return nullptr;
 
     vcl::Window* pParent = mpWindowImpl->mpParent;
     if( GetType() == WINDOW_MENUBARWINDOW )
@@ -620,7 +620,7 @@ vcl::Window* Window::GetAccessibleRelationMemberOf() const
     if (!isContainerWindow(this) && !isContainerWindow(GetParent()))
         return getLegacyNonLayoutAccessibleRelationMemberOf();
 
-    return NULL;
+    return nullptr;
 }
 
 vcl::Window* Window::getAccessibleRelationLabelFor() const
@@ -628,7 +628,7 @@ vcl::Window* Window::getAccessibleRelationLabelFor() const
     if (mpWindowImpl->mpAccessibleInfos && mpWindowImpl->mpAccessibleInfos->pLabelForWindow)
         return mpWindowImpl->mpAccessibleInfos->pLabelForWindow;
 
-    return NULL;
+    return nullptr;
 }
 
 vcl::Window* Window::GetAccessibleRelationLabelFor() const
@@ -641,7 +641,7 @@ vcl::Window* Window::GetAccessibleRelationLabelFor() const
     if (!isContainerWindow(this) && !isContainerWindow(GetParent()))
         return getLegacyNonLayoutAccessibleRelationLabelFor();
 
-    return NULL;
+    return nullptr;
 }
 
 vcl::Window* Window::GetAccessibleRelationLabeledBy() const
@@ -665,7 +665,7 @@ vcl::Window* Window::GetAccessibleRelationLabeledBy() const
     if (!isContainerWindow(this) && !isContainerWindow(GetParent()))
         return getLegacyNonLayoutAccessibleRelationLabeledBy();
 
-    return NULL;
+    return nullptr;
 }
 
 bool Window::IsAccessibilityEventsSuppressed( bool bTraverseParentPath )
diff --git a/vcl/source/window/accmgr.cxx b/vcl/source/window/accmgr.cxx
index b94e8c062414..295a1681d40a 100644
--- a/vcl/source/window/accmgr.cxx
+++ b/vcl/source/window/accmgr.cxx
@@ -90,12 +90,12 @@ void ImplAccelManager::EndSequence()
     {
         Accelerator* pTempAccel = (*mpSequenceList)[ i ];
         pTempAccel->mbIsCancel = false;
-        pTempAccel->mpDel = NULL;
+        pTempAccel->mpDel = nullptr;
     }
 
     // delete sequence-list
     delete mpSequenceList;
-    mpSequenceList = NULL;
+    mpSequenceList = nullptr;
 }
 
 bool ImplAccelManager::IsAccelKey( const vcl::KeyCode& rKeyCode, sal_uInt16 nRepeat )
@@ -111,7 +111,7 @@ bool ImplAccelManager::IsAccelKey( const vcl::KeyCode& rKeyCode, sal_uInt16 nRep
     // are we in a sequence ?
     if ( mpSequenceList )
     {
-        pAccel = mpSequenceList->empty() ? NULL : (*mpSequenceList)[ 0 ];
+        pAccel = mpSequenceList->empty() ? nullptr : (*mpSequenceList)[ 0 ];
 
         // not found ?
         if ( !pAccel )
@@ -160,7 +160,7 @@ bool ImplAccelManager::IsAccelKey( const vcl::KeyCode& rKeyCode, sal_uInt16 nRep
                         pAccel->maCurKeyCode    = vcl::KeyCode();
                         pAccel->mnCurId         = 0;
                         pAccel->mnCurRepeat     = 0;
-                        pAccel->mpDel           = NULL;
+                        pAccel->mpDel           = nullptr;
                     }
 
                     return true;
@@ -230,7 +230,7 @@ bool ImplAccelManager::IsAccelKey( const vcl::KeyCode& rKeyCode, sal_uInt16 nRep
                         pAccel->maCurKeyCode    = vcl::KeyCode();
                         pAccel->mnCurId         = 0;
                         pAccel->mnCurRepeat     = 0;
-                        pAccel->mpDel           = NULL;
+                        pAccel->mpDel           = nullptr;
                     }
 
                     return true;
diff --git a/vcl/source/window/brdwin.cxx b/vcl/source/window/brdwin.cxx
index adb0621ab66b..f65e69ec26d7 100644
--- a/vcl/source/window/brdwin.cxx
+++ b/vcl/source/window/brdwin.cxx
@@ -442,7 +442,7 @@ void ImplNoBorderWindowView::DrawWindow(vcl::RenderContext&, sal_uInt16, const P
 // - ImplSmallBorderWindowView -
 ImplSmallBorderWindowView::ImplSmallBorderWindowView( ImplBorderWindow* pBorderWindow )
     : mpBorderWindow(pBorderWindow)
-    , mpOutDev(NULL)
+    , mpOutDev(nullptr)
     , mnWidth(0)
     , mnHeight(0)
     , mnLeftBorder(0)
@@ -460,7 +460,7 @@ void ImplSmallBorderWindowView::Init( OutputDevice* pDev, long nWidth, long nHei
     mnHeight    = nHeight;
     mbNWFBorder = false;
 
-    vcl::Window *pWin = NULL, *pCtrl = NULL;
+    vcl::Window *pWin = nullptr, *pCtrl = nullptr;
     if (mpOutDev->GetOutDevType() == OUTDEV_WINDOW)
         pWin = static_cast<vcl::Window*>(mpOutDev.get());
 
@@ -552,7 +552,7 @@ void ImplSmallBorderWindowView::Init( OutputDevice* pDev, long nWidth, long nHei
                         mpBorderWindow->SetBackground();
                         pCtrl->SetPaintTransparent( true );
 
-                        vcl::Window* pCompoundParent = NULL;
+                        vcl::Window* pCompoundParent = nullptr;
                         if( pWin->GetParent() && pWin->GetParent()->IsCompoundControl() )
                             pCompoundParent = pWin->GetParent();
 
@@ -805,8 +805,8 @@ ImplStdBorderWindowView::ImplStdBorderWindowView( ImplBorderWindow* pBorderWindo
     maFrameData.mnHelpState     = DrawButtonFlags::NONE;
     maFrameData.mbTitleClipped  = false;
 
-    mpATitleVirDev              = NULL;
-    mpDTitleVirDev              = NULL;
+    mpATitleVirDev              = nullptr;
+    mpDTitleVirDev              = nullptr;
 }
 
 ImplStdBorderWindowView::~ImplStdBorderWindowView()
@@ -1728,7 +1728,7 @@ void ImplBorderWindow::ImplInit( vcl::Window* pParent,
                                  WinBits nStyle, sal_uInt16 nTypeStyle,
                                  const ::com::sun::star::uno::Any& )
 {
-    ImplInit( pParent, nStyle, nTypeStyle, NULL );
+    ImplInit( pParent, nStyle, nTypeStyle, nullptr );
 }
 
 void ImplBorderWindow::ImplInit( vcl::Window* pParent,
@@ -1786,7 +1786,7 @@ void ImplBorderWindow::ImplInit( vcl::Window* pParent,
     SetBackground();
     SetTextFillColor();
 
-    mpMenuBarWindow = NULL;
+    mpMenuBarWindow = nullptr;
     mnMinWidth      = 0;
     mnMinHeight     = 0;
     mnMaxWidth      = SHRT_MAX;
@@ -1832,7 +1832,7 @@ ImplBorderWindow::~ImplBorderWindow()
 void ImplBorderWindow::dispose()
 {
     delete mpBorderView;
-    mpBorderView = NULL;
+    mpBorderView = nullptr;
     mpMenuBarWindow.clear();
     mpNotebookBarWindow.disposeAndClear();
     vcl::Window::dispose();
diff --git a/vcl/source/window/btndlg.cxx b/vcl/source/window/btndlg.cxx
index ec9589aea781..6ad603ab1a76 100644
--- a/vcl/source/window/btndlg.cxx
+++ b/vcl/source/window/btndlg.cxx
@@ -101,7 +101,7 @@ ImplBtnDlgItem* ButtonDialog::ImplGetItem( sal_uInt16 nId ) const
             return &(*it);
     }
 
-    return NULL;
+    return nullptr;
 }
 
 long ButtonDialog::ImplGetButtonSize()
@@ -236,7 +236,7 @@ void ButtonDialog::StateChanged( StateChangedType nType )
         for (auto & it : m_ItemList)
         {
             if ( it->mpPushButton && it->mbOwnButton )
-                it->mpPushButton->SetZOrder(0, ZOrderFlags::Last);
+                it->mpPushButton->SetZOrder(nullptr, ZOrderFlags::Last);
         }
 
         // Set focus on default button.
@@ -366,7 +366,7 @@ PushButton* ButtonDialog::GetPushButton( sal_uInt16 nId ) const
     if ( pItem )
         return pItem->mpPushButton;
     else
-        return NULL;
+        return nullptr;
 }
 
 void ButtonDialog::SetButtonText( sal_uInt16 nId, const OUString& rText )
diff --git a/vcl/source/window/builder.cxx b/vcl/source/window/builder.cxx
index f16d439f1bb5..e39eb6f8435f 100644
--- a/vcl/source/window/builder.cxx
+++ b/vcl/source/window/builder.cxx
@@ -376,9 +376,9 @@ VclBuilder::VclBuilder(vcl::Window *pParent, const OUString& sUIDir, const OUStr
     for (std::vector<ButtonImageWidgetMap>::iterator aI = m_pParserState->m_aButtonImageWidgetMaps.begin(),
          aEnd = m_pParserState->m_aButtonImageWidgetMaps.end(); aI != aEnd; ++aI)
     {
-        PushButton *pTargetButton = NULL;
-        RadioButton *pTargetRadio = NULL;
-        Button *pTarget = NULL;
+        PushButton *pTargetButton = nullptr;
+        RadioButton *pTargetRadio = nullptr;
+        Button *pTarget = nullptr;
 
         if (!aI->m_bRadio)
         {
@@ -1851,7 +1851,7 @@ VclPtr<vcl::Window> VclBuilder::insertObject(vcl::Window *pParent, const OString
         //deferred due to waiting to encounter it in this .ui, and it hasn't
         //been seen yet, then make unattached widgets parent-less toplevels
         if (pParent == m_pParent.get() && m_bToplevelHasDeferredInit)
-            pParent = NULL;
+            pParent = nullptr;
         pCurrentChild = makeObject(pParent, rClass, rID, rProps);
     }
 
@@ -2029,7 +2029,7 @@ bool VclBuilder::sortIntoBestTabTraversalOrder::operator()(const vcl::Window *pA
 
 void VclBuilder::handleChild(vcl::Window *pParent, xmlreader::XmlReader &reader)
 {
-    vcl::Window *pCurrentChild = NULL;
+    vcl::Window *pCurrentChild = nullptr;
 
     xmlreader::Span name;
     int nsId;
@@ -2102,7 +2102,7 @@ void VclBuilder::handleChild(vcl::Window *pParent, xmlreader::XmlReader &reader)
                         else if (sInternalChild.startsWith("action_area") || sInternalChild.startsWith("messagedialog-action_area"))
                         {
                             vcl::Window *pContentArea = pCurrentChild->GetParent();
-                            if (Dialog *pBoxParent = dynamic_cast<Dialog*>(pContentArea ? pContentArea->GetParent() : NULL))
+                            if (Dialog *pBoxParent = dynamic_cast<Dialog*>(pContentArea ? pContentArea->GetParent() : nullptr))
                             {
                                 pBoxParent->set_action_area(static_cast<VclButtonBox*>(pCurrentChild)); // FIXME-VCLPTR
                             }
@@ -2117,7 +2117,7 @@ void VclBuilder::handleChild(vcl::Window *pParent, xmlreader::XmlReader &reader)
                             aChilds.push_back(pChild);
                         }
 
-                        bool bIsButtonBox = dynamic_cast<VclButtonBox*>(pCurrentChild) != NULL;
+                        bool bIsButtonBox = dynamic_cast<VclButtonBox*>(pCurrentChild) != nullptr;
 
                         //sort child order within parent so that tabbing
                         //between controls goes in a visually sensible sequence
@@ -2945,12 +2945,12 @@ VclPtr<vcl::Window> VclBuilder::handleObject(vcl::Window *pParent, xmlreader::Xm
     if (sClass == "GtkAdjustment")
     {
         handleAdjustment(sID, aProperties);
-        return NULL;
+        return nullptr;
     }
     else if (sClass == "GtkTextBuffer")
     {
         handleTextBuffer(sID, aProperties);
-        return NULL;
+        return nullptr;
     }
 
     if (!pCurrentChild)
@@ -3010,7 +3010,7 @@ void VclBuilder::applyPackingProperty(vcl::Window *pCurrent,
 
     //ToolBoxItems are not true widgets just elements
     //of the ToolBox itself
-    ToolBox *pToolBoxParent = NULL;
+    ToolBox *pToolBoxParent = nullptr;
     if (pCurrent == pParent)
         pToolBoxParent = dynamic_cast<ToolBox*>(pParent);
 
@@ -3217,7 +3217,7 @@ void VclBuilder::collectAccelerator(xmlreader::XmlReader &reader, stringmap &rMa
 
 vcl::Window *VclBuilder::get_widget_root()
 {
-    return m_aChildren.empty() ? NULL : m_aChildren[0].m_pWindow.get();
+    return m_aChildren.empty() ? nullptr : m_aChildren[0].m_pWindow.get();
 }
 
 vcl::Window *VclBuilder::get_by_name(const OString& sID)
@@ -3229,7 +3229,7 @@ vcl::Window *VclBuilder::get_by_name(const OString& sID)
             return aI->m_pWindow;
     }
 
-    return NULL;
+    return nullptr;
 }
 
 PopupMenu *VclBuilder::get_menu(const OString& sID)
@@ -3241,7 +3241,7 @@ PopupMenu *VclBuilder::get_menu(const OString& sID)
             return aI->m_pMenu;
     }
 
-    return NULL;
+    return nullptr;
 }
 
 short VclBuilder::get_response(const vcl::Window *pWindow) const
@@ -3355,7 +3355,7 @@ const VclBuilder::ListStore *VclBuilder::get_model_by_name(const OString& sID) c
     std::map<OString, ListStore>::const_iterator aI = m_pParserState->m_aModels.find(sID);
     if (aI != m_pParserState->m_aModels.end())
         return &(aI->second);
-    return NULL;
+    return nullptr;
 }
 
 const VclBuilder::TextBuffer *VclBuilder::get_buffer_by_name(const OString& sID) const
@@ -3363,7 +3363,7 @@ const VclBuilder::TextBuffer *VclBuilder::get_buffer_by_name(const OString& sID)
     std::map<OString, TextBuffer>::const_iterator aI = m_pParserState->m_aTextBuffers.find(sID);
     if (aI != m_pParserState->m_aTextBuffers.end())
         return &(aI->second);
-    return NULL;
+    return nullptr;
 }
 
 const VclBuilder::Adjustment *VclBuilder::get_adjustment_by_name(const OString& sID) const
@@ -3371,7 +3371,7 @@ const VclBuilder::Adjustment *VclBuilder::get_adjustment_by_name(const OString&
     std::map<OString, Adjustment>::const_iterator aI = m_pParserState->m_aAdjustments.find(sID);
     if (aI != m_pParserState->m_aAdjustments.end())
         return &(aI->second);
-    return NULL;
+    return nullptr;
 }
 
 void VclBuilder::mungeModel(ListBox &rTarget, const ListStore &rStore, sal_uInt16 nActiveId)
diff --git a/vcl/source/window/cairo_cairo.cxx b/vcl/source/window/cairo_cairo.cxx
index a722c2e8d073..54b27dc98cf7 100644
--- a/vcl/source/window/cairo_cairo.cxx
+++ b/vcl/source/window/cairo_cairo.cxx
@@ -35,7 +35,7 @@ namespace cairo
 
     const SystemEnvData* GetSysData(const vcl::Window *pOutputWindow)
     {
-        const SystemEnvData* pSysData = NULL;
+        const SystemEnvData* pSysData = nullptr;
         // check whether we're a SysChild: have to fetch system data
         // directly from SystemChildWindow, because the GetSystemData
         // method is unfortunately not virtual
diff --git a/vcl/source/window/clipping.cxx b/vcl/source/window/clipping.cxx
index 9b088c3fa868..41ed2cb6d786 100644
--- a/vcl/source/window/clipping.cxx
+++ b/vcl/source/window/clipping.cxx
@@ -274,7 +274,7 @@ void Window::ImplInitWinChildClipRegion()
         if ( mpWindowImpl->mpChildClipRegion )
         {
             delete mpWindowImpl->mpChildClipRegion;
-            mpWindowImpl->mpChildClipRegion = NULL;
+            mpWindowImpl->mpChildClipRegion = nullptr;
         }
     }
     else
@@ -375,7 +375,7 @@ bool Window::ImplSysObjClip( const vcl::Region* pOldRegion )
 void Window::ImplUpdateSysObjChildrenClip()
 {
     if ( mpWindowImpl->mpSysObj && mpWindowImpl->mbInitWinClipRegion )
-        ImplSysObjClip( NULL );
+        ImplSysObjClip( nullptr );
 
     vcl::Window* pWindow = mpWindowImpl->mpFirstChild;
     while ( pWindow )
@@ -423,7 +423,7 @@ bool Window::ImplSetClipFlagChildren( bool bSysObjOnlySmaller )
     bool bUpdate = true;
     if ( mpWindowImpl->mpSysObj )
     {
-        vcl::Region* pOldRegion = NULL;
+        vcl::Region* pOldRegion = nullptr;
         if ( bSysObjOnlySmaller && !mpWindowImpl->mbInitWinClipRegion )
             pOldRegion = new vcl::Region( mpWindowImpl->maWinClipRegion );
 
@@ -898,7 +898,7 @@ void Window::ImplDeleteOverlapBackground()
         if ( mpWindowImpl->mpOverlapData->mpSaveBackRgn )
         {
             delete mpWindowImpl->mpOverlapData->mpSaveBackRgn;
-            mpWindowImpl->mpOverlapData->mpSaveBackRgn = NULL;
+            mpWindowImpl->mpOverlapData->mpSaveBackRgn = nullptr;
         }
 
         // remove window from the list
@@ -911,7 +911,7 @@ void Window::ImplDeleteOverlapBackground()
                 pTemp = pTemp->mpWindowImpl->mpOverlapData->mpNextBackWin;
             pTemp->mpWindowImpl->mpOverlapData->mpNextBackWin = mpWindowImpl->mpOverlapData->mpNextBackWin;
         }
-        mpWindowImpl->mpOverlapData->mpNextBackWin = NULL;
+        mpWindowImpl->mpOverlapData->mpNextBackWin = nullptr;
     }
 }
 
diff --git a/vcl/source/window/cmdevt.cxx b/vcl/source/window/cmdevt.cxx
index 803d7e24f64a..1af5431a5c66 100644
--- a/vcl/source/window/cmdevt.cxx
+++ b/vcl/source/window/cmdevt.cxx
@@ -32,7 +32,7 @@ CommandExtTextInputData::CommandExtTextInputData( const OUString& rText,
         memcpy( mpTextAttr, pTextAttr, maText.getLength()*sizeof(sal_uInt16) );
     }
     else
-        mpTextAttr = NULL;
+        mpTextAttr = nullptr;
     mnCursorPos     = nCursorPos;
     mnCursorFlags   = nCursorFlags;
     mbOnlyCursor    = bOnlyCursor;
@@ -47,7 +47,7 @@ CommandExtTextInputData::CommandExtTextInputData( const CommandExtTextInputData&
         memcpy( mpTextAttr, rData.mpTextAttr, maText.getLength()*sizeof(sal_uInt16) );
     }
     else
-        mpTextAttr = NULL;
+        mpTextAttr = nullptr;
     mnCursorPos     = rData.mnCursorPos;
     mnCursorFlags   = rData.mnCursorFlags;
     mbOnlyCursor    = rData.mbOnlyCursor;
diff --git a/vcl/source/window/cursor.cxx b/vcl/source/window/cursor.cxx
index 5a01d10e676a..738ff0d3418c 100644
--- a/vcl/source/window/cursor.cxx
+++ b/vcl/source/window/cursor.cxx
@@ -175,7 +175,7 @@ void vcl::Cursor::ImplDoShow( bool bDrawDirect, bool bRestore )
             pWindow = Application::GetFocusWindow();
             if ( !pWindow || (pWindow->mpWindowImpl->mpCursor != this) || pWindow->mpWindowImpl->mbInPaint
                 || !pWindow->mpWindowImpl->mpFrameData->mbHasFocus )
-                pWindow = NULL;
+                pWindow = nullptr;
         }
 
         if ( pWindow )
@@ -216,7 +216,7 @@ bool vcl::Cursor::ImplDoHide( bool bSuspend )
         if ( !bSuspend )
         {
             mpData->maTimer.Stop();
-            mpData->mpWindow = NULL;
+            mpData->mpWindow = nullptr;
         }
     }
     return bWasCurVisible;
@@ -269,8 +269,8 @@ IMPL_LINK_NOARG_TYPED(vcl::Cursor, ImplTimerHdl, Timer *, void)
 
 vcl::Cursor::Cursor()
 {
-    mpData          = NULL;
-    mpWindow        = NULL;
+    mpData          = nullptr;
+    mpWindow        = nullptr;
     mnSlant         = 0;
     mnOrientation   = 0;
     mnDirection     = CursorDirection::NONE;
@@ -282,8 +282,8 @@ vcl::Cursor::Cursor( const Cursor& rCursor ) :
     maSize( rCursor.maSize ),
     maPos( rCursor.maPos )
 {
-    mpData          = NULL;
-    mpWindow        = NULL;
+    mpData          = nullptr;
+    mpWindow        = nullptr;
     mnSlant         = rCursor.mnSlant;
     mnOrientation   = rCursor.mnOrientation;
     mnDirection     = rCursor.mnDirection;
diff --git a/vcl/source/window/debug.cxx b/vcl/source/window/debug.cxx
index e1d48fc876e7..baa370027022 100644
--- a/vcl/source/window/debug.cxx
+++ b/vcl/source/window/debug.cxx
@@ -41,7 +41,7 @@ const char* ImplDbgCheckWindow( const void* pObj )
         pChild = pChild->mpWindowImpl->mpNext;
     }
 
-    return NULL;
+    return nullptr;
 }
 #endif
 
diff --git a/vcl/source/window/debugevent.cxx b/vcl/source/window/debugevent.cxx
index 11d17daa8f2a..e57b06b35db8 100644
--- a/vcl/source/window/debugevent.cxx
+++ b/vcl/source/window/debugevent.cxx
@@ -49,7 +49,7 @@ vcl::Window *DebugEventInjector::ChooseWindow()
         if (!(pParent = Application::GetTopWindow( nIdx )))
             pParent = static_cast<vcl::Window *>(Application::GetAppWindow());
     }
-    assert (pParent != NULL);
+    assert (pParent != nullptr);
 
     std::vector< vcl::Window *> aChildren;
     pParent->CollectChildren( aChildren );
@@ -104,7 +104,7 @@ void DebugEventInjector::InjectMenuEvent()
 
     sal_uInt16 nEvent = nEvents[ (int)(getRandom() * SAL_N_ELEMENTS( nEvents )) ];
     SalMenuEvent aEvent = aIds[ getRandom() * aIds.size() ];
-    bool bHandled = ImplWindowFrameProc( pSysWin, NULL, nEvent, &aEvent);
+    bool bHandled = ImplWindowFrameProc( pSysWin, nullptr, nEvent, &aEvent);
 
     SAL_INFO( "vcl.debugevent",
               "Injected menu event " << aEvent.mpMenu
@@ -160,14 +160,14 @@ void DebugEventInjector::InjectTextEvent()
     if( getRandom() < 0.05 ) // modifier
         aKeyEvent.mnCode |= (sal_uInt16)( getRandom() * KEY_MODIFIERS_MASK ) & KEY_MODIFIERS_MASK;
 
-    bool bHandled = ImplWindowFrameProc( pWindow, NULL, SALEVENT_KEYINPUT, &aKeyEvent);
+    bool bHandled = ImplWindowFrameProc( pWindow, nullptr, SALEVENT_KEYINPUT, &aKeyEvent);
 
     SAL_INFO( "vcl.debugevent",
               "Injected key 0x" << std::hex << (int) aKeyEvent.mnCode << std::dec
               << " -> " << bHandled
               << " win " << pWindow );
 
-    ImplWindowFrameProc( pWindow, NULL, SALEVENT_KEYUP, &aKeyEvent );
+    ImplWindowFrameProc( pWindow, nullptr, SALEVENT_KEYUP, &aKeyEvent );
 }
 
 /*
@@ -242,13 +242,13 @@ void DebugEventInjector::InjectKeyNavEdit()
 
     aKeyEvent.mnCharCode = 0x0; // hopefully unused.
 
-    bool bHandled = ImplWindowFrameProc( pWindow, NULL, SALEVENT_KEYINPUT, &aKeyEvent );
+    bool bHandled = ImplWindowFrameProc( pWindow, nullptr, SALEVENT_KEYINPUT, &aKeyEvent );
 
     SAL_INFO( "vcl.debugevent",
               "Injected edit / move key 0x" << std::hex << (int) aKeyEvent.mnCode << std::dec
               << " -> " << bHandled
               << " win " <<  pWindow );
-    ImplWindowFrameProc( pWindow, NULL, SALEVENT_KEYUP, &aKeyEvent );
+    ImplWindowFrameProc( pWindow, nullptr, SALEVENT_KEYUP, &aKeyEvent );
 }
 
 void DebugEventInjector::Invoke()
@@ -269,12 +269,12 @@ DebugEventInjector *DebugEventInjector::getCreate()
     sal_uInt32 nEvents;
     const char *pEvents = getenv("VCL_EVENT_INJECTION");
     if (!pEvents)
-        return NULL;
+        return nullptr;
     nEvents = OString( pEvents ).toUInt32();
     if (nEvents > 0)
         return new DebugEventInjector( nEvents );
     else
-        return NULL;
+        return nullptr;
 }
 
 #endif // OSL_DEBUG_LEVEL > 0
diff --git a/vcl/source/window/decoview.cxx b/vcl/source/window/decoview.cxx
index 376c7bf2bb4e..538c6b1d9573 100644
--- a/vcl/source/window/decoview.cxx
+++ b/vcl/source/window/decoview.cxx
@@ -623,7 +623,7 @@ void ImplDrawButton( OutputDevice *const pDev, Rectangle aFillRect,
 void ImplDrawFrame( OutputDevice *const pDev, Rectangle& rRect,
                     const StyleSettings& rStyleSettings, DrawFrameStyle nStyle, DrawFrameFlags nFlags )
 {
-    vcl::Window *const pWin = (pDev->GetOutDevType()==OUTDEV_WINDOW) ? static_cast<vcl::Window*>(pDev) : NULL;
+    vcl::Window *const pWin = (pDev->GetOutDevType()==OUTDEV_WINDOW) ? static_cast<vcl::Window*>(pDev) : nullptr;
 
     const bool bMenuStyle(nFlags & DrawFrameFlags::Menu);
 
@@ -683,7 +683,7 @@ void ImplDrawFrame( OutputDevice *const pDev, Rectangle& rRect,
 
         if ( bNoDraw )
         {
-            ImplDrawDPILineRect( pDev, rRect, NULL, bRound );
+            ImplDrawDPILineRect( pDev, rRect, nullptr, bRound );
         }
         else
         {
@@ -1055,7 +1055,7 @@ void DecorationView::DrawSeparator( const Point& rStart, const Point& rStop, boo
 {
     Point aStart( rStart ), aStop( rStop );
     const StyleSettings& rStyleSettings = mpOutDev->GetSettings().GetStyleSettings();
-    vcl::Window *const pWin = (mpOutDev->GetOutDevType()==OUTDEV_WINDOW) ? static_cast<vcl::Window*>(mpOutDev.get()) : NULL;
+    vcl::Window *const pWin = (mpOutDev->GetOutDevType()==OUTDEV_WINDOW) ? static_cast<vcl::Window*>(mpOutDev.get()) : nullptr;
     if(pWin)
     {
         ControlPart nPart = ( bVertical ? PART_SEPARATOR_VERT : PART_SEPARATOR_HORZ );
diff --git a/vcl/source/window/dialog.cxx b/vcl/source/window/dialog.cxx
index ea24882f7bba..c98270cf38e8 100644
--- a/vcl/source/window/dialog.cxx
+++ b/vcl/source/window/dialog.cxx
@@ -135,9 +135,9 @@ vcl::Window * nextLogicalChildOfParent(vcl::Window *pTopLevel, vcl::Window *pChi
     {
         vcl::Window *pParent = pLastChild->GetParent();
         if (!pParent)
-            return NULL;
+            return nullptr;
         if (pParent == pTopLevel)
-            return NULL;
+            return nullptr;
         pLastChild = pParent;
         pChild = pParent->GetWindow(GetWindowType::Next);
     }
@@ -161,9 +161,9 @@ vcl::Window * prevLogicalChildOfParent(vcl::Window *pTopLevel, vcl::Window *pChi
     {
         vcl::Window *pParent = pLastChild->GetParent();
         if (!pParent)
-            return NULL;
+            return nullptr;
         if (pParent == pTopLevel)
-            return NULL;
+            return nullptr;
         pLastChild = pParent;
         pChild = pParent->GetWindow(GetWindowType::Prev);
     }
@@ -237,7 +237,7 @@ void ImplWindowAutoMnemonic( vcl::Window* pWindow )
 
 static VclButtonBox* getActionArea(Dialog *pDialog)
 {
-    VclButtonBox *pButtonBox = NULL;
+    VclButtonBox *pButtonBox = nullptr;
     if (pDialog->isLayoutEnabled())
     {
         vcl::Window *pBox = pDialog->GetWindow(GetWindowType::FirstChild);
@@ -276,7 +276,7 @@ static PushButton* ImplGetDefaultButton( Dialog* pDialog )
         pChild = pChild->GetWindow( GetWindowType::Next );
     }
 
-    return NULL;
+    return nullptr;
 }
 
 static PushButton* ImplGetOKButton( Dialog* pDialog )
@@ -290,7 +290,7 @@ static PushButton* ImplGetOKButton( Dialog* pDialog )
         pChild = pChild->GetWindow( GetWindowType::Next );
     }
 
-    return NULL;
+    return nullptr;
 }
 
 static PushButton* ImplGetCancelButton( Dialog* pDialog )
@@ -305,7 +305,7 @@ static PushButton* ImplGetCancelButton( Dialog* pDialog )
         pChild = pChild->GetWindow( GetWindowType::Next );
     }
 
-    return NULL;
+    return nullptr;
 }
 
 static void ImplMouseAutoPos( Dialog* pDialog )
@@ -342,7 +342,7 @@ struct DialogImpl
 void Dialog::ImplInitDialogData()
 {
     mpWindowImpl->mbDialog  = true;
-    mpPrevExecuteDlg        = NULL;
+    mpPrevExecuteDlg        = nullptr;
     mbInExecute             = false;
     mbOldSaveBack           = false;
     mbInClose               = false;
@@ -365,7 +365,7 @@ void Dialog::ImplInit( vcl::Window* pParent, WinBits nStyle, InitFlag eFlag )
     nStyle |= WB_SYSTEMWINDOW;
 
     if (eFlag == InitFlag::NoParent)
-        pParent = NULL;
+        pParent = nullptr;
     else if (!pParent) // parent is NULL: get the default Dialog parent
     {
         pParent = Application::GetDefDialogParent();
@@ -402,7 +402,7 @@ void Dialog::ImplInit( vcl::Window* pParent, WinBits nStyle, InitFlag eFlag )
         if ( (nStyle & (WB_BORDER | WB_NOBORDER | WB_MOVEABLE | WB_SIZEABLE | WB_CLOSEABLE)) == WB_BORDER )
         {
             VclPtrInstance<ImplBorderWindow> pBorderWin( pParent, nStyle, BORDERWINDOW_STYLE_FRAME );
-            SystemWindow::ImplInit( pBorderWin, nStyle & ~WB_BORDER, NULL );
+            SystemWindow::ImplInit( pBorderWin, nStyle & ~WB_BORDER, nullptr );
             pBorderWin->mpWindowImpl->mpClientWindow = this;
             pBorderWin->GetBorder( mpWindowImpl->mnLeftBorder, mpWindowImpl->mnTopBorder, mpWindowImpl->mnRightBorder, mpWindowImpl->mnBottomBorder );
             mpWindowImpl->mpBorderWindow  = pBorderWin;
@@ -412,7 +412,7 @@ void Dialog::ImplInit( vcl::Window* pParent, WinBits nStyle, InitFlag eFlag )
         {
             mpWindowImpl->mbFrame         = true;
             mpWindowImpl->mbOverlapWin    = true;
-            SystemWindow::ImplInit( pParent, (nStyle & (WB_MOVEABLE | WB_SIZEABLE | WB_ROLLABLE | WB_CLOSEABLE | WB_STANDALONE)) | WB_CLOSEABLE, NULL );
+            SystemWindow::ImplInit( pParent, (nStyle & (WB_MOVEABLE | WB_SIZEABLE | WB_ROLLABLE | WB_CLOSEABLE | WB_STANDALONE)) | WB_CLOSEABLE, nullptr );
             // Now set all style bits
             mpWindowImpl->mnStyle = nStyle;
         }
@@ -420,7 +420,7 @@ void Dialog::ImplInit( vcl::Window* pParent, WinBits nStyle, InitFlag eFlag )
     else
     {
         VclPtrInstance<ImplBorderWindow> pBorderWin( pParent, nStyle, BORDERWINDOW_STYLE_OVERLAP | BORDERWINDOW_STYLE_BORDER );
-        SystemWindow::ImplInit( pBorderWin, nStyle & ~WB_BORDER, NULL );
+        SystemWindow::ImplInit( pBorderWin, nStyle & ~WB_BORDER, nullptr );
         pBorderWin->mpWindowImpl->mpClientWindow = this;
         pBorderWin->GetBorder( mpWindowImpl->mnLeftBorder, mpWindowImpl->mnTopBorder, mpWindowImpl->mnRightBorder, mpWindowImpl->mnBottomBorder );
         mpWindowImpl->mpBorderWindow  = pBorderWin;
@@ -508,7 +508,7 @@ OUString VclBuilderContainer::getUIRootDir()
 void Dialog::doDeferredInit(WinBits nBits)
 {
     VclPtr<vcl::Window> pParent = mpDialogParent;
-    mpDialogParent = NULL;
+    mpDialogParent = nullptr;
     ImplInit(pParent, nBits, mnInitFlag);
     mbIsDefferedInit = false;
 }
@@ -572,7 +572,7 @@ Dialog::~Dialog()
 void Dialog::dispose()
 {
     delete mpDialogImpl;
-    mpDialogImpl = NULL;
+    mpDialogImpl = nullptr;
     mpPrevExecuteDlg.clear();
     mpActionArea.clear();
     mpContentArea.clear();
@@ -955,7 +955,7 @@ void Dialog::EndDialog( long nResult )
                 mpPrevExecuteDlg->GrabFocus();
             }
         }
-        mpPrevExecuteDlg = NULL;
+        mpPrevExecuteDlg = nullptr;
 
         Hide();
         EnableSaveBackground( mbOldSaveBack );
@@ -1092,7 +1092,7 @@ void Dialog::GrabFocusToFirstControl()
 
     // find focus control, even if the dialog has focus
     if ( HasFocus() )
-        pFocusControl = NULL;
+        pFocusControl = nullptr;
     else
     {
         // prefer a child window which had focus before
@@ -1174,7 +1174,7 @@ bool Dialog::set_property(const OString &rKey, const OString &rValue)
 }
 
 VclBuilderContainer::VclBuilderContainer()
-    : m_pUIBuilder(NULL)
+    : m_pUIBuilder(nullptr)
 {
 }
 
diff --git a/vcl/source/window/dlgctrl.cxx b/vcl/source/window/dlgctrl.cxx
index 097f3ef95e8e..11f3c3c96fbd 100644
--- a/vcl/source/window/dlgctrl.cxx
+++ b/vcl/source/window/dlgctrl.cxx
@@ -70,8 +70,8 @@ static vcl::Window* ImplGetTopParentOfTabHierarchy( vcl::Window* pParent )
 
 static vcl::Window* ImplGetSubChildWindow( vcl::Window* pParent, sal_uInt16 n, sal_uInt16& nIndex )
 {
-    vcl::Window*     pTabPage = NULL;
-    vcl::Window*     pFoundWindow = NULL;
+    vcl::Window*     pTabPage = nullptr;
+    vcl::Window*     pFoundWindow = nullptr;
 
     vcl::Window*     pWindow = firstLogicalChildOfParent(pParent);
     vcl::Window*     pNextWindow = pWindow;
@@ -86,7 +86,7 @@ static vcl::Window* ImplGetSubChildWindow( vcl::Window* pParent, sal_uInt16 n, s
             if ( pTabPage )
             {
                 pFoundWindow = ImplGetSubChildWindow( pTabPage, n, nIndex );
-                pTabPage = NULL;
+                pTabPage = nullptr;
             }
             else
             {
@@ -189,7 +189,7 @@ vcl::Window* Window::ImplGetDlgWindow( sal_uInt16 nIndex, GetDlgWindowType nType
     DBG_ASSERT( (nIndex >= nFormStart) && (nIndex <= nFormEnd),
                 "Window::ImplGetDlgWindow() - nIndex not in Form" );
 
-    vcl::Window* pWindow = NULL;
+    vcl::Window* pWindow = nullptr;
     sal_uInt16  i;
     sal_uInt16  nTemp;
     sal_uInt16  nStartIndex;
@@ -275,7 +275,7 @@ vcl::Window* Window::ImplGetDlgWindow( sal_uInt16 nIndex, GetDlgWindowType nType
                 }
 
                 if ( !(pWindow->GetStyle() & WB_TABSTOP) )
-                    pWindow = NULL;
+                    pWindow = nullptr;
             }
         }
     }
@@ -292,8 +292,8 @@ vcl::Window* ImplFindDlgCtrlWindow( vcl::Window* pParent, vcl::Window* pWindow,
                                sal_uInt16& rFormStart, sal_uInt16& rFormEnd )
 {
     vcl::Window* pSWindow;
-    vcl::Window* pSecondWindow = NULL;
-    vcl::Window* pTempWindow = NULL;
+    vcl::Window* pSecondWindow = nullptr;
+    vcl::Window* pTempWindow = nullptr;
     sal_uInt16  i;
     sal_uInt16  nSecond_i = 0;
     sal_uInt16  nFormStart = 0;
@@ -303,7 +303,7 @@ vcl::Window* ImplFindDlgCtrlWindow( vcl::Window* pParent, vcl::Window* pWindow,
     // find focus window in the child list
     vcl::Window* pFirstChildWindow = pSWindow = ImplGetChildWindow( pParent, 0, i, false );
 
-    if( pWindow == NULL )
+    if( pWindow == nullptr )
         pWindow = pSWindow;
 
     while ( pSWindow )
@@ -325,14 +325,14 @@ vcl::Window* ImplFindDlgCtrlWindow( vcl::Window* pParent, vcl::Window* pWindow,
 
         pSWindow = ImplGetNextWindow( pParent, i, i, false );
         if ( !i )
-            pSWindow = NULL;
+            pSWindow = nullptr;
     }
 
     if ( !pSWindow )
     {
         // Window not found; we cannot handle it
         if ( !pSecondWindow )
-            return NULL;
+            return nullptr;
         else
         {
             pSWindow = pSecondWindow;
@@ -445,7 +445,7 @@ vcl::Window* ImplFindAccelWindow( vcl::Window* pParent, sal_uInt16& rIndex, sal_
             sal_uInt16  nChildFormEnd;
 
             // get form start and end
-            ::ImplFindDlgCtrlWindow( pWindow, NULL,
+            ::ImplFindDlgCtrlWindow( pWindow, nullptr,
                                      nChildIndex, nChildFormStart, nChildFormEnd );
             vcl::Window* pAccelWin = ImplFindAccelWindow( pWindow, nChildIndex, cCharCode,
                                                      nChildFormStart, nChildFormEnd,
@@ -467,7 +467,7 @@ vcl::Window* ImplFindAccelWindow( vcl::Window* pParent, sal_uInt16& rIndex, sal_
             pWindow = ImplGetChildWindow( pParent, nFormStart, i, bCheckEnable );
     }
 
-    return NULL;
+    return nullptr;
 }
 
 namespace vcl {
@@ -619,7 +619,7 @@ bool Window::ImplDlgCtrl( const KeyEvent& rKEvt, bool bKeyInput )
     }
     while ( pTempWindow );
 
-    pButtonWindow = NULL;
+    pButtonWindow = nullptr;
 
     if ( nKeyCode == KEY_RETURN )
     {
@@ -634,7 +634,7 @@ bool Window::ImplDlgCtrl( const KeyEvent& rKEvt, bool bKeyInput )
 
             pButtonWindow = ImplGetNextWindow( this, iButton, iButton, true );
             if ( (iButton <= iButtonStart) || (iButton > nFormEnd) )
-                pButtonWindow = NULL;
+                pButtonWindow = nullptr;
         }
 
         if ( bKeyInput && !pButtonWindow && (nDlgCtrlFlags & DialogControlFlags::Return) )
@@ -679,7 +679,7 @@ bool Window::ImplDlgCtrl( const KeyEvent& rKEvt, bool bKeyInput )
                     pTempWindow = ImplGetDlgWindow( i, nType, nFormStart, nFormEnd, &nNewIndex );
                 }
                 if ( (i <= iStart) || (i > nFormEnd) )
-                    pTempWindow = NULL;
+                    pTempWindow = nullptr;
             }
             // if this is the same window, simulate a Get/LoseFocus,
             // in case AROUND is being processed
@@ -709,7 +709,7 @@ bool Window::ImplDlgCtrl( const KeyEvent& rKEvt, bool bKeyInput )
 
             pButtonWindow = ImplGetNextWindow( this, iButton, iButton, true );
             if ( (iButton <= iButtonStart) || (iButton > nFormEnd) )
-                pButtonWindow = NULL;
+                pButtonWindow = nullptr;
         }
 
         if ( bKeyInput && mpWindowImpl->mpDlgCtrlDownWindow )
@@ -717,7 +717,7 @@ bool Window::ImplDlgCtrl( const KeyEvent& rKEvt, bool bKeyInput )
             if ( mpWindowImpl->mpDlgCtrlDownWindow.get() != pButtonWindow )
             {
                 static_cast<PushButton*>(mpWindowImpl->mpDlgCtrlDownWindow.get())->SetPressed( false );
-                mpWindowImpl->mpDlgCtrlDownWindow = NULL;
+                mpWindowImpl->mpDlgCtrlDownWindow = nullptr;
                 return true;
             }
         }
@@ -738,10 +738,10 @@ bool Window::ImplDlgCtrl( const KeyEvent& rKEvt, bool bKeyInput )
                 if ( aKeyCode.IsMod1() )
                 {
                     // search group
-                    vcl::Window* pFormularFirstWindow = NULL;
-                    vcl::Window* pLastFormularFirstWindow = NULL;
+                    vcl::Window* pFormularFirstWindow = nullptr;
+                    vcl::Window* pLastFormularFirstWindow = nullptr;
                     pTempWindow = ImplGetChildWindow( this, 0, iTemp, false );
-                    vcl::Window* pPrevFirstFormularFirstWindow = NULL;
+                    vcl::Window* pPrevFirstFormularFirstWindow = nullptr;
                     vcl::Window* pFirstFormularFirstWindow = pTempWindow;
                     while ( pTempWindow )
                     {
@@ -765,7 +765,7 @@ bool Window::ImplDlgCtrl( const KeyEvent& rKEvt, bool bKeyInput )
 
                         pTempWindow = ImplGetNextWindow( this, iTemp, iTemp, false );
                         if ( !iTemp )
-                            pTempWindow = NULL;
+                            pTempWindow = nullptr;
                     }
 
                     if ( bFormular )
@@ -929,7 +929,7 @@ bool Window::ImplDlgCtrl( const KeyEvent& rKEvt, bool bKeyInput )
             if ( mpWindowImpl->mpDlgCtrlDownWindow && (mpWindowImpl->mpDlgCtrlDownWindow.get() != pButtonWindow) )
             {
                 static_cast<PushButton*>(mpWindowImpl->mpDlgCtrlDownWindow.get())->SetPressed( false );
-                mpWindowImpl->mpDlgCtrlDownWindow = NULL;
+                mpWindowImpl->mpDlgCtrlDownWindow = nullptr;
             }
 
             static_cast<PushButton*>(pButtonWindow)->SetPressed( true );
@@ -937,7 +937,7 @@ bool Window::ImplDlgCtrl( const KeyEvent& rKEvt, bool bKeyInput )
         }
         else if ( mpWindowImpl->mpDlgCtrlDownWindow.get() == pButtonWindow )
         {
-            mpWindowImpl->mpDlgCtrlDownWindow = NULL;
+            mpWindowImpl->mpDlgCtrlDownWindow = nullptr;
             static_cast<PushButton*>(pButtonWindow)->SetPressed( false );
             static_cast<PushButton*>(pButtonWindow)->Click();
         }
@@ -1000,8 +1000,8 @@ if ( !pDlgCtrlParent || (GetStyle() & WB_NODIALOGCONTROL) || ((pDlgCtrlParent->G
 static void ImplDlgCtrlUpdateDefButton( vcl::Window* pParent, vcl::Window* pFocusWindow,
                                         bool bGetFocus )
 {
-    PushButton* pOldDefButton   = NULL;
-    PushButton* pNewDefButton   = NULL;
+    PushButton* pOldDefButton   = nullptr;
+    PushButton* pNewDefButton   = nullptr;
     vcl::Window*     pSWindow;
     sal_uInt16      i;
     sal_uInt16      nFormStart;
@@ -1031,7 +1031,7 @@ static void ImplDlgCtrlUpdateDefButton( vcl::Window* pParent, vcl::Window* pFocu
 
         pSWindow = ImplGetNextWindow( pParent, i, i, false );
         if ( !i || (i > nFormEnd) )
-            pSWindow = NULL;
+            pSWindow = nullptr;
     }
 
     if ( !bGetFocus )
@@ -1039,10 +1039,10 @@ static void ImplDlgCtrlUpdateDefButton( vcl::Window* pParent, vcl::Window* pFocu
         sal_uInt16 nDummy;
         vcl::Window* pNewFocusWindow = Application::GetFocusWindow();
         if ( !pNewFocusWindow || !pParent->ImplIsWindowOrChild( pNewFocusWindow ) )
-            pNewDefButton = NULL;
+            pNewDefButton = nullptr;
         else if ( !::ImplFindDlgCtrlWindow( pParent, pNewFocusWindow, i, nDummy, nDummy ) ||
                   (i < nFormStart) || (i > nFormEnd) )
-            pNewDefButton = NULL;
+            pNewDefButton = nullptr;
     }
 
     if ( pOldDefButton != pNewDefButton )
@@ -1059,7 +1059,7 @@ void Window::ImplDlgCtrlFocusChanged( vcl::Window* pWindow, bool bGetFocus )
     if ( mpWindowImpl->mpDlgCtrlDownWindow && !bGetFocus )
     {
         static_cast<PushButton*>(mpWindowImpl->mpDlgCtrlDownWindow.get())->SetPressed( false );
-        mpWindowImpl->mpDlgCtrlDownWindow = NULL;
+        mpWindowImpl->mpDlgCtrlDownWindow = nullptr;
     }
 
     ImplDlgCtrlUpdateDefButton( this, pWindow, bGetFocus );
@@ -1077,12 +1077,12 @@ vcl::Window* Window::ImplFindDlgCtrlWindow( vcl::Window* pWindow )
 
 vcl::Window* Window::GetParentLabelFor( const vcl::Window* ) const
 {
-    return NULL;
+    return nullptr;
 }
 
 vcl::Window* Window::GetParentLabeledBy( const vcl::Window* ) const
 {
-    return NULL;
+    return nullptr;
 }
 
 KeyEvent Window::GetActivationKey() const
diff --git a/vcl/source/window/dndevdis.cxx b/vcl/source/window/dndevdis.cxx
index 33dfbc44366c..a436bdefa002 100644
--- a/vcl/source/window/dndevdis.cxx
+++ b/vcl/source/window/dndevdis.cxx
@@ -35,14 +35,14 @@ using namespace ::com::sun::star::datatransfer::dnd;
 // DNDEventDispatcher::DNDEventDispatcher
 DNDEventDispatcher::DNDEventDispatcher( vcl::Window * pTopWindow ):
     m_pTopWindow( pTopWindow ),
-    m_pCurrentWindow( NULL )
+    m_pCurrentWindow( nullptr )
 {
 }
 
 // DNDEventDispatcher::~DNDEventDispatcher
 DNDEventDispatcher::~DNDEventDispatcher()
 {
-    designate_currentwindow(NULL);
+    designate_currentwindow(nullptr);
 }
 
 vcl::Window* DNDEventDispatcher::findTopLevelWindow(Point location)
@@ -55,7 +55,7 @@ vcl::Window* DNDEventDispatcher::findTopLevelWindow(Point location)
         m_pTopWindow->ImplMirrorFramePos( location );
     vcl::Window * pChildWindow = m_pTopWindow->ImplFindWindow( location );
 
-    if( NULL == pChildWindow )
+    if( nullptr == pChildWindow )
         pChildWindow = m_pTopWindow;
 
     while( pChildWindow->ImplGetClientWindow() )
@@ -74,7 +74,7 @@ IMPL_LINK_TYPED(DNDEventDispatcher, WindowEventListener, VclWindowEvent&, rEvent
 {
     if (rEvent.GetId() == VCLEVENT_OBJECT_DYING)
     {
-        designate_currentwindow(NULL);
+        designate_currentwindow(nullptr);
     }
 }
 
@@ -120,7 +120,7 @@ void SAL_CALL DNDEventDispatcher::drop( const DropTargetDropEvent& dtde )
     }
 
     // this is a drop -> no further drag overs
-    designate_currentwindow(NULL);
+    designate_currentwindow(nullptr);
     m_aDataFlavorList.realloc( 0 );
 }
 
@@ -160,7 +160,7 @@ void SAL_CALL DNDEventDispatcher::dragExit( const DropTargetEvent& /*dte*/ )
     fireDragExitEvent( m_pCurrentWindow );
 
     // reset member values
-    designate_currentwindow(NULL);
+    designate_currentwindow(nullptr);
     m_aDataFlavorList.realloc( 0 );
 }
 
diff --git a/vcl/source/window/dockingarea.cxx b/vcl/source/window/dockingarea.cxx
index 41330fb1326e..6ea846de11f3 100644
--- a/vcl/source/window/dockingarea.cxx
+++ b/vcl/source/window/dockingarea.cxx
@@ -47,7 +47,7 @@ DockingAreaWindow::ImplData::~ImplData()
 DockingAreaWindow::DockingAreaWindow( vcl::Window* pParent ) :
     Window( WINDOW_DOCKINGAREA )
 {
-    ImplInit( pParent, WB_CLIPCHILDREN|WB_3DLOOK, NULL );
+    ImplInit( pParent, WB_CLIPCHILDREN|WB_3DLOOK, nullptr );
 
     mpImplData = new ImplData;
 }
diff --git a/vcl/source/window/dockmgr.cxx b/vcl/source/window/dockmgr.cxx
index 05a08f599ca7..b3fc00522b08 100644
--- a/vcl/source/window/dockmgr.cxx
+++ b/vcl/source/window/dockmgr.cxx
@@ -75,7 +75,7 @@ ImplDockFloatWin2::ImplDockFloatWin2( vcl::Window* pParent, WinBits nWinBits,
         mpDockWin( pDockingWin ),
         mnLastTicks( tools::Time::GetSystemTicks() ),
         mbInMove( false ),
-        mnLastUserEvent( 0 )
+        mnLastUserEvent( nullptr )
 {
     // copy state of DockingWindow
     if ( pDockingWin )
@@ -154,7 +154,7 @@ IMPL_LINK_NOARG_TYPED(ImplDockFloatWin2, EndDockTimerHdl, Idle *, void)
 IMPL_LINK_NOARG_TYPED(ImplDockFloatWin2, DockingHdl, void*, void)
 {
     // called during move of a floating window
-    mnLastUserEvent = 0;
+    mnLastUserEvent = nullptr;
 
     vcl::Window *pDockingArea = mpDockWin->GetWindow()->GetParent();
     PointerState aState = pDockingArea->GetPointerState();
@@ -242,7 +242,7 @@ void ImplDockFloatWin2::Move()
      *  last Move message.
      */
     if( ! mnLastUserEvent )
-        mnLastUserEvent = Application::PostUserEvent( LINK( this, ImplDockFloatWin2, DockingHdl ), NULL, true );
+        mnLastUserEvent = Application::PostUserEvent( LINK( this, ImplDockFloatWin2, DockingHdl ), nullptr, true );
 }
 
 void ImplDockFloatWin2::Resize()
@@ -314,7 +314,7 @@ ImplDockingWindowWrapper* DockingManager::GetDockingWindowWrapper( const vcl::Wi
         else
             ++p;
     }
-    return NULL;
+    return nullptr;
 }
 
 bool DockingManager::IsDockable( const vcl::Window *pWindow )
@@ -325,7 +325,7 @@ bool DockingManager::IsDockable( const vcl::Window *pWindow )
     if( pWindow->HasDockingHandler() )
         return true;
     */
-    return (pWrapper != NULL);
+    return (pWrapper != nullptr);
 }
 
 bool DockingManager::IsFloating( const vcl::Window *pWindow )
@@ -521,7 +521,7 @@ ImplPopupFloatWin::~ImplPopupFloatWin()
 
 void ImplPopupFloatWin::dispose()
 {
-    mpDockingWin = NULL;
+    mpDockingWin = nullptr;
     FloatingWindow::dispose();
 }
 
@@ -794,8 +794,8 @@ void ImplPopupFloatWin::Tracking( const TrackingEvent& rTEvt )
 
 ImplDockingWindowWrapper::ImplDockingWindowWrapper( const vcl::Window *pWindow )
     : mpDockingWindow(const_cast<vcl::Window*>(pWindow))
-    , mpFloatWin(NULL)
-    , mpOldBorderWin(NULL)
+    , mpFloatWin(nullptr)
+    , mpOldBorderWin(nullptr)
     , mpParent(pWindow->GetParent())
     , maMaxOutSize( SHRT_MAX, SHRT_MAX )
     , mnTrackX(0)
@@ -1109,7 +1109,7 @@ void ImplDockingWindowWrapper::StartPopupMode( ToolBox *pParentToolBox, FloatWin
     vcl::Window* pRealParent = GetWindow()->GetWindow( GetWindowType::Parent );
     mpOldBorderWin = GetWindow()->GetWindow( GetWindowType::Border );
     if( mpOldBorderWin.get() == GetWindow() )
-        mpOldBorderWin = NULL;  // no border window found
+        mpOldBorderWin = nullptr;  // no border window found
 
     // the new parent for popup mode
     VclPtrInstance<ImplPopupFloatWin> pWin( mpParent, this, bool(nFlags & FloatWinPopupFlags::AllowTearOff) );
@@ -1119,7 +1119,7 @@ void ImplDockingWindowWrapper::StartPopupMode( ToolBox *pParentToolBox, FloatWin
 
     pWin->SetOutputSizePixel( GetWindow()->GetSizePixel() );
 
-    GetWindow()->mpWindowImpl->mpBorderWindow  = NULL;
+    GetWindow()->mpWindowImpl->mpBorderWindow  = nullptr;
     GetWindow()->mpWindowImpl->mnLeftBorder    = 0;
     GetWindow()->mpWindowImpl->mnTopBorder     = 0;
     GetWindow()->mpWindowImpl->mnRightBorder   = 0;
@@ -1168,7 +1168,7 @@ IMPL_LINK_NOARG_TYPED(ImplDockingWindowWrapper, PopupModeEnd, FloatingWindow*, v
 
     // before deleting change parent back, so we can delete the floating window alone
     vcl::Window* pRealParent = GetWindow()->GetWindow( GetWindowType::Parent );
-    GetWindow()->mpWindowImpl->mpBorderWindow = NULL;
+    GetWindow()->mpWindowImpl->mpBorderWindow = nullptr;
     if ( mpOldBorderWin )
     {
         GetWindow()->SetParent( mpOldBorderWin );
@@ -1216,7 +1216,7 @@ void ImplDockingWindowWrapper::SetFloatingMode( bool bFloatMode )
                 vcl::Window* pRealParent = GetWindow()->GetWindow( GetWindowType::Parent );
                 mpOldBorderWin = GetWindow()->GetWindow( GetWindowType::Border );
                 if( mpOldBorderWin == mpDockingWindow )
-                    mpOldBorderWin = NULL;  // no border window found
+                    mpOldBorderWin = nullptr;  // no border window found
 
                 ImplDockFloatWin2* pWin =
                     VclPtr<ImplDockFloatWin2>::Create(
@@ -1228,7 +1228,7 @@ void ImplDockingWindowWrapper::SetFloatingMode( bool bFloatMode )
                                           : mnFloatBits,
                                          this );
 
-                GetWindow()->mpWindowImpl->mpBorderWindow  = NULL;
+                GetWindow()->mpWindowImpl->mpBorderWindow  = nullptr;
                 GetWindow()->mpWindowImpl->mnLeftBorder    = 0;
                 GetWindow()->mpWindowImpl->mnTopBorder     = 0;
                 GetWindow()->mpWindowImpl->mnRightBorder   = 0;
@@ -1281,7 +1281,7 @@ void ImplDockingWindowWrapper::SetFloatingMode( bool bFloatMode )
                 maMaxOutSize    = mpFloatWin->GetMaxOutputSizePixel();
 
                 vcl::Window* pRealParent = GetWindow()->GetWindow( GetWindowType::Parent ); //mpWindowImpl->mpRealParent;
-                GetWindow()->mpWindowImpl->mpBorderWindow = NULL;
+                GetWindow()->mpWindowImpl->mpBorderWindow = nullptr;
                 if ( mpOldBorderWin )
                 {
                     GetWindow()->SetParent( mpOldBorderWin );
diff --git a/vcl/source/window/dockwin.cxx b/vcl/source/window/dockwin.cxx
index 083fd0e9a4bf..2f0fc5b57d9f 100644
--- a/vcl/source/window/dockwin.cxx
+++ b/vcl/source/window/dockwin.cxx
@@ -48,7 +48,7 @@ public:
 
 DockingWindow::ImplData::ImplData()
 {
-    mpParent = NULL;
+    mpParent = nullptr;
     maMaxOutSize = Size( SHRT_MAX, SHRT_MAX );
 }
 
@@ -91,7 +91,7 @@ ImplDockFloatWin::ImplDockFloatWin( vcl::Window* pParent, WinBits nWinBits,
         mpDockWin( pDockingWin ),
         mnLastTicks( tools::Time::GetSystemTicks() ),
         mbInMove( false ),
-        mnLastUserEvent( 0 )
+        mnLastUserEvent( nullptr )
 {
     // copy settings of DockingWindow
     if ( pDockingWin )
@@ -157,7 +157,7 @@ IMPL_LINK_NOARG_TYPED(ImplDockFloatWin, DockingHdl, void*, void)
 {
     PointerState aState = mpDockWin->GetParent()->GetPointerState();
 
-    mnLastUserEvent = 0;
+    mnLastUserEvent = nullptr;
     if( mpDockWin->IsDockable()                             &&
         (tools::Time::GetSystemTicks() - mnLastTicks > 500)        &&
         ( aState.mnState & ( MOUSE_LEFT | MOUSE_MIDDLE | MOUSE_RIGHT ) ) &&
@@ -208,7 +208,7 @@ void ImplDockFloatWin::Move()
      *  last Move message.
      */
     if( ! mnLastUserEvent )
-        mnLastUserEvent = Application::PostUserEvent( LINK( this, ImplDockFloatWin, DockingHdl ), NULL, true );
+        mnLastUserEvent = Application::PostUserEvent( LINK( this, ImplDockFloatWin, DockingHdl ), nullptr, true );
 }
 
 void ImplDockFloatWin::Resize()
@@ -305,8 +305,8 @@ bool DockingWindow::ImplStartDocking( const Point& rPos )
 void DockingWindow::ImplInitDockingWindowData()
 {
     mpWindowImpl->mbDockWin = true;
-    mpFloatWin     = NULL;
-    mpOldBorderWin = NULL;
+    mpFloatWin     = nullptr;
+    mpOldBorderWin = nullptr;
     mpImplData     = new ImplData;
     mnTrackX       = 0;
     mnTrackY       = 0;
@@ -333,7 +333,7 @@ void DockingWindow::ImplInitDockingWindowData()
     mbIsDefferedInit = false;
     mbIsCalculatingInitialLayoutSize = false;
     mbInitialLayoutDone = false;
-    mpDialogParent = NULL;
+    mpDialogParent = nullptr;
 
     //To-Do, reuse maResizeTimer
     maLayoutIdle.SetPriority(SchedulerPriority::RESIZE);
@@ -352,7 +352,7 @@ void DockingWindow::ImplInit( vcl::Window* pParent, WinBits nStyle )
     if ( nStyle & WB_DOCKBORDER )
         nStyle |= WB_BORDER;
 
-    Window::ImplInit( pParent, nStyle, NULL );
+    Window::ImplInit( pParent, nStyle, nullptr );
 
     ImplInitSettings();
 }
@@ -444,7 +444,7 @@ DockingWindow::DockingWindow( vcl::Window* pParent, const ResId& rResId ) :
 void DockingWindow::doDeferredInit(WinBits nBits)
 {
     vcl::Window *pParent = mpDialogParent;
-    mpDialogParent = NULL;
+    mpDialogParent = nullptr;
     ImplInit(pParent, nBits);
     mbIsDefferedInit = false;
 }
@@ -479,7 +479,7 @@ void DockingWindow::dispose()
         SetFloatingMode(false);
     }
     delete mpImplData;
-    mpImplData = NULL;
+    mpImplData = nullptr;
     mpFloatWin.clear();
     mpOldBorderWin.clear();
     mpDialogParent.clear();
@@ -805,7 +805,7 @@ void DockingWindow::SetFloatingMode( bool bFloatMode )
                                          mnFloatBits & ( WB_MOVEABLE | WB_SIZEABLE | WB_CLOSEABLE ) ?  mnFloatBits | WB_SYSTEMWINDOW : mnFloatBits,
                                          this );
                 mpFloatWin      = pWin;
-                mpWindowImpl->mpBorderWindow  = NULL;
+                mpWindowImpl->mpBorderWindow  = nullptr;
                 mpWindowImpl->mnLeftBorder    = 0;
                 mpWindowImpl->mnTopBorder     = 0;
                 mpWindowImpl->mnRightBorder   = 0;
@@ -866,7 +866,7 @@ void DockingWindow::SetFloatingMode( bool bFloatMode )
                 mpImplData->maMaxOutSize = mpFloatWin->GetMaxOutputSizePixel();
 
                 vcl::Window* pRealParent = mpWindowImpl->mpRealParent;
-                mpWindowImpl->mpBorderWindow = NULL;
+                mpWindowImpl->mpBorderWindow = nullptr;
                 if ( mpOldBorderWin )
                 {
                     SetParent( mpOldBorderWin );
diff --git a/vcl/source/window/event.cxx b/vcl/source/window/event.cxx
index 548e8704054c..c31aa63e1fe4 100644
--- a/vcl/source/window/event.cxx
+++ b/vcl/source/window/event.cxx
@@ -316,7 +316,7 @@ ImplSVEvent * Window::PostUserEvent( const Link<void*,void>& rLink, void* pCalle
     {
         ImplRemoveDel( &(pSVEvent->maDelData) );
         delete pSVEvent;
-        pSVEvent = 0;
+        pSVEvent = nullptr;
     }
     return pSVEvent;
 }
@@ -331,7 +331,7 @@ void Window::RemoveUserEvent( ImplSVEvent * nUserEvent )
     if ( nUserEvent->mpWindow )
     {
         nUserEvent->mpWindow->ImplRemoveDel( &(nUserEvent->maDelData) );
-        nUserEvent->mpWindow = NULL;
+        nUserEvent->mpWindow = nullptr;
     }
 
     nUserEvent->mbCall = false;
@@ -507,7 +507,7 @@ void Window::ImplCallMove()
     if( mpWindowImpl->mbFrame )
     {
         // update frame position
-        SalFrame *pParentFrame = NULL;
+        SalFrame *pParentFrame = nullptr;
         vcl::Window *pParent = ImplGetParent();
         while( pParent )
         {
@@ -581,7 +581,7 @@ void Window::ImplCallFocusChangeActivate( vcl::Window* pNewOverlapWindow,
                     pLastRealWindow->Activate();
                 }
             }
-            pSVData->maWinData.mpLastDeacWin = NULL;
+            pSVData->maWinData.mpLastDeacWin = nullptr;
         }
     }
 
@@ -623,8 +623,8 @@ void Window::ImplCallFocusChangeActivate( vcl::Window* pNewOverlapWindow,
 
 NotifyEvent::NotifyEvent()
 {
-    mpWindow    = NULL;
-    mpData      = NULL;
+    mpWindow    = nullptr;
+    mpData      = nullptr;
     mnEventType = MouseNotifyEvent::NONE;
     mnRetValue  = 0;
 }
diff --git a/vcl/source/window/floatwin.cxx b/vcl/source/window/floatwin.cxx
index c470f754d004..b5c038ccdb53 100644
--- a/vcl/source/window/floatwin.cxx
+++ b/vcl/source/window/floatwin.cxx
@@ -45,7 +45,7 @@ public:
 
 FloatingWindow::ImplData::ImplData()
 {
-    mpBox = NULL;
+    mpBox = nullptr;
 }
 
 FloatingWindow::ImplData::~ImplData()
@@ -77,7 +77,7 @@ void FloatingWindow::ImplInit( vcl::Window* pParent, WinBits nStyle )
     {
         mpWindowImpl->mbOverlapWin = true;
         nStyle |= WB_DIALOGCONTROL;
-        SystemWindow::ImplInit(pParent, nStyle, NULL);
+        SystemWindow::ImplInit(pParent, nStyle, nullptr);
     }
     else
     {
@@ -92,7 +92,7 @@ void FloatingWindow::ImplInit( vcl::Window* pParent, WinBits nStyle )
             // nFloatWinStyle |= WB_CLOSEABLE;
             mpWindowImpl->mbFrame = true;
             mpWindowImpl->mbOverlapWin = true;
-            SystemWindow::ImplInit(pParent, nFloatWinStyle & ~WB_BORDER, NULL);
+            SystemWindow::ImplInit(pParent, nFloatWinStyle & ~WB_BORDER, nullptr);
         }
         else
         {
@@ -110,7 +110,7 @@ void FloatingWindow::ImplInit( vcl::Window* pParent, WinBits nStyle )
                 nStyle |= WB_CLOSEABLE; // make undecorated floaters closeable
             }
             pBorderWin  = VclPtr<ImplBorderWindow>::Create(pParent, nStyle, nBorderStyle);
-            SystemWindow::ImplInit(pBorderWin, nStyle & ~WB_BORDER, NULL);
+            SystemWindow::ImplInit(pBorderWin, nStyle & ~WB_BORDER, nullptr);
             pBorderWin->mpWindowImpl->mpClientWindow = this;
             pBorderWin->GetBorder(mpWindowImpl->mnLeftBorder, mpWindowImpl->mnTopBorder,
                                   mpWindowImpl->mnRightBorder, mpWindowImpl->mnBottomBorder);
@@ -121,9 +121,9 @@ void FloatingWindow::ImplInit( vcl::Window* pParent, WinBits nStyle )
     }
     SetActivateMode( ActivateModeFlags::NONE );
 
-    mpNextFloat             = NULL;
-    mpFirstPopupModeWin     = NULL;
-    mnPostId                = 0;
+    mpNextFloat             = nullptr;
+    mpFirstPopupModeWin     = nullptr;
+    mnPostId                = nullptr;
     mnTitle                 = (nStyle & (WB_MOVEABLE | WB_POPUP)) ? FloatWinTitleType::Normal : FloatWinTitleType::NONE;
     mnOldTitle              = mnTitle;
     mnPopupModeFlags        = FloatWinPopupFlags::NONE;
@@ -158,10 +158,10 @@ FloatingWindow::FloatingWindow(vcl::Window* pParent, WinBits nStyle) :
 
 FloatingWindow::FloatingWindow(vcl::Window* pParent, const OString& rID, const OUString& rUIXMLDescription, const css::uno::Reference<css::frame::XFrame> &rFrame)
     : SystemWindow(WINDOW_FLOATINGWINDOW)
-    , mpNextFloat(0)
-    , mpFirstPopupModeWin(0)
-    , mpImplData(0)
-    , mnPostId(0)
+    , mpNextFloat(nullptr)
+    , mpFirstPopupModeWin(nullptr)
+    , mpImplData(nullptr)
+    , mnPostId(nullptr)
     , mnPopupModeFlags(FloatWinPopupFlags::NONE)
     , mnTitle(FloatWinTitleType::Unknown)
     , mnOldTitle(FloatWinTitleType::Unknown)
@@ -181,7 +181,7 @@ FloatingWindow::FloatingWindow(vcl::Window* pParent, const OString& rID, const O
 void FloatingWindow::doDeferredInit(WinBits nBits)
 {
     vcl::Window *pParent = mpDialogParent;
-    mpDialogParent = NULL;
+    mpDialogParent = nullptr;
     ImplInit(pParent, nBits);
     mbIsDefferedInit = false;
 }
@@ -223,11 +223,11 @@ void FloatingWindow::dispose()
 
         if ( mnPostId )
             Application::RemoveUserEvent( mnPostId );
-        mnPostId = 0;
+        mnPostId = nullptr;
     }
 
     delete mpImplData;
-    mpImplData = NULL;
+    mpImplData = nullptr;
 
     mpNextFloat.clear();
     mpFirstPopupModeWin.clear();
@@ -503,7 +503,7 @@ FloatingWindow* FloatingWindow::ImplFloatHitTest( vcl::Window* pReference, const
     while ( pWin );
 
     rHitTest = HITTEST_OUTSIDE;
-    return NULL;
+    return nullptr;
 }
 
 FloatingWindow* FloatingWindow::ImplFindLastLevelFloat()
@@ -542,7 +542,7 @@ bool FloatingWindow::ImplIsFloatPopupModeWindow( const vcl::Window* pWindow )
 IMPL_LINK_NOARG_TYPED(FloatingWindow, ImplEndPopupModeHdl, void*, void)
 {
     VclPtr<FloatingWindow> pThis(this);
-    mnPostId            = 0;
+    mnPostId            = nullptr;
     mnPopupModeFlags    = FloatWinPopupFlags::NONE;
     mbPopupMode         = false;
     PopupModeEnd();
@@ -606,7 +606,7 @@ void FloatingWindow::ImplCallPopupModeEnd()
 
     // call Handler asynchronously.
     if ( mpImplData && !mnPostId )
-        mnPostId = Application::PostUserEvent( LINK( this, FloatingWindow, ImplEndPopupModeHdl ), NULL, true );
+        mnPostId = Application::PostUserEvent( LINK( this, FloatingWindow, ImplEndPopupModeHdl ), nullptr, true );
 }
 
 void FloatingWindow::PopupModeEnd()
@@ -771,7 +771,7 @@ void FloatingWindow::ImplEndPopupMode( FloatWinPopupEndFlags nFlags, sal_uLong n
 
     // delete window from the list
     pSVData->maWinData.mpFirstFloat = mpNextFloat;
-    mpNextFloat = NULL;
+    mpNextFloat = nullptr;
 
     FloatWinPopupFlags nPopupModeFlags = mnPopupModeFlags;
 
@@ -806,7 +806,7 @@ void FloatingWindow::ImplEndPopupMode( FloatWinPopupEndFlags nFlags, sal_uLong n
     if ( mpImplData->mpBox )
     {
         mpImplData->mpBox->ImplFloatControl( false, this );
-        mpImplData->mpBox = NULL;
+        mpImplData->mpBox = nullptr;
     }
 
     // call PopupModeEnd-Handler depending on parameter
diff --git a/vcl/source/window/introwin.cxx b/vcl/source/window/introwin.cxx
index b7bd49bba6a9..50c871203e90 100644
--- a/vcl/source/window/introwin.cxx
+++ b/vcl/source/window/introwin.cxx
@@ -35,7 +35,7 @@ IntroWindow::IntroWindow( ) :
     WorkWindow( WINDOW_INTROWINDOW )
 {
     ImplInitIntroWindowData();
-    WorkWindow::ImplInit( 0, WB_INTROWIN );
+    WorkWindow::ImplInit( nullptr, WB_INTROWIN );
 }
 
 IntroWindow::~IntroWindow()
diff --git a/vcl/source/window/layout.cxx b/vcl/source/window/layout.cxx
index aa8f6518161a..62e9e4fd7682 100644
--- a/vcl/source/window/layout.cxx
+++ b/vcl/source/window/layout.cxx
@@ -20,7 +20,7 @@ VclContainer::VclContainer(vcl::Window *pParent, WinBits nStyle)
     : Window(WINDOW_CONTAINER)
     , m_bLayoutDirty(true)
 {
-    ImplInit(pParent, nStyle, NULL);
+    ImplInit(pParent, nStyle, nullptr);
     EnableChildTransparentMode();
     SetPaintTransparent(true);
     SetBackground();
@@ -757,7 +757,7 @@ struct GridEntry
     int x;
     int y;
     GridEntry()
-        : pChild(0)
+        : pChild(nullptr)
         , nSpanWidth(0)
         , nSpanHeight(0)
         , x(-1)
@@ -1370,7 +1370,7 @@ void VclFrame::setAllocation(const Size &rAllocation)
 IMPL_LINK_TYPED(VclFrame, WindowEventListener, VclWindowEvent&, rEvent, void)
 {
     if (rEvent.GetId() == VCLEVENT_OBJECT_DYING)
-        designate_label(NULL);
+        designate_label(nullptr);
 }
 
 void VclFrame::designate_label(vcl::Window *pWindow)
@@ -1391,7 +1391,7 @@ const vcl::Window *VclFrame::get_label_widget() const
     //The label widget is normally the first (of two) children
     const WindowImpl* pWindowImpl = ImplGetWindowImpl();
     if (pWindowImpl->mpFirstChild == pWindowImpl->mpLastChild) //no label exists
-        return NULL;
+        return nullptr;
     return pWindowImpl->mpFirstChild;
 }
 
@@ -1408,7 +1408,7 @@ const vcl::Window *VclFrame::get_child() const
     if (!m_pLabel)
         return pWindowImpl->mpLastChild;
     if (pWindowImpl->mpFirstChild == pWindowImpl->mpLastChild) //only label exists
-        return NULL;
+        return nullptr;
     return pWindowImpl->mpLastChild;
 }
 
@@ -1520,7 +1520,7 @@ Size VclExpander::calculateRequisition() const
     WindowImpl* pWindowImpl = ImplGetWindowImpl();
 
     const vcl::Window *pChild = get_child();
-    const vcl::Window *pLabel = pChild != pWindowImpl->mpLastChild ? pWindowImpl->mpLastChild.get() : NULL;
+    const vcl::Window *pLabel = pChild != pWindowImpl->mpLastChild ? pWindowImpl->mpLastChild.get() : nullptr;
 
     if (pChild && pChild->IsVisible() && m_pDisclosureButton->IsChecked())
         aRet = getLayoutRequisition(*pChild);
@@ -1557,7 +1557,7 @@ void VclExpander::setAllocation(const Size &rAllocation)
 
     //The label widget is the last (of two) children
     vcl::Window *pChild = get_child();
-    vcl::Window *pLabel = pChild != pWindowImpl->mpLastChild.get() ? pWindowImpl->mpLastChild.get() : NULL;
+    vcl::Window *pLabel = pChild != pWindowImpl->mpLastChild.get() ? pWindowImpl->mpLastChild.get() : nullptr;
 
     Size aButtonSize = getLayoutRequisition(*m_pDisclosureButton);
     Size aLabelSize;
@@ -1631,7 +1631,7 @@ IMPL_LINK_TYPED( VclExpander, ClickHdl, CheckBox&, rBtn, void )
     {
         pChild->Show(rBtn.IsChecked());
         queue_resize();
-        Dialog* pResizeDialog = m_bResizeTopLevel ? GetParentDialog() : NULL;
+        Dialog* pResizeDialog = m_bResizeTopLevel ? GetParentDialog() : nullptr;
         if (pResizeDialog)
             pResizeDialog->setOptimalLayoutSize();
     }
@@ -1999,12 +1999,12 @@ MessageDialog::MessageDialog(vcl::Window* pParent, WinBits nStyle)
     : Dialog(pParent, nStyle)
     , m_eButtonsType(VCL_BUTTONS_NONE)
     , m_eMessageType(VCL_MESSAGE_INFO)
-    , m_pOwnedContentArea(NULL)
-    , m_pOwnedActionArea(NULL)
-    , m_pGrid(NULL)
-    , m_pImage(NULL)
-    , m_pPrimaryMessage(NULL)
-    , m_pSecondaryMessage(NULL)
+    , m_pOwnedContentArea(nullptr)
+    , m_pOwnedActionArea(nullptr)
+    , m_pGrid(nullptr)
+    , m_pImage(nullptr)
+    , m_pPrimaryMessage(nullptr)
+    , m_pSecondaryMessage(nullptr)
 {
     SetType(WINDOW_MESSBOX);
 }
@@ -2017,10 +2017,10 @@ MessageDialog::MessageDialog(vcl::Window* pParent,
     : Dialog(pParent, nStyle)
     , m_eButtonsType(eButtonsType)
     , m_eMessageType(eMessageType)
-    , m_pGrid(NULL)
-    , m_pImage(NULL)
-    , m_pPrimaryMessage(NULL)
-    , m_pSecondaryMessage(NULL)
+    , m_pGrid(nullptr)
+    , m_pImage(nullptr)
+    , m_pPrimaryMessage(nullptr)
+    , m_pSecondaryMessage(nullptr)
     , m_sPrimaryString(rMessage)
 {
     SetType(WINDOW_MESSBOX);
@@ -2031,12 +2031,12 @@ MessageDialog::MessageDialog(vcl::Window* pParent, const OString& rID, const OUS
     : Dialog(pParent, OStringToOUString(rID, RTL_TEXTENCODING_UTF8), rUIXMLDescription, WINDOW_MESSBOX)
     , m_eButtonsType(VCL_BUTTONS_NONE)
     , m_eMessageType(VCL_MESSAGE_INFO)
-    , m_pOwnedContentArea(NULL)
-    , m_pOwnedActionArea(NULL)
-    , m_pGrid(NULL)
-    , m_pImage(NULL)
-    , m_pPrimaryMessage(NULL)
-    , m_pSecondaryMessage(NULL)
+    , m_pOwnedContentArea(nullptr)
+    , m_pOwnedActionArea(nullptr)
+    , m_pGrid(nullptr)
+    , m_pImage(nullptr)
+    , m_pPrimaryMessage(nullptr)
+    , m_pSecondaryMessage(nullptr)
 {
 }
 
@@ -2194,7 +2194,7 @@ short MessageDialog::Execute()
         m_pSecondaryMessage->SetText(m_sSecondaryString);
         m_pSecondaryMessage->Show(bHasSecondaryText);
 
-        MessageDialog::SetMessagesWidths(this, m_pPrimaryMessage, bHasSecondaryText ? m_pSecondaryMessage.get() : NULL);
+        MessageDialog::SetMessagesWidths(this, m_pPrimaryMessage, bHasSecondaryText ? m_pSecondaryMessage.get() : nullptr);
 
         VclButtonBox *pButtonBox = get_action_area();
         assert(pButtonBox);
@@ -2417,13 +2417,13 @@ bool isEnabledInLayout(const vcl::Window *pWindow)
 bool isLayoutEnabled(const vcl::Window *pWindow)
 {
     //Child is a container => we're layout enabled
-    const vcl::Window *pChild = pWindow ? pWindow->GetWindow(GetWindowType::FirstChild) : NULL;
+    const vcl::Window *pChild = pWindow ? pWindow->GetWindow(GetWindowType::FirstChild) : nullptr;
     return pChild && isContainerWindow(*pChild) && !pChild->GetWindow(GetWindowType::Next);
 }
 
 bool isInitialLayout(const vcl::Window *pWindow)
 {
-    Dialog *pParentDialog = pWindow ? pWindow->GetParentDialog() : NULL;
+    Dialog *pParentDialog = pWindow ? pWindow->GetParentDialog() : nullptr;
     return pParentDialog && pParentDialog->isCalculatingInitialLayoutSize();
 }
 
diff --git a/vcl/source/window/legacyaccessibility.cxx b/vcl/source/window/legacyaccessibility.cxx
index aa0cf67ad3f3..1cddcab06201 100644
--- a/vcl/source/window/legacyaccessibility.cxx
+++ b/vcl/source/window/legacyaccessibility.cxx
@@ -40,7 +40,7 @@ using namespace ::com::sun::star;
 
 static vcl::Window* ImplGetLabelFor( vcl::Window* pFrameWindow, WindowType nMyType, vcl::Window* pLabel, sal_Unicode nAccel )
 {
-    vcl::Window* pWindow = NULL;
+    vcl::Window* pWindow = nullptr;
 
     if( nMyType == WINDOW_FIXEDTEXT     ||
         nMyType == WINDOW_FIXEDLINE     ||
@@ -103,14 +103,14 @@ namespace vcl {
 
 Window* Window::getLegacyNonLayoutAccessibleRelationLabelFor() const
 {
-    Window* pWindow = NULL;
+    Window* pWindow = nullptr;
     Window* pFrameWindow = ImplGetFrameWindow();
 
     WinBits nFrameStyle = pFrameWindow->GetStyle();
     if( ! ( nFrameStyle & WB_DIALOGCONTROL )
         || ( nFrameStyle & WB_NODIALOGCONTROL )
         )
-        return NULL;
+        return nullptr;
 
     if ( mpWindowImpl->mpRealParent )
         pWindow = mpWindowImpl->mpRealParent->GetParentLabelFor( this );
@@ -128,7 +128,7 @@ Window* Window::getLegacyNonLayoutAccessibleRelationLabelFor() const
 
 static Window* ImplGetLabeledBy( Window* pFrameWindow, WindowType nMyType, Window* pLabeled )
 {
-    Window* pWindow = NULL;
+    Window* pWindow = nullptr;
     if ( (nMyType != WINDOW_GROUPBOX) && (nMyType != WINDOW_FIXEDLINE) )
     {
         // search for a control that labels this window
@@ -183,7 +183,7 @@ static Window* ImplGetLabeledBy( Window* pFrameWindow, WindowType nMyType, Windo
 
 Window* Window::getLegacyNonLayoutAccessibleRelationLabeledBy() const
 {
-    Window* pWindow = NULL;
+    Window* pWindow = nullptr;
     Window* pFrameWindow = ImplGetFrameWindow();
 
     if ( mpWindowImpl->mpRealParent )
@@ -196,7 +196,7 @@ Window* Window::getLegacyNonLayoutAccessibleRelationLabeledBy() const
 
     // #i62723#, #104191# checkboxes and radiobuttons are not supposed to have labels
     if( GetType() == WINDOW_CHECKBOX || GetType() == WINDOW_RADIOBUTTON )
-        return NULL;
+        return nullptr;
 
 //    if( ! ( GetType() == WINDOW_FIXEDTEXT     ||
 //            GetType() == WINDOW_FIXEDLINE     ||
@@ -213,7 +213,7 @@ Window* Window::getLegacyNonLayoutAccessibleRelationLabeledBy() const
 
 Window* Window::getLegacyNonLayoutAccessibleRelationMemberOf() const
 {
-    Window* pWindow = NULL;
+    Window* pWindow = nullptr;
     Window* pFrameWindow = GetParent();
     if ( !pFrameWindow )
     {
diff --git a/vcl/source/window/menu.cxx b/vcl/source/window/menu.cxx
index 6ca2bd38b9bd..49acb2e0c10c 100644
--- a/vcl/source/window/menu.cxx
+++ b/vcl/source/window/menu.cxx
@@ -114,13 +114,13 @@ static void ImplSetMenuItemData( MenuItemData* pData )
 }
 
 Menu::Menu()
-    : mpFirstDel(NULL),
+    : mpFirstDel(nullptr),
       pItemList(new MenuItemList),
-      pLogo(NULL),
-      pStartedFrom(NULL),
-      pWindow(NULL),
+      pLogo(nullptr),
+      pStartedFrom(nullptr),
+      pWindow(nullptr),
       nTitleHeight(0),
-      nEventId(0),
+      nEventId(nullptr),
       mnHighlightedItemPos(ITEMPOS_INVALID),
       nMenuFlags(MenuFlags::NONE),
       nDefaultItem(0),
@@ -130,8 +130,8 @@ Menu::Menu()
       bCanceled(false),
       bInCallback(false),
       bKilled(false),
-      mpLayoutData(NULL),
-      mpSalMenu(NULL)
+      mpLayoutData(nullptr),
+      mpSalMenu(nullptr)
 {
 }
 
@@ -145,7 +145,7 @@ Menu::~Menu()
     {
         MenuFloatingWindow* pFloat = static_cast<MenuFloatingWindow*>(pWindow.get());
         if( pFloat->pMenu == this )
-            pFloat->pMenu = NULL;
+            pFloat->pMenu = nullptr;
         pWindow->SetAccessible( ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >() );
     }
 
@@ -164,7 +164,7 @@ Menu::~Menu()
     ImplMenuDelData* pDelData = mpFirstDel;
     while ( pDelData )
     {
-        pDelData->mpMenu = NULL;
+        pDelData->mpMenu = nullptr;
         pDelData = pDelData->mpNext;
     }
 
@@ -175,7 +175,7 @@ Menu::~Menu()
     delete mpLayoutData;
 
     // Native-support: destroy SalMenu
-    ImplSetSalMenu( NULL );
+    ImplSetSalMenu( nullptr );
 }
 
 void Menu::CreateAutoMnemonics()
@@ -291,7 +291,7 @@ void Menu::ImplSelect()
 
     // call select
     ImplSVData* pSVData = ImplGetSVData();
-    pSVData->maAppData.mpActivePopupMenu = NULL;        // if new execute in select()
+    pSVData->maAppData.mpActivePopupMenu = nullptr;        // if new execute in select()
     nEventId = Application::PostUserEvent( LINK( this, Menu, ImplCallSelect ) );
 }
 
@@ -395,7 +395,7 @@ void Menu::InsertItem(sal_uInt16 nItemId, const OUString& rStr, MenuItemBits nIt
     NbcInsertItem(nItemId, nItemBits, rStr, this, nPos, rIdent);
 
     vcl::Window* pWin = ImplGetWindow();
-    delete mpLayoutData, mpLayoutData = NULL;
+    delete mpLayoutData, mpLayoutData = nullptr;
     if ( pWin )
     {
         ImplCalcSize( pWin );
@@ -522,7 +522,7 @@ void Menu::InsertItem( const ResId& rResId, sal_uInt16 nPos )
         }
         IncrementRes( GetObjSizeRes( static_cast<RSHEADER_TYPE*>(GetClassRes()) ) );
     }
-    delete mpLayoutData, mpLayoutData = NULL;
+    delete mpLayoutData, mpLayoutData = nullptr;
 }
 
 void Menu::InsertSeparator(const OString &rIdent, sal_uInt16 nPos)
@@ -544,7 +544,7 @@ void Menu::InsertSeparator(const OString &rIdent, sal_uInt16 nPos)
     if( ImplGetSalMenu() && pData && pData->pSalMenuItem )
         ImplGetSalMenu()->InsertItem( pData->pSalMenuItem, nPos );
 
-    delete mpLayoutData, mpLayoutData = NULL;
+    delete mpLayoutData, mpLayoutData = nullptr;
 
     ImplCallEventListeners( VCLEVENT_MENU_INSERTITEM, nPos );
 }
@@ -570,7 +570,7 @@ void Menu::RemoveItem( sal_uInt16 nPos )
         if ( pWin->IsVisible() )
             pWin->Invalidate();
     }
-    delete mpLayoutData, mpLayoutData = NULL;
+    delete mpLayoutData, mpLayoutData = nullptr;
 
     if ( bRemove )
         ImplCallEventListeners( VCLEVENT_MENU_REMOVEITEM, nPos );
@@ -793,7 +793,7 @@ void Menu::SetPopupMenu( sal_uInt16 nItemId, PopupMenu* pMenu )
 
     // #112023# Make sure pStartedFrom does not point to invalid (old) data
     if ( pData->pSubMenu )
-        pData->pSubMenu->pStartedFrom = 0;
+        pData->pSubMenu->pStartedFrom = nullptr;
 
     // set native submenu
     if( ImplGetSalMenu() && pData->pSalMenuItem )
@@ -801,7 +801,7 @@ void Menu::SetPopupMenu( sal_uInt16 nItemId, PopupMenu* pMenu )
         if( pMenu )
             ImplGetSalMenu()->SetSubMenu( pData->pSalMenuItem, pMenu->ImplGetSalMenu(), nPos );
         else
-            ImplGetSalMenu()->SetSubMenu( pData->pSalMenuItem, NULL, nPos );
+            ImplGetSalMenu()->SetSubMenu( pData->pSalMenuItem, nullptr, nPos );
     }
 
     ImplCallEventListeners( VCLEVENT_MENU_SUBMENUCHANGED, nPos );
@@ -814,7 +814,7 @@ PopupMenu* Menu::GetPopupMenu( sal_uInt16 nItemId ) const
     if ( pData )
         return static_cast<PopupMenu*>(pData->pSubMenu);
     else
-        return NULL;
+        return nullptr;
 }
 
 void Menu::SetAccelKey( sal_uInt16 nItemId, const KeyCode& rKeyCode )
@@ -1030,7 +1030,7 @@ void Menu::SetItemText( sal_uInt16 nItemId, const OUString& rStr )
             ImplGetSalMenu()->SetItemText( nPos, pData->pSalMenuItem, rStr );
 
         vcl::Window* pWin = ImplGetWindow();
-        delete mpLayoutData, mpLayoutData = NULL;
+        delete mpLayoutData, mpLayoutData = nullptr;
         if (pWin && IsMenuBar())
         {
             ImplCalcSize( pWin );
@@ -1190,9 +1190,9 @@ OUString Menu::ImplGetHelpText( sal_uInt16 nItemId ) const
         if ( pHelp )
         {
             if (!pData->aCommandStr.isEmpty())
-                pData->aHelpText = pHelp->GetHelpText( pData->aCommandStr, NULL );
+                pData->aHelpText = pHelp->GetHelpText( pData->aCommandStr, nullptr );
             if (pData->aHelpText.isEmpty() && !pData->aHelpId.isEmpty())
-                pData->aHelpText = pHelp->GetHelpText( OStringToOUString( pData->aHelpId, RTL_TEXTENCODING_UTF8 ), NULL );
+                pData->aHelpText = pHelp->GetHelpText( OStringToOUString( pData->aHelpId, RTL_TEXTENCODING_UTF8 ), nullptr );
         }
     }
 
@@ -1286,7 +1286,7 @@ bool Menu::ImplIsVisible( sal_uInt16 nPos ) const
             // always avoid adjacent separators
             size_t nCount = pItemList->size();
             size_t n;
-            MenuItemData* pNextData = NULL;
+            MenuItemData* pNextData = nullptr;
             // search next visible item
             for( n = nPos + 1; n < nCount; n++ )
             {
@@ -1470,7 +1470,7 @@ void Menu::ImplAddDel( ImplMenuDelData& rDel )
 
 void Menu::ImplRemoveDel( ImplMenuDelData& rDel )
 {
-    rDel.mpMenu = NULL;
+    rDel.mpMenu = nullptr;
     if ( mpFirstDel == &rDel )
     {
         mpFirstDel = rDel.mpNext;
@@ -1740,7 +1740,7 @@ static void ImplPaintCheckBackground(vcl::RenderContext& rRenderContext, vcl::Wi
     {
         const StyleSettings& rSettings = rRenderContext.GetSettings().GetStyleSettings();
         Color aColor( i_bHighlight ? rSettings.GetMenuHighlightTextColor() : rSettings.GetHighlightColor() );
-        RenderTools::DrawSelectionBackground(rRenderContext, rWindow, i_rRect, 0, i_bHighlight, true, false, NULL, 2, &aColor);
+        RenderTools::DrawSelectionBackground(rRenderContext, rWindow, i_rRect, 0, i_bHighlight, true, false, nullptr, 2, &aColor);
     }
 }
 
@@ -2028,8 +2028,8 @@ void Menu::ImplPaint(vcl::RenderContext& rRenderContext,
 
                     if (pData->bIsTemporary)
                         nStyle |= DrawTextFlags::Disable;
-                    MetricVector* pVector = bLayout ? &mpLayoutData->m_aUnicodeBoundRects : NULL;
-                    OUString* pDisplayText = bLayout ? &mpLayoutData->m_aDisplayText : NULL;
+                    MetricVector* pVector = bLayout ? &mpLayoutData->m_aUnicodeBoundRects : nullptr;
+                    OUString* pDisplayText = bLayout ? &mpLayoutData->m_aDisplayText : nullptr;
                     if (bLayout)
                     {
                         mpLayoutData->m_aLineIndices.push_back(mpLayoutData->m_aDisplayText.getLength());
@@ -2204,13 +2204,13 @@ void Menu::ImplCallHighlight(sal_uInt16 nItem)
 
 IMPL_LINK_NOARG_TYPED(Menu, ImplCallSelect, void*, void)
 {
-    nEventId = 0;
+    nEventId = nullptr;
     Select();
 }
 
 Menu* Menu::ImplFindSelectMenu()
 {
-    Menu* pSelMenu = nEventId ? this : NULL;
+    Menu* pSelMenu = nEventId ? this : nullptr;
 
     for ( size_t n = GetItemList()->size(); n && !pSelMenu; )
     {
@@ -2225,7 +2225,7 @@ Menu* Menu::ImplFindSelectMenu()
 
 Menu* Menu::ImplFindMenu( sal_uInt16 nItemId )
 {
-    Menu* pSelMenu = NULL;
+    Menu* pSelMenu = nullptr;
 
     for ( size_t n = GetItemList()->size(); n && !pSelMenu; )
     {
@@ -2272,7 +2272,7 @@ void Menu::RemoveDisabledEntries( bool bCheckPopups, bool bRemoveEmptyPopups )
         if ( pItem->eType == MenuItemType::SEPARATOR )
             RemoveItem( nLast );
     }
-    delete mpLayoutData, mpLayoutData = NULL;
+    delete mpLayoutData, mpLayoutData = nullptr;
 }
 
 bool Menu::HasValidEntries( bool bCheckPopups )
@@ -2304,7 +2304,7 @@ void Menu::MenuBarKeyInput(const KeyEvent&)
 
 void Menu::ImplKillLayoutData() const
 {
-    delete mpLayoutData, mpLayoutData = NULL;
+    delete mpLayoutData, mpLayoutData = nullptr;
 }
 
 void Menu::ImplFillLayoutData() const
@@ -2314,12 +2314,12 @@ void Menu::ImplFillLayoutData() const
         mpLayoutData = new MenuLayoutData();
         if (IsMenuBar())
         {
-            ImplPaint(*pWindow, 0, 0, 0, false, true); // FIXME
+            ImplPaint(*pWindow, 0, 0, nullptr, false, true); // FIXME
         }
         else
         {
             MenuFloatingWindow* pFloat = static_cast<MenuFloatingWindow*>(pWindow.get());
-            ImplPaint(*pWindow, pFloat->nScrollerHeight, pFloat->ImplGetStartY(), 0, false, true); //FIXME
+            ImplPaint(*pWindow, pFloat->nScrollerHeight, pFloat->ImplGetStartY(), nullptr, false, true); //FIXME
         }
     }
 }
@@ -2557,7 +2557,7 @@ vcl::Window* MenuBar::ImplCreate(vcl::Window* pParent, vcl::Window* pWindow, Men
         pWindow = pMenuBarWindow = VclPtr<MenuBarWindow>::Create( pParent );
     }
 
-    pMenu->pStartedFrom = 0;
+    pMenu->pStartedFrom = nullptr;
     pMenu->pWindow = pWindow;
     pMenuBarWindow->SetMenu(pMenu);
     long nHeight = pWindow ? pMenu->ImplCalcSize(pWindow).Height() : 0;
@@ -2583,7 +2583,7 @@ void MenuBar::ImplDestroy( MenuBar* pMenu, bool bDelete )
             pMenuWin->KillActivePopup();
         pWindow->disposeOnce();
     }
-    pMenu->pWindow = NULL;
+    pMenu->pWindow = nullptr;
 }
 
 bool MenuBar::ImplHandleKeyEvent( const KeyEvent& rKEvent, bool bFromMenu )
@@ -2769,13 +2769,13 @@ MenuFloatingWindow * PopupMenu::ImplGetFloatingWindow() const {
 }
 
 PopupMenu::PopupMenu()
-    : pRefAutoSubMenu(NULL)
+    : pRefAutoSubMenu(nullptr)
 {
     mpSalMenu = ImplGetSVData()->mpDefInst->CreateMenu(false, this);
 }
 
 PopupMenu::PopupMenu( const ResId& rResId )
-    : pRefAutoSubMenu(NULL)
+    : pRefAutoSubMenu(nullptr)
 {
     mpSalMenu = ImplGetSVData()->mpDefInst->CreateMenu(false, this);
 
@@ -2809,7 +2809,7 @@ PopupMenu::PopupMenu( const ResId& rResId )
 
 PopupMenu::PopupMenu( const PopupMenu& rMenu )
     : Menu(),
-      pRefAutoSubMenu(NULL)
+      pRefAutoSubMenu(nullptr)
 {
     mpSalMenu = ImplGetSVData()->mpDefInst->CreateMenu(false, this);
     *this = rMenu;
@@ -2818,7 +2818,7 @@ PopupMenu::PopupMenu( const PopupMenu& rMenu )
 PopupMenu::~PopupMenu()
 {
     if( pRefAutoSubMenu && *pRefAutoSubMenu == this )
-        *pRefAutoSubMenu = NULL;    // #111060# avoid second delete in ~MenuItemData
+        *pRefAutoSubMenu = nullptr;    // #111060# avoid second delete in ~MenuItemData
 }
 
 void PopupMenu::ClosePopup(Menu* pMenu)
@@ -2909,7 +2909,7 @@ sal_uInt16 PopupMenu::Execute( vcl::Window* pExecWindow, const Rectangle& rRect,
     if (nFlags & PopupMenuFlags::NoHorzPlacement)
         nPopupModeFlags |= FloatWinPopupFlags::NoHorzPlacement;
 
-    return ImplExecute( pExecWindow, rRect, nPopupModeFlags, 0, false );
+    return ImplExecute( pExecWindow, rRect, nPopupModeFlags, nullptr, false );
 }
 
 sal_uInt16 PopupMenu::ImplExecute( vcl::Window* pW, const Rectangle& rRect, FloatWinPopupFlags nPopupModeFlags, Menu* pSFrom, bool bPreSelectFirst )
@@ -2921,7 +2921,7 @@ sal_uInt16 PopupMenu::ImplExecute( vcl::Window* pW, const Rectangle& rRect, Floa
     if( pSFrom && pSFrom->IsMenuBar())
         ((static_cast<MenuBarWindow*>(pSFrom->pWindow.get())))->SetMBWHideAccel(!(static_cast<MenuBarWindow*>(pSFrom->pWindow.get())->GetMBWMenuKey()));
 
-    delete mpLayoutData, mpLayoutData = NULL;
+    delete mpLayoutData, mpLayoutData = nullptr;
 
     ImplSVData* pSVData = ImplGetSVData();
 
@@ -2994,7 +2994,7 @@ sal_uInt16 PopupMenu::ImplExecute( vcl::Window* pW, const Rectangle& rRect, Floa
         {
             OUString aTmpEntryText( ResId( SV_RESID_STRING_NOSELECTIONPOSSIBLE, *pResMgr ) );
 
-            MenuItemData* pData = NbcInsertItem(0xFFFF, MenuItemBits::NONE, aTmpEntryText, NULL, 0xFFFF, OString());
+            MenuItemData* pData = NbcInsertItem(0xFFFF, MenuItemBits::NONE, aTmpEntryText, nullptr, 0xFFFF, OString());
             size_t nPos = 0;
             pData = pItemList->GetData( pData->nId, nPos );
             assert(pData);
@@ -3079,7 +3079,7 @@ sal_uInt16 PopupMenu::ImplExecute( vcl::Window* pW, const Rectangle& rRect, Floa
             pWin->StopExecute();
             pWin->doShutdown();
             pWindow->doLazyDelete();
-            pWindow = NULL;
+            pWindow = nullptr;
             return nSelectedId;
         }
         else
@@ -3157,7 +3157,7 @@ sal_uInt16 PopupMenu::ImplExecute( vcl::Window* pW, const Rectangle& rRect, Floa
         }
         pWin->doShutdown();
         pWindow->doLazyDelete();
-        pWindow = NULL;
+        pWindow = nullptr;
 
         // is there still Select?
         Menu* pSelect = ImplFindSelectMenu();
@@ -3165,7 +3165,7 @@ sal_uInt16 PopupMenu::ImplExecute( vcl::Window* pW, const Rectangle& rRect, Floa
         {
             // Select should be called prior to leaving execute in a popup menu!
             Application::RemoveUserEvent( pSelect->nEventId );
-            pSelect->nEventId = 0;
+            pSelect->nEventId = nullptr;
             pSelect->Select();
         }
     }
@@ -3222,8 +3222,8 @@ long PopupMenu::ImplCalcHeight( sal_uInt16 nEntries ) const
 }
 
 ImplMenuDelData::ImplMenuDelData( const Menu* pMenu )
-: mpNext( 0 )
-, mpMenu( 0 )
+: mpNext( nullptr )
+, mpMenu( nullptr )
 {
     if( pMenu )
         const_cast< Menu* >( pMenu )->ImplAddDel( *this );
@@ -3242,7 +3242,7 @@ struct MenuInvalidateListeners : public vcl::DeletionNotifier
     std::vector<Link<LinkParamNone*,void>>   m_aListeners;
 };
 
-static MenuInvalidateListeners* pMenuInvalidateListeners = NULL;
+static MenuInvalidateListeners* pMenuInvalidateListeners = nullptr;
 
 void AddMenuInvalidateListener(const Link<LinkParamNone*,void>& rLink)
 {
diff --git a/vcl/source/window/menubarwindow.cxx b/vcl/source/window/menubarwindow.cxx
index 67eba4eed45f..32093142d5b6 100644
--- a/vcl/source/window/menubarwindow.cxx
+++ b/vcl/source/window/menubarwindow.cxx
@@ -124,8 +124,8 @@ MenuBarWindow::MenuBarWindow( vcl::Window* pParent ) :
     aHideBtn(VclPtr<PushButton>::Create(this, WB_NOPOINTERFOCUS | WB_SMALLSTYLE | WB_RECTSTYLE))
 {
     SetType(WINDOW_MENUBARWINDOW);
-    pMenu = NULL;
-    pActivePopup = NULL;
+    pMenu = nullptr;
+    pActivePopup = nullptr;
     nSaveFocusId = 0;
     nHighlightedItem = ITEMPOS_INVALID;
     nRolloveredItem = ITEMPOS_INVALID;
@@ -287,7 +287,7 @@ IMPL_LINK_TYPED( MenuBarWindow, ShowHideListener, VclWindowEvent&, rEvent, void
 
 void MenuBarWindow::ImplCreatePopup( bool bPreSelectFirst )
 {
-    MenuItemData* pItemData = pMenu ? pMenu->GetItemList()->GetDataFromPos( nHighlightedItem ) : NULL;
+    MenuItemData* pItemData = pMenu ? pMenu->GetItemList()->GetDataFromPos( nHighlightedItem ) : nullptr;
     if ( pItemData )
     {
         bIgnoreFirstMove = true;
@@ -300,7 +300,7 @@ void MenuBarWindow::ImplCreatePopup( bool bPreSelectFirst )
         {
             pActivePopup = static_cast<PopupMenu*>(pItemData->pSubMenu);
             long nX = 0;
-            MenuItemData* pData = 0;
+            MenuItemData* pData = nullptr;
             for ( sal_uLong n = 0; n < nHighlightedItem; n++ )
             {
                 pData = pMenu->GetItemList()->GetDataFromPos( n );
@@ -353,9 +353,9 @@ void MenuBarWindow::KillActivePopup()
             pActivePopup->ImplGetFloatingWindow()->StopExecute();
             pActivePopup->ImplGetFloatingWindow()->doShutdown();
             pActivePopup->pWindow->doLazyDelete();
-            pActivePopup->pWindow = NULL;
+            pActivePopup->pWindow = nullptr;
         }
-        pActivePopup = 0;
+        pActivePopup = nullptr;
     }
 }
 
@@ -544,7 +544,7 @@ static int ImplGetTopDockingAreaHeight( vcl::Window *pWindow )
                 vcl::Window *pChildWin = pWin->GetWindow( GetWindowType::FirstChild ); //mpWindowImpl->mpFirstChild;
                 while( pChildWin )
                 {
-                    DockingAreaWindow *pDockingArea = NULL;
+                    DockingAreaWindow *pDockingArea = nullptr;
                     if ( pChildWin->GetType() == WINDOW_DOCKINGAREA )
                         pDockingArea = static_cast< DockingAreaWindow* >( pChildWin );
 
diff --git a/vcl/source/window/menufloatingwindow.cxx b/vcl/source/window/menufloatingwindow.cxx
index 0fff6618d878..327af121ba1d 100644
--- a/vcl/source/window/menufloatingwindow.cxx
+++ b/vcl/source/window/menufloatingwindow.cxx
@@ -31,7 +31,7 @@ MenuFloatingWindow::MenuFloatingWindow( Menu* pMen, vcl::Window* pParent, WinBit
 {
     mpWindowImpl->mbMenuFloatingWindow= true;
     pMenu               = pMen;
-    pActivePopup        = 0;
+    pActivePopup        = nullptr;
     nSaveFocusId        = 0;
     bInExecute          = false;
     bScrollMenu         = false;
@@ -98,7 +98,7 @@ void MenuFloatingWindow::doShutdown()
             Rectangle aInvRect( GetWindowExtentsRelative( GetParent() ) );
             GetParent()->Invalidate( aInvRect );
         }
-        pMenu = NULL;
+        pMenu = nullptr;
         RemoveEventListener( LINK( this, MenuFloatingWindow, ShowHideListener ) );
     }
 }
@@ -231,7 +231,7 @@ void MenuFloatingWindow::ImplHighlightItem( const MouseEvent& rMEvt, bool bMBDow
 
                         if ( bPopupArea && bAllowNewPopup )
                         {
-                            HighlightChanged( NULL );
+                            HighlightChanged( nullptr );
                         }
                     }
                     else
@@ -243,7 +243,7 @@ void MenuFloatingWindow::ImplHighlightItem( const MouseEvent& rMEvt, bool bMBDow
                         else if ( pItemData->nBits & MenuItemBits::POPUPSELECT )
                         {
                             if ( bPopupArea && ( pActivePopup != pItemData->pSubMenu ) )
-                                HighlightChanged( NULL );
+                                HighlightChanged( nullptr );
                         }
                     }
                     bHighlighted = true;
@@ -284,7 +284,7 @@ IMPL_LINK_NOARG_TYPED(MenuFloatingWindow, PopupEnd, FloatingWindow*, void)
     }
 
     if ( pM )
-        pM->pStartedFrom = 0;
+        pM->pStartedFrom = nullptr;
 }
 
 IMPL_LINK_NOARG_TYPED(MenuFloatingWindow, AutoScroll, Timer *, void)
@@ -311,7 +311,7 @@ IMPL_LINK_TYPED( MenuFloatingWindow, HighlightChanged, Timer*, pTimer, void )
         {
             pActivePopup = static_cast<PopupMenu*>(pItemData->pSubMenu);
             long nY = nScrollerHeight+ImplGetStartY();
-            MenuItemData* pData = 0;
+            MenuItemData* pData = nullptr;
             for ( sal_uLong n = 0; n < nHighlightedItem; n++ )
             {
                 pData = pMenu->pItemList->GetDataFromPos( n );
@@ -394,7 +394,7 @@ void MenuFloatingWindow::Execute()
     while ( bInExecute )
         Application::Yield();
 
-    pSVData->maAppData.mpActivePopupMenu = NULL;
+    pSVData->maAppData.mpActivePopupMenu = nullptr;
 }
 
 void MenuFloatingWindow::StopExecute( sal_uLong nFocusId )
@@ -437,7 +437,7 @@ void MenuFloatingWindow::KillActivePopup( PopupMenu* pThisOnly )
         // For all actions pActivePopup = 0, if e.g.
         // PopupModeEndHdl the popups to destroy were called synchronous
         PopupMenu* pPopup = pActivePopup;
-        pActivePopup = NULL;
+        pActivePopup = nullptr;
         pPopup->bInCallback = true;
         pPopup->Deactivate();
         pPopup->bInCallback = false;
@@ -446,7 +446,7 @@ void MenuFloatingWindow::KillActivePopup( PopupMenu* pThisOnly )
             pPopup->ImplGetFloatingWindow()->StopExecute();
             pPopup->ImplGetFloatingWindow()->doShutdown();
             pPopup->pWindow->doLazyDelete();
-            pPopup->pWindow = NULL;
+            pPopup->pWindow = nullptr;
 
             Update();
         }
@@ -455,7 +455,7 @@ void MenuFloatingWindow::KillActivePopup( PopupMenu* pThisOnly )
 
 void MenuFloatingWindow::EndExecute()
 {
-    Menu* pStart = pMenu ? pMenu->ImplGetStartMenu() : NULL;
+    Menu* pStart = pMenu ? pMenu->ImplGetStartMenu() : nullptr;
     sal_uLong nFocusId = 0;
     if (pStart)
         nFocusId = pStart->DeactivateMenuBar(nFocusId);
@@ -517,7 +517,7 @@ void MenuFloatingWindow::MouseButtonDown( const MouseEvent& rMEvt )
 
 void MenuFloatingWindow::MouseButtonUp( const MouseEvent& rMEvt )
 {
-    MenuItemData* pData = pMenu ? pMenu->GetItemList()->GetDataFromPos( nHighlightedItem ) : NULL;
+    MenuItemData* pData = pMenu ? pMenu->GetItemList()->GetDataFromPos( nHighlightedItem ) : nullptr;
     // nMBDownPos store in local variable and reset immediately,
     // as it will be too late after EndExecute
     sal_uInt16 _nMBDownPos = nMBDownPos;
@@ -548,7 +548,7 @@ void MenuFloatingWindow::MouseMove( const MouseEvent& rMEvt )
     if ( rMEvt.IsLeaveWindow() )
     {
         // #102461# do not remove highlight if a popup menu is open at this position
-        MenuItemData* pData = pMenu ? pMenu->pItemList->GetDataFromPos( nHighlightedItem ) : NULL;
+        MenuItemData* pData = pMenu ? pMenu->pItemList->GetDataFromPos( nHighlightedItem ) : nullptr;
         // close popup with some delayed if we leave somewhere else
         if( pActivePopup && pData && pData->pSubMenu != pActivePopup )
             pActivePopup->ImplGetFloatingWindow()->aSubmenuCloseTimer.Start();
@@ -1055,7 +1055,7 @@ void MenuFloatingWindow::KeyInput( const KeyEvent& rKEvent )
                     MenuItemData* pData = pMenu->GetItemList()->GetDataFromPos( nHighlightedItem );
                     if ( pData && pData->pSubMenu )
                     {
-                        HighlightChanged( 0 );
+                        HighlightChanged( nullptr );
                         bDone = true;
                     }
                 }
@@ -1079,7 +1079,7 @@ void MenuFloatingWindow::KeyInput( const KeyEvent& rKEvent )
                 if ( pData && pData->bEnabled )
                 {
                     if ( pData->pSubMenu )
-                        HighlightChanged( 0 );
+                        HighlightChanged( nullptr );
                     else
                         EndExecute();
                 }
@@ -1107,7 +1107,7 @@ void MenuFloatingWindow::KeyInput( const KeyEvent& rKEvent )
             sal_uInt16 nPos = 0;
             sal_uInt16 nDuplicates = 0;
             MenuItemData* pData = (nCharCode && pMenu) ?
-                pMenu->GetItemList()->SearchItem(nCharCode, rKEvent.GetKeyCode(), nPos, nDuplicates, nHighlightedItem) : NULL;
+                pMenu->GetItemList()->SearchItem(nCharCode, rKEvent.GetKeyCode(), nPos, nDuplicates, nHighlightedItem) : nullptr;
             bool bConsume = false;
             bool accel = ImplGetSVData()->maNWFData.mbEnableAccel;
             if (pData && accel)
@@ -1122,7 +1122,7 @@ void MenuFloatingWindow::KeyInput( const KeyEvent& rKEvent )
                 if ( pData->pSubMenu || nDuplicates > 1 )
                 {
                     ChangeHighlightItem( nPos, false );
-                    HighlightChanged( 0 );
+                    HighlightChanged( nullptr );
                 }
                 else
                 {
@@ -1212,7 +1212,7 @@ void MenuFloatingWindow::RequestHelp( const HelpEvent& rHEvt )
     {
         nHighlightedItem = ITEMPOS_INVALID;
         EndExecute();
-        pW = NULL;
+        pW = nullptr;
     }
 
     if( !ImplHandleHelpEvent( pW, pM, nId, rHEvt, aHighlightRect ) )
diff --git a/vcl/source/window/menufloatingwindow.hxx b/vcl/source/window/menufloatingwindow.hxx
index 8797d4ba9361..6fe08e4f8572 100644
--- a/vcl/source/window/menufloatingwindow.hxx
+++ b/vcl/source/window/menufloatingwindow.hxx
@@ -79,7 +79,7 @@ protected:
     long ImplGetStartY() const;
     Rectangle ImplGetItemRect( sal_uInt16 nPos );
     void RenderHighlightItem( vcl::RenderContext& rRenderContext, sal_uInt16 nPos, bool bHighlight );
-    long GetInitialItemY( long *pOptStartY = NULL ) const;
+    long GetInitialItemY( long *pOptStartY = nullptr ) const;
     void InvalidateItem( sal_uInt16 nPos );
 
 public:
@@ -113,7 +113,7 @@ public:
     void EndExecute( sal_uInt16 nSelectId );
 
     PopupMenu* GetActivePopup() const  { return pActivePopup; }
-    void KillActivePopup( PopupMenu* pThisOnly = NULL );
+    void KillActivePopup( PopupMenu* pThisOnly = nullptr );
 
     void ChangeHighlightItem(sal_uInt16 n, bool bStartPopupTimer);
     sal_uInt16 GetHighlightedItem() const { return nHighlightedItem; }
diff --git a/vcl/source/window/menuitemlist.cxx b/vcl/source/window/menuitemlist.cxx
index c104ba8a1ef8..d1042b4fb30b 100644
--- a/vcl/source/window/menuitemlist.cxx
+++ b/vcl/source/window/menuitemlist.cxx
@@ -36,9 +36,9 @@ MenuItemData::~MenuItemData()
         aUserValueReleaseFunc(nUserValue);
     if( pAutoSubMenu )
     {
-        static_cast<PopupMenu*>(pAutoSubMenu)->pRefAutoSubMenu = NULL;
+        static_cast<PopupMenu*>(pAutoSubMenu)->pRefAutoSubMenu = nullptr;
         delete pAutoSubMenu;
-        pAutoSubMenu = NULL;
+        pAutoSubMenu = nullptr;
     }
     if( pSalMenuItem )
         ImplGetSVData()->mpDefInst->DestroyMenuItem( pSalMenuItem );
@@ -66,8 +66,8 @@ MenuItemData* MenuItemList::Insert(
     pData->sIdent           = rIdent;
     pData->eType            = eType;
     pData->nBits            = nBits;
-    pData->pSubMenu         = NULL;
-    pData->pAutoSubMenu     = NULL;
+    pData->pSubMenu         = nullptr;
+    pData->pAutoSubMenu     = nullptr;
     pData->nUserValue       = 0;
     pData->bChecked         = false;
     pData->bEnabled         = true;
@@ -102,8 +102,8 @@ void MenuItemList::InsertSeparator(const OString &rIdent, size_t nPos)
     pData->sIdent           = rIdent;
     pData->eType            = MenuItemType::SEPARATOR;
     pData->nBits            = MenuItemBits::NONE;
-    pData->pSubMenu         = NULL;
-    pData->pAutoSubMenu     = NULL;
+    pData->pSubMenu         = nullptr;
+    pData->pAutoSubMenu     = nullptr;
     pData->nUserValue       = 0;
     pData->bChecked         = false;
     pData->bEnabled         = true;
@@ -116,7 +116,7 @@ void MenuItemList::InsertSeparator(const OString &rIdent, size_t nPos)
     aSalMIData.nId = 0;
     aSalMIData.eType = MenuItemType::SEPARATOR;
     aSalMIData.nBits = MenuItemBits::NONE;
-    aSalMIData.pMenu = NULL;
+    aSalMIData.pMenu = nullptr;
     aSalMIData.aText.clear();
     aSalMIData.aImage = Image();
 
@@ -149,7 +149,7 @@ MenuItemData* MenuItemList::GetData( sal_uInt16 nSVId, size_t& rPos ) const
             return maItemList[ i ];
         }
     }
-    return NULL;
+    return nullptr;
 }
 
 MenuItemData* MenuItemList::SearchItem(
@@ -221,7 +221,7 @@ MenuItemData* MenuItemList::SearchItem(
         }
     }
 
-    return NULL;
+    return nullptr;
 }
 
 size_t MenuItemList::GetItemCount( sal_Unicode cSelectChar ) const
diff --git a/vcl/source/window/menuitemlist.hxx b/vcl/source/window/menuitemlist.hxx
index 6f2b2631bdef..3f7f8d2d6166 100644
--- a/vcl/source/window/menuitemlist.hxx
+++ b/vcl/source/window/menuitemlist.hxx
@@ -62,28 +62,28 @@ struct MenuItemData
         : nId(0)
         , eType(MenuItemType::DONTKNOW)
         , nBits(MenuItemBits::NONE)
-        , pSubMenu(NULL)
-        , pAutoSubMenu(NULL)
+        , pSubMenu(nullptr)
+        , pAutoSubMenu(nullptr)
         , nUserValue(0)
-        , aUserValueReleaseFunc(0)
+        , aUserValueReleaseFunc(nullptr)
         , bChecked(false)
         , bEnabled(false)
         , bVisible(false)
         , bIsTemporary(false)
         , bMirrorMode(false)
         , nItemImageAngle(0)
-        , pSalMenuItem(NULL)
+        , pSalMenuItem(nullptr)
     {
     }
     MenuItemData( const OUString& rStr, const Image& rImage )
         : nId(0)
         , eType(MenuItemType::DONTKNOW)
         , nBits(MenuItemBits::NONE)
-        , pSubMenu(NULL)
-        , pAutoSubMenu(NULL)
+        , pSubMenu(nullptr)
+        , pAutoSubMenu(nullptr)
         , aText(rStr)
         , nUserValue(0)
-        , aUserValueReleaseFunc(0)
+        , aUserValueReleaseFunc(nullptr)
         , aImage(rImage)
         , bChecked(false)
         , bEnabled(false)
@@ -91,7 +91,7 @@ struct MenuItemData
         , bIsTemporary(false)
         , bMirrorMode(false)
         , nItemImageAngle(0)
-        , pSalMenuItem(NULL)
+        , pSalMenuItem(nullptr)
     {
     }
     ~MenuItemData();
@@ -134,7 +134,7 @@ public:
                     }
     MenuItemData*   GetDataFromPos( size_t nPos ) const
                     {
-                        return ( nPos < maItemList.size() ) ? maItemList[ nPos ] : NULL;
+                        return ( nPos < maItemList.size() ) ? maItemList[ nPos ] : nullptr;
                     }
 
     MenuItemData*   SearchItem(
diff --git a/vcl/source/window/menuwindow.cxx b/vcl/source/window/menuwindow.cxx
index e915c33e4c07..72a1baecbb3f 100644
--- a/vcl/source/window/menuwindow.cxx
+++ b/vcl/source/window/menuwindow.cxx
@@ -99,9 +99,9 @@ bool MenuWindow::ImplHandleHelpEvent(vcl::Window* pMenuWindow, Menu* pMenu, sal_
                 aHelpId = OOO_HELP_INDEX;
 
             if ( !aCommand.isEmpty() )
-                pHelp->Start( aCommand, NULL );
+                pHelp->Start( aCommand, nullptr );
             else
-                pHelp->Start( OStringToOUString( aHelpId, RTL_TEXTENCODING_UTF8 ), NULL );
+                pHelp->Start( OStringToOUString( aHelpId, RTL_TEXTENCODING_UTF8 ), nullptr );
         }
         bDone = true;
     }
diff --git a/vcl/source/window/mnemonicengine.cxx b/vcl/source/window/mnemonicengine.cxx
index f9f74398e172..6901d1aa4ed1 100644
--- a/vcl/source/window/mnemonicengine.cxx
+++ b/vcl/source/window/mnemonicengine.cxx
@@ -47,7 +47,7 @@ namespace vcl
             OUString sEntryText;
             const void* pSearchEntry = _rEntryList.FirstSearchEntry( sEntryText );
 
-            const void* pFirstFoundEntry = NULL;
+            const void* pFirstFoundEntry = nullptr;
             bool bCheckingAmbiguity = false;
             const void* pStartedWith = pSearchEntry;
             while ( pSearchEntry )
diff --git a/vcl/source/window/mouse.cxx b/vcl/source/window/mouse.cxx
index ad6c460d6d91..198e4cde7460 100644
--- a/vcl/source/window/mouse.cxx
+++ b/vcl/source/window/mouse.cxx
@@ -160,12 +160,12 @@ void Window::ImplCallMouseMove( sal_uInt16 nMouseCode, bool bModChanged )
 void Window::ImplGenerateMouseMove()
 {
     if ( !mpWindowImpl->mpFrameData->mnMouseMoveId )
-        mpWindowImpl->mpFrameData->mnMouseMoveId = Application::PostUserEvent( LINK( mpWindowImpl->mpFrameWindow, Window, ImplGenerateMouseMoveHdl ), NULL, true );
+        mpWindowImpl->mpFrameData->mnMouseMoveId = Application::PostUserEvent( LINK( mpWindowImpl->mpFrameWindow, Window, ImplGenerateMouseMoveHdl ), nullptr, true );
 }
 
 IMPL_LINK_NOARG_TYPED(Window, ImplGenerateMouseMoveHdl, void*, void)
 {
-    mpWindowImpl->mpFrameData->mnMouseMoveId = 0;
+    mpWindowImpl->mpFrameData->mnMouseMoveId = nullptr;
     vcl::Window* pCaptureWin = ImplGetSVData()->maWinData.mpCaptureWin;
     if( ! pCaptureWin ||
         (pCaptureWin->mpWindowImpl && pCaptureWin->mpWindowImpl->mpFrame == mpWindowImpl->mpFrame)
@@ -384,7 +384,7 @@ void Window::ImplGrabFocus( GetFocusFlags nFlags )
                 if ( !ImplCallPreNotify( aNEvt ) && !aDogTag.IsDead() )
                     CompatGetFocus();
                 if( !aDogTag.IsDead() )
-                    ImplCallActivateListeners( (pOldFocusWindow && ! aOldFocusDel.IsDead()) ? pOldFocusWindow : NULL );
+                    ImplCallActivateListeners( (pOldFocusWindow && ! aOldFocusDel.IsDead()) ? pOldFocusWindow : nullptr );
                 if( !aDogTag.IsDead() )
                 {
                     mpWindowImpl->mnGetFocusFlags = GetFocusFlags::NONE;
@@ -473,7 +473,7 @@ void Window::ReleaseMouse()
 
     if ( pSVData->maWinData.mpCaptureWin.get() == this )
     {
-        pSVData->maWinData.mpCaptureWin = NULL;
+        pSVData->maWinData.mpCaptureWin = nullptr;
         mpWindowImpl->mpFrame->CaptureMouse( false );
         ImplGenerateMouseMove();
     }
diff --git a/vcl/source/window/msgbox.cxx b/vcl/source/window/msgbox.cxx
index 659c3fe33449..e892c1d3c7be 100644
--- a/vcl/source/window/msgbox.cxx
+++ b/vcl/source/window/msgbox.cxx
@@ -52,10 +52,10 @@ static void ImplInitMsgBoxImageList()
 
 void MessBox::ImplInitMessBoxData()
 {
-    mpVCLMultiLineEdit  = NULL;
-    mpFixedImage        = NULL;
+    mpVCLMultiLineEdit  = nullptr;
+    mpFixedImage        = nullptr;
     mbHelpBtn           = false;
-    mpCheckBox          = NULL;
+    mpCheckBox          = nullptr;
     mbCheck             = false;
 }
 
diff --git a/vcl/source/window/openglwin.cxx b/vcl/source/window/openglwin.cxx
index 9af4c0ff399b..3f95894181d1 100644
--- a/vcl/source/window/openglwin.cxx
+++ b/vcl/source/window/openglwin.cxx
@@ -42,7 +42,7 @@ OpenGLWindowImpl::~OpenGLWindowImpl()
 OpenGLWindow::OpenGLWindow(vcl::Window* pParent):
     Window(pParent, 0),
     mxImpl(new OpenGLWindowImpl(this)),
-    mpRenderer(NULL)
+    mpRenderer(nullptr)
 {
 }
 
@@ -55,7 +55,7 @@ void OpenGLWindow::dispose()
 {
     if(mpRenderer)
         mpRenderer->contextDestroyed();
-    mpRenderer = NULL;
+    mpRenderer = nullptr;
     mxImpl.reset();
     Window::dispose();
 }
diff --git a/vcl/source/window/paint.cxx b/vcl/source/window/paint.cxx
index ade79ba0d77d..6dd4da85a2ba 100644
--- a/vcl/source/window/paint.cxx
+++ b/vcl/source/window/paint.cxx
@@ -215,7 +215,7 @@ public:
 
 PaintHelper::PaintHelper(vcl::Window *pWindow, sal_uInt16 nPaintFlags)
     : m_pWindow(pWindow)
-    , m_pChildRegion(NULL)
+    , m_pChildRegion(nullptr)
     , m_nPaintFlags(nPaintFlags)
     , m_bPop(false)
     , m_bRestoreCursor(false)
@@ -519,7 +519,7 @@ void Window::PopPaintHelper(PaintHelper *pHelper)
     }
     mpWindowImpl->mbInPaint = false;
     mbInitClipRegion = true;
-    mpWindowImpl->mpPaintRegion = NULL;
+    mpWindowImpl->mpPaintRegion = nullptr;
     if (mpWindowImpl->mpCursor)
         mpWindowImpl->mpCursor->ImplResume(pHelper->GetRestoreCursor());
 }
@@ -628,7 +628,7 @@ void Window::ImplCallOverlapPaint()
         // - RTL - notify ImplCallPaint to check for re-mirroring (CHECKRTL)
         //         because we were called from the Sal layer
         OutputDevice::PaintScope aScope( GetOutDev() );
-        ImplCallPaint(NULL, mpWindowImpl->mnPaintFlags /*| IMPL_PAINT_CHECKRTL */);
+        ImplCallPaint(nullptr, mpWindowImpl->mnPaintFlags /*| IMPL_PAINT_CHECKRTL */);
     }
 }
 
@@ -671,12 +671,12 @@ IMPL_LINK_NOARG_TYPED(Window, ImplHandleResizeTimerHdl, Idle *, void)
         ImplCallResize();
         if( ImplDoTiledRendering() )
         {
-            ImplHandlePaintHdl(NULL);
+            ImplHandlePaintHdl(nullptr);
         }
         else if( mpWindowImpl->mpFrameData->maPaintIdle.IsActive() )
         {
             mpWindowImpl->mpFrameData->maPaintIdle.Stop();
-            mpWindowImpl->mpFrameData->maPaintIdle.GetIdleHdl().Call( NULL );
+            mpWindowImpl->mpFrameData->maPaintIdle.GetIdleHdl().Call( nullptr );
         }
     }
 }
@@ -811,7 +811,7 @@ void Window::ImplInvalidate( const vcl::Region* pRegion, InvalidateFlags nFlags
     if ( (nFlags & InvalidateFlags::NoChildren) && mpWindowImpl->mpFirstChild )
         bInvalidateAll = false;
     if ( bInvalidateAll )
-        ImplInvalidateFrameRegion( NULL, nFlags );
+        ImplInvalidateFrameRegion( nullptr, nFlags );
     else
     {
         Rectangle   aRect( Point( mnOutOffX, mnOutOffY ), Size( mnOutWidth, mnOutHeight ) );
@@ -970,7 +970,7 @@ void Window::ImplValidate( const vcl::Region* pRegion, ValidateFlags nFlags )
     if ( (nFlags & ValidateFlags::NoChildren) && mpWindowImpl->mpFirstChild )
         bValidateAll = false;
     if ( bValidateAll )
-        ImplValidateFrameRegion( NULL, nFlags );
+        ImplValidateFrameRegion( nullptr, nFlags );
     else
     {
         Rectangle   aRect( Point( mnOutOffX, mnOutOffY ), Size( mnOutWidth, mnOutHeight ) );
@@ -1017,7 +1017,7 @@ void Window::ImplUpdateAll( bool bOverlapWindows )
     else
     {
         if (pWindow->mpWindowImpl->mnPaintFlags & (IMPL_PAINT_PAINT | IMPL_PAINT_PAINTCHILDREN))
-            pWindow->ImplCallPaint(NULL, pWindow->mpWindowImpl->mnPaintFlags);
+            pWindow->ImplCallPaint(nullptr, pWindow->mpWindowImpl->mnPaintFlags);
     }
 
     if ( bFlush )
@@ -1208,8 +1208,8 @@ void Window::Invalidate( InvalidateFlags nFlags )
     if ( !comphelper::LibreOfficeKit::isActive() && (!IsDeviceOutputNecessary() || !mnOutWidth || !mnOutHeight) )
         return;
 
-    ImplInvalidate( NULL, nFlags );
-    LogicInvalidate(0);
+    ImplInvalidate( nullptr, nFlags );
+    LogicInvalidate(nullptr);
 }
 
 void Window::Invalidate( const Rectangle& rRect, InvalidateFlags nFlags )
@@ -1235,8 +1235,8 @@ void Window::Invalidate( const vcl::Region& rRegion, InvalidateFlags nFlags )
 
     if ( rRegion.IsNull() )
     {
-        ImplInvalidate( NULL, nFlags );
-        LogicInvalidate(0);
+        ImplInvalidate( nullptr, nFlags );
+        LogicInvalidate(nullptr);
     }
     else
     {
@@ -1255,7 +1255,7 @@ void Window::Validate( ValidateFlags nFlags )
     if ( !comphelper::LibreOfficeKit::isActive() && (!IsDeviceOutputNecessary() || !mnOutWidth || !mnOutHeight) )
         return;
 
-    ImplValidate( NULL, nFlags );
+    ImplValidate( nullptr, nFlags );
 }
 
 bool Window::HasPaintEvent() const
@@ -1345,7 +1345,7 @@ void Window::Update()
              pUpdateOverlapWindow = pUpdateOverlapWindow->mpWindowImpl->mpNext;
          }
 
-        pUpdateWindow->ImplCallPaint(NULL, pUpdateWindow->mpWindowImpl->mnPaintFlags);
+        pUpdateWindow->ImplCallPaint(nullptr, pUpdateWindow->mpWindowImpl->mnPaintFlags);
 
         if (aDogTag.IsDead())
            return;
@@ -1485,7 +1485,7 @@ void Window::PaintToDevice( OutputDevice* pDev, const Point& rPos, const Size& /
     DBG_ASSERT( ! pDev->HasMirroredGraphics(), "PaintToDevice to mirroring graphics" );
     DBG_ASSERT( ! pDev->IsRTLEnabled(), "PaintToDevice to mirroring device" );
 
-    vcl::Window* pRealParent = NULL;
+    vcl::Window* pRealParent = nullptr;
     if( ! mpWindowImpl->mbVisible )
     {
         vcl::Window* pTempParent = ImplGetDefaultWindow();
diff --git a/vcl/source/window/printdlg.cxx b/vcl/source/window/printdlg.cxx
index ef58f37eea17..71c175b52dfc 100644
--- a/vcl/source/window/printdlg.cxx
+++ b/vcl/source/window/printdlg.cxx
@@ -571,7 +571,7 @@ void PrintDialog::OutputOptPage::storeToSettings()
 
 PrintDialog::PrintDialog( vcl::Window* i_pParent, const std::shared_ptr<PrinterController>& i_rController )
     : ModalDialog(i_pParent, "PrintDialog", "vcl/ui/printdialog.ui")
-    , mpCustomOptionsUIBuilder(NULL)
+    , mpCustomOptionsUIBuilder(nullptr)
     , maPController( i_rController )
     , maNUpPage(m_pUIBuilder)
     , maJobPage(m_pUIBuilder)
@@ -1002,7 +1002,7 @@ void PrintDialog::setupOptionalUI()
             if( pVal )
                 pVal->Value >>= bVal;
             maNUpPage.mpBrochureBtn->Check( bVal );
-            maNUpPage.mpBrochureBtn->Enable( maPController->isUIOptionEnabled( aPropertyName ) && pVal != NULL );
+            maNUpPage.mpBrochureBtn->Enable( maPController->isUIOptionEnabled( aPropertyName ) && pVal != nullptr );
             maNUpPage.mpBrochureBtn->SetToggleHdl( LINK( this, PrintDialog, ToggleRadioHdl ) );
 
             maPropertyToWindowMap[ aPropertyName ].push_back( maNUpPage.mpBrochureBtn );
@@ -1671,7 +1671,7 @@ IMPL_LINK_TYPED( PrintDialog, ModifyHdl, Edit&, rEdit, void )
 
 PropertyValue* PrintDialog::getValueForWindow( vcl::Window* i_pWindow ) const
 {
-    PropertyValue* pVal = NULL;
+    PropertyValue* pVal = nullptr;
     auto it = maControlToPropertyMap.find( i_pWindow );
     if( it != maControlToPropertyMap.end() )
     {
diff --git a/vcl/source/window/scrwnd.cxx b/vcl/source/window/scrwnd.cxx
index 88e1cf1106d7..b438d1e6c009 100644
--- a/vcl/source/window/scrwnd.cxx
+++ b/vcl/source/window/scrwnd.cxx
@@ -91,7 +91,7 @@ void ImplWheelWindow::dispose()
 {
     ImplStop();
     delete mpTimer;
-    mpTimer = NULL;
+    mpTimer = nullptr;
 
     FloatingWindow::dispose();
 }
@@ -123,7 +123,7 @@ void ImplWheelWindow::ImplCreateImageList()
     ResMgr* pResMgr = ImplGetResMgr();
     if( pResMgr )
         maImgList.InsertFromHorizontalBitmap
-            ( ResId( SV_RESID_BITMAP_SCROLLBMP, *pResMgr ), 6, NULL );
+            ( ResId( SV_RESID_BITMAP_SCROLLBMP, *pResMgr ), 6, nullptr );
 }
 
 void ImplWheelWindow::ImplSetWheelMode( sal_uLong nWheelMode )
diff --git a/vcl/source/window/split.cxx b/vcl/source/window/split.cxx
index 115ec625e159..de21f161c778 100644
--- a/vcl/source/window/split.cxx
+++ b/vcl/source/window/split.cxx
@@ -52,7 +52,7 @@ namespace
 void Splitter::ImplInitSplitterData()
 {
     ImplGetWindowImpl()->mbSplitter        = true;
-    mpRefWin          = NULL;
+    mpRefWin          = nullptr;
     mnSplitPos        = 0;
     mnLastSplitPos    = 0;
     mnStartSplitPos   = 0;
@@ -88,7 +88,7 @@ void Splitter::ImplInitHorVer(bool bNew)
 
 void Splitter::ImplInit( vcl::Window* pParent, WinBits nWinStyle )
 {
-    Window::ImplInit( pParent, nWinStyle, NULL );
+    Window::ImplInit( pParent, nWinStyle, nullptr );
 
     mpRefWin = pParent;
 
@@ -183,7 +183,7 @@ Splitter* Splitter::ImplFindSibling()
 {
     // look for another splitter with the same parent but different orientation
     vcl::Window *pWin = GetParent()->GetWindow( GetWindowType::FirstChild );
-    Splitter *pSplitter = NULL;
+    Splitter *pSplitter = nullptr;
     while( pWin )
     {
         if( pWin->ImplIsSplitter() )
@@ -194,7 +194,7 @@ Splitter* Splitter::ImplFindSibling()
         }
         pWin = pWin->GetWindow( GetWindowType::Next );
     }
-    return NULL;
+    return nullptr;
 }
 
 bool Splitter::ImplSplitterActive()
diff --git a/vcl/source/window/splitwin.cxx b/vcl/source/window/splitwin.cxx
index 572a9a4b6966..e6d62d305580 100644
--- a/vcl/source/window/splitwin.cxx
+++ b/vcl/source/window/splitwin.cxx
@@ -111,7 +111,7 @@ ImplSplitItem::ImplSplitItem()
     , mnOldSplitSize(0)
     , mnOldWidth(0)
     , mnOldHeight(0)
-    , mpSet(0)
+    , mpSet(nullptr)
     , mnId(0)
     , mnBits(SplitWindowItemFlags::NONE)
     , mbFixed(false)
@@ -130,15 +130,15 @@ void ImplSplitItem::dispose()
 {
     if (mpSet) {
         delete mpSet ;
-        mpSet = NULL;
+        mpSet = nullptr;
     }
     mpWindow.clear();
     mpOrgParent.clear();
 }
 
 ImplSplitSet::ImplSplitSet() :
-    mpWallpaper( NULL ),
-    mpBitmap( NULL ),
+    mpWallpaper( nullptr ),
+    mpBitmap( nullptr ),
     mnLastSize( 0 ),
     mnSplitSize( SPLITWIN_SPLITSIZE ),
     mnId( 0 ),
@@ -161,12 +161,12 @@ void ImplSplitSet::dispose()
 
     if ( mpWallpaper ) {
         delete mpWallpaper;
-        mpWallpaper = NULL;
+        mpWallpaper = nullptr;
 }
 
     if ( mpBitmap ) {
         delete mpBitmap;
-        mpBitmap = NULL;
+        mpBitmap = nullptr;
     }
 }
 
@@ -359,7 +359,7 @@ static ImplSplitSet* ImplFindSet( ImplSplitSet* pSet, sal_uInt16 nId )
         }
     }
 
-    return NULL;
+    return nullptr;
 }
 
 static ImplSplitSet* ImplFindItem( ImplSplitSet* pSet, sal_uInt16 nId, sal_uInt16& rPos )
@@ -387,7 +387,7 @@ static ImplSplitSet* ImplFindItem( ImplSplitSet* pSet, sal_uInt16 nId, sal_uInt1
         }
     }
 
-    return NULL;
+    return nullptr;
 }
 
 static sal_uInt16 ImplFindItem( ImplSplitSet* pSet, vcl::Window* pWindow )
@@ -1304,8 +1304,8 @@ void SplitWindow::ImplInit( vcl::Window* pParent, WinBits nStyle )
 
     mpMainSet               = pNewSet;
     mpBaseSet               = pNewSet;
-    mpSplitSet              = NULL;
-    mpLastSizes             = NULL;
+    mpSplitSet              = nullptr;
+    mpLastSizes             = nullptr;
     mnDX                    = 0;
     mnDY                    = 0;
     mnLeftBorder            = 0;
@@ -1404,7 +1404,7 @@ void SplitWindow::dispose()
     // delete Sets
     if (mpMainSet) {
         delete mpMainSet ;
-        mpMainSet = NULL; //NULL for base-class callbacks during destruction
+        mpMainSet = nullptr; //NULL for base-class callbacks during destruction
     }
     DockingWindow::dispose();
 }
@@ -2487,8 +2487,8 @@ void SplitWindow::Tracking( const TrackingEvent& rTEvt )
         if ( rTEvt.IsTrackingEnded() )
         {
             delete [] mpLastSizes;
-            mpLastSizes     = NULL;
-            mpSplitSet      = NULL;
+            mpLastSizes     = nullptr;
+            mpSplitSet      = nullptr;
             mnMouseOff      = 0;
             mnMStartPos     = 0;
             mnMSplitPos     = 0;
@@ -2501,9 +2501,9 @@ void SplitWindow::Tracking( const TrackingEvent& rTEvt )
 
 bool SplitWindow::PreNotify( NotifyEvent& rNEvt )
 {
-    const MouseEvent* pMouseEvt = NULL;
+    const MouseEvent* pMouseEvt = nullptr;
 
-    if( (rNEvt.GetType() == MouseNotifyEvent::MOUSEMOVE) && (pMouseEvt = rNEvt.GetMouseEvent()) != NULL )
+    if( (rNEvt.GetType() == MouseNotifyEvent::MOUSEMOVE) && (pMouseEvt = rNEvt.GetMouseEvent()) != nullptr )
     {
         if( !pMouseEvt->GetButtons() && !pMouseEvt->IsSynthetic() && !pMouseEvt->IsModifierChanged() )
         {
@@ -2719,7 +2719,7 @@ void SplitWindow::InsertItem( sal_uInt16 nId, long nSize,
                               sal_uInt16 nPos, sal_uInt16 nIntoSetId,
                               SplitWindowItemFlags nBits )
 {
-    InsertItem( nId, NULL, nSize, nPos, nIntoSetId, nBits );
+    InsertItem( nId, nullptr, nSize, nPos, nIntoSetId, nBits );
 }
 
 void SplitWindow::RemoveItem( sal_uInt16 nId, bool bHide )
@@ -2743,7 +2743,7 @@ void SplitWindow::RemoveItem( sal_uInt16 nId, bool bHide )
     // delete set if required
     if ( !pWindow ) {
         delete pItem->mpSet ;
-        pItem->mpSet = NULL;
+        pItem->mpSet = nullptr;
     }
 
     // remove item
@@ -3100,7 +3100,7 @@ void SplitWindow::SetItemSizeRange (sal_uInt16 nId, const Range& rRange)
     sal_uInt16 nPos;
     ImplSplitSet* pSet = ImplFindItem(mpBaseSet, nId, nPos);
 
-    if (pSet != NULL)
+    if (pSet != nullptr)
     {
         pSet->mpItems[nPos]->mnMinSize = rRange.Min();
         pSet->mpItems[nPos]->mnMaxSize = rRange.Max();
@@ -3121,7 +3121,7 @@ sal_uInt16 SplitWindow::GetSet( sal_uInt16 nId ) const
 bool SplitWindow::IsItemValid( sal_uInt16 nId ) const
 {
     sal_uInt16          nPos;
-    ImplSplitSet* pSet = mpBaseSet ? ImplFindItem(mpBaseSet, nId, nPos) : NULL;
+    ImplSplitSet* pSet = mpBaseSet ? ImplFindItem(mpBaseSet, nId, nPos) : nullptr;
 
     if ( pSet )
         return true;
diff --git a/vcl/source/window/stacking.cxx b/vcl/source/window/stacking.cxx
index 3a3e8730565f..cb5f316b94aa 100644
--- a/vcl/source/window/stacking.cxx
+++ b/vcl/source/window/stacking.cxx
@@ -148,8 +148,8 @@ void Window::ImplRemoveWindow( bool bRemoveFrameData )
                 mpWindowImpl->mpParent->mpWindowImpl->mpLastChild = mpWindowImpl->mpPrev;
         }
 
-        mpWindowImpl->mpPrev = NULL;
-        mpWindowImpl->mpNext = NULL;
+        mpWindowImpl->mpPrev = nullptr;
+        mpWindowImpl->mpNext = nullptr;
     }
 
     if ( bRemoveFrameData )
@@ -205,7 +205,7 @@ void Window::ImplToBottomChild()
         mpWindowImpl->mpPrev = mpWindowImpl->mpParent->mpWindowImpl->mpLastChild;
         mpWindowImpl->mpParent->mpWindowImpl->mpLastChild = this;
         mpWindowImpl->mpPrev->mpWindowImpl->mpNext = this;
-        mpWindowImpl->mpNext = NULL;
+        mpWindowImpl->mpNext = nullptr;
     }
 }
 
@@ -228,7 +228,7 @@ void Window::ImplCalcToTop( ImplCalcToTopData* pPrevData )
             {
                 ImplCalcToTopData* pData    = new ImplCalcToTopData;
                 pPrevData->mpNext           = pData;
-                pData->mpNext               = NULL;
+                pData->mpNext               = nullptr;
                 pData->mpWindow             = this;
                 pData->mpInvalidateRegion   = new vcl::Region( aInvalidateRegion );
             }
@@ -339,7 +339,7 @@ void Window::ImplStartToTop( ToTopFlags nFlags )
 
     // first calculate paint areas
     vcl::Window* pTempOverlapWindow = pOverlapWindow;
-    aStartData.mpNext = NULL;
+    aStartData.mpNext = nullptr;
     pCurData = &aStartData;
     do
     {
@@ -577,7 +577,7 @@ void Window::SetZOrder( vcl::Window* pRefWindow, ZOrderFlags nFlags )
                 // Invalidate all windows which are next to each other
                 // Is INCOMPLETE !!!
                 Rectangle   aWinRect( Point( mnOutOffX, mnOutOffY ), Size( mnOutWidth, mnOutHeight ) );
-                vcl::Window*     pWindow = NULL;
+                vcl::Window*     pWindow = nullptr;
                 if ( ImplIsOverlapWindow() )
                 {
                     if ( mpWindowImpl->mpOverlapWindow )
@@ -676,7 +676,7 @@ vcl::Window* Window::ImplFindWindow( const Point& rFramePos )
 
     // then we check our window
     if ( !mpWindowImpl->mbVisible )
-        return NULL;
+        return nullptr;
 
     sal_uInt16 nHitTest = ImplHitTest( rFramePos );
     if ( nHitTest & WINDOW_HITTEST_INSIDE )
@@ -692,12 +692,12 @@ vcl::Window* Window::ImplFindWindow( const Point& rFramePos )
         }
 
         if ( nHitTest & WINDOW_HITTEST_TRANSPARENT )
-            return NULL;
+            return nullptr;
         else
             return this;
     }
 
-    return NULL;
+    return nullptr;
 }
 
 bool Window::ImplIsRealParentPath( const vcl::Window* pWindow ) const
@@ -844,7 +844,7 @@ SystemWindow* Window::GetSystemWindow() const
 static SystemWindow *ImplGetLastSystemWindow( vcl::Window *pWin )
 {
     // get the most top-level system window, the one that contains the taskpanelist
-    SystemWindow *pSysWin = NULL;
+    SystemWindow *pSysWin = nullptr;
     if( !pWin )
         return pSysWin;
     vcl::Window *pMyParent = pWin;
@@ -867,7 +867,7 @@ void Window::SetParent( vcl::Window* pNewParent )
 
     // check if the taskpanelist would change and move the window pointer accordingly
     SystemWindow *pSysWin = ImplGetLastSystemWindow(this);
-    SystemWindow *pNewSysWin = NULL;
+    SystemWindow *pNewSysWin = nullptr;
     bool bChangeTaskPaneList = false;
     if( pSysWin && pSysWin->ImplIsInTaskPaneList( this ) )
     {
@@ -907,16 +907,16 @@ void Window::SetParent( vcl::Window* pNewParent )
 
     // check if the overlap window changes
     vcl::Window* pOldOverlapWindow;
-    vcl::Window* pNewOverlapWindow = NULL;
+    vcl::Window* pNewOverlapWindow = nullptr;
     if ( ImplIsOverlapWindow() )
-        pOldOverlapWindow = NULL;
+        pOldOverlapWindow = nullptr;
     else
     {
         pNewOverlapWindow = pNewParent->ImplGetFirstOverlapWindow();
         if ( mpWindowImpl->mpOverlapWindow.get() != pNewOverlapWindow )
             pOldOverlapWindow = mpWindowImpl->mpOverlapWindow;
         else
-            pOldOverlapWindow = NULL;
+            pOldOverlapWindow = nullptr;
     }
 
     // convert windows in the hierarchy
@@ -928,17 +928,17 @@ void Window::SetParent( vcl::Window* pNewParent )
         if ( mpWindowImpl->mpFrameData->mpFocusWin )
         {
             if ( IsWindowOrChild( mpWindowImpl->mpFrameData->mpFocusWin ) )
-                mpWindowImpl->mpFrameData->mpFocusWin = NULL;
+                mpWindowImpl->mpFrameData->mpFocusWin = nullptr;
         }
         if ( mpWindowImpl->mpFrameData->mpMouseMoveWin )
         {
             if ( IsWindowOrChild( mpWindowImpl->mpFrameData->mpMouseMoveWin ) )
-                mpWindowImpl->mpFrameData->mpMouseMoveWin = NULL;
+                mpWindowImpl->mpFrameData->mpMouseMoveWin = nullptr;
         }
         if ( mpWindowImpl->mpFrameData->mpMouseDownWin )
         {
             if ( IsWindowOrChild( mpWindowImpl->mpFrameData->mpMouseDownWin ) )
-                mpWindowImpl->mpFrameData->mpMouseDownWin = NULL;
+                mpWindowImpl->mpFrameData->mpMouseDownWin = nullptr;
         }
     }
     ImplRemoveWindow( bNewFrame );
@@ -971,7 +971,7 @@ void Window::SetParent( vcl::Window* pNewParent )
         if ( bFocusWin ||
              (pOldOverlapWindow->mpWindowImpl->mpLastFocusWindow &&
               IsWindowOrChild( pOldOverlapWindow->mpWindowImpl->mpLastFocusWindow )) )
-            pOldOverlapWindow->mpWindowImpl->mpLastFocusWindow = NULL;
+            pOldOverlapWindow->mpWindowImpl->mpLastFocusWindow = nullptr;
 
         vcl::Window* pOverlapWindow = pOldOverlapWindow->mpWindowImpl->mpFirstOverlap;
         while ( pOverlapWindow )
@@ -1041,7 +1041,7 @@ sal_uInt16 Window::GetChildCount() const
 vcl::Window* Window::GetChild( sal_uInt16 nChild ) const
 {
     if (!mpWindowImpl)
-        return NULL;
+        return nullptr;
 
     sal_uInt16  nChildCount = 0;
     vcl::Window* pChild = mpWindowImpl->mpFirstChild;
@@ -1053,13 +1053,13 @@ vcl::Window* Window::GetChild( sal_uInt16 nChild ) const
         nChildCount++;
     }
 
-    return NULL;
+    return nullptr;
 }
 
 vcl::Window* Window::GetWindow( GetWindowType nType ) const
 {
     if (!mpWindowImpl)
-        return 0;
+        return nullptr;
 
     switch ( nType )
     {
@@ -1111,40 +1111,40 @@ vcl::Window* Window::GetWindow( GetWindowType nType ) const
             return const_cast<vcl::Window*>(this);
 
         case GetWindowType::FirstTopWindowChild:
-            return ImplGetWinData()->maTopWindowChildren.empty() ? NULL : (*ImplGetWinData()->maTopWindowChildren.begin()).get();
+            return ImplGetWinData()->maTopWindowChildren.empty() ? nullptr : (*ImplGetWinData()->maTopWindowChildren.begin()).get();
 
         case GetWindowType::LastTopWindowChild:
-            return ImplGetWinData()->maTopWindowChildren.empty() ? NULL : (*ImplGetWinData()->maTopWindowChildren.rbegin()).get();
+            return ImplGetWinData()->maTopWindowChildren.empty() ? nullptr : (*ImplGetWinData()->maTopWindowChildren.rbegin()).get();
 
         case GetWindowType::PrevTopWindowSibling:
         {
             if ( !mpWindowImpl->mpRealParent )
-                return NULL;
+                return nullptr;
             const ::std::list< VclPtr<vcl::Window> >& rTopWindows( mpWindowImpl->mpRealParent->ImplGetWinData()->maTopWindowChildren );
             ::std::list< VclPtr<vcl::Window> >::const_iterator myPos =
                 ::std::find( rTopWindows.begin(), rTopWindows.end(), this );
             if ( myPos == rTopWindows.end() )
-                return NULL;
+                return nullptr;
             if ( myPos == rTopWindows.begin() )
-                return NULL;
+                return nullptr;
             return *--myPos;
         }
 
         case GetWindowType::NextTopWindowSibling:
         {
             if ( !mpWindowImpl->mpRealParent )
-                return NULL;
+                return nullptr;
             const ::std::list< VclPtr<vcl::Window> >& rTopWindows( mpWindowImpl->mpRealParent->ImplGetWinData()->maTopWindowChildren );
             ::std::list< VclPtr<vcl::Window> >::const_iterator myPos =
                 ::std::find( rTopWindows.begin(), rTopWindows.end(), this );
             if ( ( myPos == rTopWindows.end() ) || ( ++myPos == rTopWindows.end() ) )
-                return NULL;
+                return nullptr;
             return *myPos;
         }
 
     }
 
-    return NULL;
+    return nullptr;
 }
 
 bool Window::IsChild( const vcl::Window* pWindow, bool bSystemWindow ) const
@@ -1183,7 +1183,7 @@ void Window::ImplSetFrameParent( const vcl::Window* pParent )
         {
             DBG_ASSERT( mpWindowImpl->mpFrame != pFrameWindow->mpWindowImpl->mpFrame, "SetFrameParent to own" );
             DBG_ASSERT( mpWindowImpl->mpFrame, "no frame" );
-            SalFrame* pParentFrame = pParent ? pParent->mpWindowImpl->mpFrame : NULL;
+            SalFrame* pParentFrame = pParent ? pParent->mpWindowImpl->mpFrame : nullptr;
             pFrameWindow->mpWindowImpl->mpFrame->SetParent( pParentFrame );
         }
         pFrameWindow = pFrameWindow->mpWindowImpl->mpFrameData->mpNextFrame;
diff --git a/vcl/source/window/status.cxx b/vcl/source/window/status.cxx
index c4a349012faf..c9649aaa8e77 100644
--- a/vcl/source/window/status.cxx
+++ b/vcl/source/window/status.cxx
@@ -53,7 +53,7 @@ public:
 
 StatusBar::ImplData::ImplData()
 {
-    mpVirDev = NULL;
+    mpVirDev = nullptr;
     mbDrawItemFrames = false;
     mnItemBorderWidth = 0;
 }
@@ -120,7 +120,7 @@ void StatusBar::ImplInit( vcl::Window* pParent, WinBits nStyle )
     if ( !(nStyle & (WB_LEFT | WB_RIGHT)) )
         nStyle |= WB_RIGHT;
 
-    Window::ImplInit( pParent, nStyle & ~WB_BORDER, NULL );
+    Window::ImplInit( pParent, nStyle & ~WB_BORDER, nullptr );
 
     // remember WinBits
     mpItemList      = new ImplStatusItemList;
@@ -300,7 +300,7 @@ Rectangle StatusBar::ImplGetItemRectPos( sal_uInt16 nPos ) const
 {
     Rectangle       aRect;
     ImplStatusItem* pItem;
-    pItem = ( nPos < mpItemList->size() ) ? (*mpItemList)[ nPos ] : NULL;
+    pItem = ( nPos < mpItemList->size() ) ? (*mpItemList)[ nPos ] : nullptr;
     if ( pItem )
     {
         if ( pItem->mbVisible )
@@ -940,7 +940,7 @@ void StatusBar::InsertItem( sal_uInt16 nItemId, sal_uLong nWidth,
     pItem->mnBits           = nBits;
     pItem->mnWidth          = (long)nWidth+nFudge+STATUSBAR_OFFSET;
     pItem->mnOffset         = nOffset;
-    pItem->mpUserData       = 0;
+    pItem->mpUserData       = nullptr;
     pItem->mbVisible        = true;
 
     // add item to list
@@ -1255,7 +1255,7 @@ void* StatusBar::GetItemData( sal_uInt16 nItemId ) const
     if ( nPos != STATUSBAR_ITEM_NOTFOUND )
         return (*mpItemList)[ nPos ]->mpUserData;
 
-    return NULL;
+    return nullptr;
 }
 
 void StatusBar::RedrawItem(sal_uInt16 nItemId)
diff --git a/vcl/source/window/syschild.cxx b/vcl/source/window/syschild.cxx
index 0f16a49d717f..0615cf5f69e1 100644
--- a/vcl/source/window/syschild.cxx
+++ b/vcl/source/window/syschild.cxx
@@ -82,7 +82,7 @@ long ImplSysChildProc( void* pInst, SalObject* /* pObject */,
             if ( !pWindow->ImplGetFrameData()->mnFocusId )
             {
                 pWindow->ImplGetFrameData()->mbStartFocusState = true;
-                pWindow->ImplGetFrameData()->mnFocusId = Application::PostUserEvent( LINK( pWindow->ImplGetFrameWindow(), vcl::Window, ImplAsyncFocusHdl ), NULL, true );
+                pWindow->ImplGetFrameData()->mnFocusId = Application::PostUserEvent( LINK( pWindow->ImplGetFrameWindow(), vcl::Window, ImplAsyncFocusHdl ), nullptr, true );
             }
             break;
 
@@ -108,7 +108,7 @@ void SystemChildWindow::ImplInitSysChild( vcl::Window* pParent, WinBits nStyle,
 {
     mpWindowImpl->mpSysObj = ImplGetSVData()->mpDefInst->CreateObject( pParent->ImplGetFrame(), pData, bShow );
 
-    Window::ImplInit( pParent, nStyle, NULL );
+    Window::ImplInit( pParent, nStyle, nullptr );
 
     // we do not paint if it is the right SysChild
     if ( GetSystemData() )
@@ -122,7 +122,7 @@ void SystemChildWindow::ImplInitSysChild( vcl::Window* pParent, WinBits nStyle,
 SystemChildWindow::SystemChildWindow( vcl::Window* pParent, WinBits nStyle ) :
     Window( WINDOW_SYSTEMCHILDWINDOW )
 {
-    ImplInitSysChild( pParent, nStyle, NULL );
+    ImplInitSysChild( pParent, nStyle, nullptr );
 }
 
 SystemChildWindow::SystemChildWindow( vcl::Window* pParent, WinBits nStyle, SystemWindowData *pData, bool bShow ) :
@@ -142,7 +142,7 @@ void SystemChildWindow::dispose()
     if ( mpWindowImpl && mpWindowImpl->mpSysObj )
     {
         ImplGetSVData()->mpDefInst->DestroyObject( mpWindowImpl->mpSysObj );
-        mpWindowImpl->mpSysObj = NULL;
+        mpWindowImpl->mpSysObj = nullptr;
     }
     Window::dispose();
 }
@@ -152,7 +152,7 @@ const SystemEnvData* SystemChildWindow::GetSystemData() const
     if ( mpWindowImpl->mpSysObj )
         return mpWindowImpl->mpSysObj->GetSystemData();
     else
-        return NULL;
+        return nullptr;
 }
 
 void SystemChildWindow::EnableEraseBackground( bool bEnable )
@@ -181,7 +181,7 @@ void SystemChildWindow::ImplTestJavaException( void* pEnv )
 
         if(jsMessage)
         {
-            const jchar * jcMessage = pJavaEnv->GetStringChars(jsMessage, NULL);
+            const jchar * jcMessage = pJavaEnv->GetStringChars(jsMessage, nullptr);
             ouMessage = OUString(jcMessage);
             pJavaEnv->ReleaseStringChars(jsMessage, jcMessage);
         }
@@ -234,7 +234,7 @@ sal_IntPtr SystemChildWindow::GetParentWindowHandle( bool bUseJava )
                     rtl_getGlobalProcessId( reinterpret_cast<sal_uInt8*>(aProcessID.getArray()) );
                     aProcessID[ 16 ] = 0;
                     OSL_ENSURE(sizeof (sal_Int64) >= sizeof (jvmaccess::VirtualMachine *), "Pointer cannot be represented as sal_Int64");
-                    sal_Int64 nPointer = reinterpret_cast< sal_Int64 >( static_cast< jvmaccess::VirtualMachine * >(0));
+                    sal_Int64 nPointer = reinterpret_cast< sal_Int64 >( static_cast< jvmaccess::VirtualMachine * >(nullptr));
                     xJavaVM->getJavaVM(aProcessID) >>= nPointer;
                     xVM = reinterpret_cast< jvmaccess::VirtualMachine * >(nPointer);
 
diff --git a/vcl/source/window/syswin.cxx b/vcl/source/window/syswin.cxx
index a8f753800f0c..d353f4607d7d 100644
--- a/vcl/source/window/syswin.cxx
+++ b/vcl/source/window/syswin.cxx
@@ -58,7 +58,7 @@ public:
 
 SystemWindow::ImplData::ImplData()
 {
-    mpTaskPaneList = NULL;
+    mpTaskPaneList = nullptr;
     maMaxOutSize = Size( SHRT_MAX, SHRT_MAX );
 }
 
@@ -73,7 +73,7 @@ void SystemWindow::Init()
     mpWindowImpl->mbSysWin            = true;
     mpWindowImpl->mnActivateMode      = ActivateModeFlags::GrabFocus;
 
-    mpMenuBar           = NULL;
+    mpMenuBar           = nullptr;
     mbPinned            = false;
     mbRollUp            = false;
     mbRollFunc          = false;
@@ -84,7 +84,7 @@ void SystemWindow::Init()
     mbInitialLayoutDone = false;
     mnMenuBarMode       = MenuBarMode::Normal;
     mnIcon              = 0;
-    mpDialogParent      = NULL;
+    mpDialogParent      = nullptr;
 
     //To-Do, reuse maResizeTimer
     maLayoutIdle.SetPriority(SchedulerPriority::RESIZE);
@@ -115,7 +115,7 @@ void SystemWindow::dispose()
 {
     maLayoutIdle.Stop();
     delete mpImplData;
-    mpImplData = NULL;
+    mpImplData = nullptr;
 
     // Hack to make sure code called from base ~Window does not interpret this
     // as a SystemWindow (which it no longer is by then):
@@ -198,7 +198,7 @@ bool SystemWindow::PreNotify( NotifyEvent& rNEvt )
 TaskPaneList* SystemWindow::GetTaskPaneList()
 {
     if( !mpImplData )
-        return NULL;
+        return nullptr;
     if( mpImplData->mpTaskPaneList )
         return mpImplData->mpTaskPaneList ;
     else
@@ -909,8 +909,8 @@ void SystemWindow::SetMenuBar(MenuBar* pMenuBar)
     if ( mpMenuBar != pMenuBar )
     {
         MenuBar* pOldMenuBar = mpMenuBar;
-        vcl::Window*  pOldWindow = NULL;
-        vcl::Window*  pNewWindow=NULL;
+        vcl::Window*  pOldWindow = nullptr;
+        vcl::Window*  pNewWindow=nullptr;
         mpMenuBar = pMenuBar;
 
         if ( mpWindowImpl->mpBorderWindow && (mpWindowImpl->mpBorderWindow->GetType() == WINDOW_BORDERWINDOW) )
@@ -918,7 +918,7 @@ void SystemWindow::SetMenuBar(MenuBar* pMenuBar)
             if ( pOldMenuBar )
                 pOldWindow = pOldMenuBar->ImplGetWindow();
             else
-                pOldWindow = NULL;
+                pOldWindow = nullptr;
             if ( pOldWindow )
             {
                 CallEventListeners( VCLEVENT_WINDOW_MENUBARREMOVED, static_cast<void*>(pOldMenuBar) );
@@ -934,11 +934,11 @@ void SystemWindow::SetMenuBar(MenuBar* pMenuBar)
                 CallEventListeners( VCLEVENT_WINDOW_MENUBARADDED, static_cast<void*>(pMenuBar) );
             }
             else
-                static_cast<ImplBorderWindow*>(mpWindowImpl->mpBorderWindow.get())->SetMenuBarWindow( NULL );
+                static_cast<ImplBorderWindow*>(mpWindowImpl->mpBorderWindow.get())->SetMenuBarWindow( nullptr );
             ImplToBottomChild();
             if ( pOldMenuBar )
             {
-                bool bDelete = (pMenuBar == 0);
+                bool bDelete = (pMenuBar == nullptr);
                 if( bDelete && pOldWindow )
                 {
                     if( mpImplData->mpTaskPaneList )
@@ -946,7 +946,7 @@ void SystemWindow::SetMenuBar(MenuBar* pMenuBar)
                 }
                 MenuBar::ImplDestroy( pOldMenuBar, bDelete );
                 if( bDelete )
-                    pOldWindow = NULL;  // will be deleted in MenuBar::ImplDestroy,
+                    pOldWindow = nullptr;  // will be deleted in MenuBar::ImplDestroy,
             }
 
         }
diff --git a/vcl/source/window/tabdlg.cxx b/vcl/source/window/tabdlg.cxx
index c5bea40f1278..3e8531b43cc2 100644
--- a/vcl/source/window/tabdlg.cxx
+++ b/vcl/source/window/tabdlg.cxx
@@ -25,8 +25,8 @@
 
 void TabDialog::ImplInitTabDialogData()
 {
-    mpFixedLine     = NULL;
-    mpViewWindow    = NULL;
+    mpFixedLine     = nullptr;
+    mpViewWindow    = nullptr;
     meViewAlign     = WindowAlign::Left;
     mbPosControls   = true;
 }
@@ -39,7 +39,7 @@ void TabDialog::ImplPosControls()
     Size        aCtrlSize( IMPL_MINSIZE_BUTTON_WIDTH, IMPL_MINSIZE_BUTTON_HEIGHT );
     long        nDownCtrl = 0;
     long        nOffY = 0;
-    vcl::Window*     pTabControl = NULL;
+    vcl::Window*     pTabControl = nullptr;
 
     vcl::Window* pChild = GetWindow( GetWindowType::FirstChild );
     while ( pChild )
diff --git a/vcl/source/window/tabpage.cxx b/vcl/source/window/tabpage.cxx
index e5c4c6c4d9f2..e22f91d9402c 100644
--- a/vcl/source/window/tabpage.cxx
+++ b/vcl/source/window/tabpage.cxx
@@ -36,7 +36,7 @@ void TabPage::ImplInit( vcl::Window* pParent, WinBits nStyle )
     if ( !(nStyle & WB_NODIALOGCONTROL) )
         nStyle |= WB_DIALOGCONTROL;
 
-    Window::ImplInit( pParent, nStyle, NULL );
+    Window::ImplInit( pParent, nStyle, nullptr );
 
     ImplInitSettings();
 
diff --git a/vcl/source/window/taskpanelist.cxx b/vcl/source/window/taskpanelist.cxx
index 081947c538e3..e12f8d4ba418 100644
--- a/vcl/source/window/taskpanelist.cxx
+++ b/vcl/source/window/taskpanelist.cxx
@@ -180,7 +180,7 @@ bool TaskPaneList::HandleKeyEvent(const KeyEvent& rKeyEvent)
                 }
 
                 // activate next task pane
-                vcl::Window *pNextWin = NULL;
+                vcl::Window *pNextWin = nullptr;
 
                 if( bSplitterOnly )
                     pNextWin = FindNextSplitter( *p );
@@ -213,9 +213,9 @@ bool TaskPaneList::HandleKeyEvent(const KeyEvent& rKeyEvent)
         // the focus is not in the list: activate first float if F6 was pressed
         vcl::Window *pWin;
         if( bSplitterOnly )
-            pWin = FindNextSplitter( NULL );
+            pWin = FindNextSplitter( nullptr );
         else
-            pWin = FindNextFloat( NULL, bForward );
+            pWin = FindNextFloat( nullptr, bForward );
         if( pWin )
         {
             ImplTaskPaneListGrabFocus( pWin, bForward );
diff --git a/vcl/source/window/toolbox.cxx b/vcl/source/window/toolbox.cxx
index cfcf37e8849b..3f414c759056 100644
--- a/vcl/source/window/toolbox.cxx
+++ b/vcl/source/window/toolbox.cxx
@@ -124,7 +124,7 @@ public:
     void            StartDragging( ToolBox* pDragBox,
                                    const Point& rPos, const Rectangle& rRect,
                                    sal_uInt16 nLineMode, bool bResizeItem,
-                                   void* pData = NULL );
+                                   void* pData = nullptr );
     void            Dragging( const Point& rPos );
     void            EndDragging( bool bOK = true );
     void            HideDragRect() { if ( mbShowDragRect ) mpDragBox->HideTracking(); }
@@ -658,7 +658,7 @@ const ImplToolItem *ToolBox::ImplGetFirstClippedItem( const ToolBox* pThis )
             return &(*it);
         ++it;
     }
-    return NULL;
+    return nullptr;
 }
 
 Size ToolBox::ImplCalcSize( const ToolBox* pThis, sal_uInt16 nCalcLines, sal_uInt16 nCalcMode )
@@ -1128,12 +1128,12 @@ sal_uInt16 ToolBox::ImplFindItemPos( ToolBox* pBox, const Point& rPos )
 
 ImplTBDragMgr::ImplTBDragMgr()
     : mpBoxList(new ImplTBList())
-    , mpDragBox(NULL)
+    , mpDragBox(nullptr)
     , mnMinWidth(0)
     , mnMaxWidth(0)
     , mnLineMode(0)
     , mnStartLines(0)
-    , mpCustomizeData(NULL)
+    , mpCustomizeData(nullptr)
     , mbResizeMode(false)
     , mbShowDragRect(false)
 {
@@ -1173,7 +1173,7 @@ ToolBox* ImplTBDragMgr::FindToolBox( const Rectangle& rRect )
         }
     }
 
-    return NULL;
+    return nullptr;
 }
 
 void ImplTBDragMgr::StartDragging( ToolBox* pToolBox,
@@ -1319,12 +1319,12 @@ void ImplTBDragMgr::EndDragging( bool bOK )
                 }
             }
         }
-        mpCustomizeData = NULL;
+        mpCustomizeData = nullptr;
         mbResizeMode = false;
         mpDragBox->Deactivate();
     }
 
-    mpDragBox = NULL;
+    mpDragBox = nullptr;
 }
 
 void ImplTBDragMgr::UpdateDragRect()
@@ -1349,7 +1349,7 @@ void ToolBox::ImplInit( vcl::Window* pParent, WinBits nStyle )
     // initialize variables
     ImplGetWindowImpl()->mbToolBox         = true;
     mpData                = new ImplToolBoxPrivateData;
-    mpFloatWin        = NULL;
+    mpFloatWin        = nullptr;
     mnDX              = 0;
     mnDY              = 0;
     mnMaxItemWidth    = 0;
@@ -1642,11 +1642,11 @@ void ToolBox::dispose()
     // still connected
     if ( mpFloatWin )
         mpFloatWin->EndPopupMode( FloatWinPopupEndFlags::Cancel );
-    mpFloatWin = NULL;
+    mpFloatWin = nullptr;
 
     // delete private data
     delete mpData;
-    mpData = NULL;
+    mpData = nullptr;
 
     // remove the lists when there are no more toolbox references to
     // the lists
@@ -1660,7 +1660,7 @@ void ToolBox::dispose()
         if ( !pSVData->maCtrlData.mpTBDragMgr->size() )
         {
             delete pSVData->maCtrlData.mpTBDragMgr;
-            pSVData->maCtrlData.mpTBDragMgr = NULL;
+            pSVData->maCtrlData.mpTBDragMgr = nullptr;
         }
     }
     mpFloatWin.clear();
@@ -1670,7 +1670,7 @@ void ToolBox::dispose()
 ImplToolItem* ToolBox::ImplGetItem( sal_uInt16 nItemId ) const
 {
     if (!mpData)
-        return NULL;
+        return nullptr;
 
     std::vector< ImplToolItem >::iterator it = mpData->m_aItems.begin();
     while ( it != mpData->m_aItems.end() )
@@ -1680,7 +1680,7 @@ ImplToolItem* ToolBox::ImplGetItem( sal_uInt16 nItemId ) const
         ++it;
     }
 
-    return NULL;
+    return nullptr;
 }
 
 static void ImplAddButtonBorder( long &rWidth, long& rHeight, bool bNativeButtons )
@@ -2399,7 +2399,7 @@ void ToolBox::ImplFormat( bool bResize )
 
             // compute line breaks and visible lines give the current window width (nMax)
             // the break indicators will be stored within each item (it->mbBreak)
-            mnCurLines = ImplCalcBreaks( nMax, NULL, mbHorz );
+            mnCurLines = ImplCalcBreaks( nMax, nullptr, mbHorz );
 
             // check for scrollbar buttons or dropdown menu
             // (if a menu is enabled, this will be used to store clipped
@@ -2411,7 +2411,7 @@ void ToolBox::ImplFormat( bool bResize )
                 if( !IsMenuEnabled() )
                 {
                     nMax -= TB_SPIN_SIZE+TB_SPIN_OFFSET;
-                    mnCurLines = ImplCalcBreaks( nMax, NULL, mbHorz );
+                    mnCurLines = ImplCalcBreaks( nMax, nullptr, mbHorz );
                 }
 
                 // compute scroll rectangles or menu button
@@ -2972,7 +2972,7 @@ void ToolBox::ImplDrawButton(vcl::RenderContext& rRenderContext, const Rectangle
     }
 
     if (!bNativeOk)
-        vcl::RenderTools::DrawSelectionBackground(rRenderContext, *this, rRect, bIsWindow ? 3 : highlight, bChecked, true, bIsWindow, NULL, 2);
+        vcl::RenderTools::DrawSelectionBackground(rRenderContext, *this, rRect, bIsWindow ? 3 : highlight, bChecked, true, bIsWindow, nullptr, 2);
 }
 
 void ToolBox::ImplDrawItem(vcl::RenderContext& rRenderContext, sal_uInt16 nPos, sal_uInt16 nHighlight, bool bPaint, bool bLayout)
@@ -2988,8 +2988,8 @@ void ToolBox::ImplDrawItem(vcl::RenderContext& rRenderContext, sal_uInt16 nPos,
     rRenderContext.SetFillColor();
 
     ImplToolItem* pItem = &mpData->m_aItems[nPos];
-    MetricVector* pVector = bLayout ? &mpData->m_pLayoutData->m_aUnicodeBoundRects : NULL;
-    OUString* pDisplayText = bLayout ? &mpData->m_pLayoutData->m_aDisplayText : NULL;
+    MetricVector* pVector = bLayout ? &mpData->m_pLayoutData->m_aUnicodeBoundRects : nullptr;
+    OUString* pDisplayText = bLayout ? &mpData->m_pLayoutData->m_aDisplayText : nullptr;
 
     if (!pItem->mbEnabled)
         nHighlight = 0;
@@ -3057,7 +3057,7 @@ void ToolBox::ImplDrawItem(vcl::RenderContext& rRenderContext, sal_uInt16 nPos,
         pMgr->HideDragRect();
     }
     else
-        pMgr = NULL;
+        pMgr = nullptr;
 
     // during configuration mode visible windows will be drawn in a special way
     if ( mbCustomizeMode && pItem->mbShowWindow )
@@ -3346,7 +3346,7 @@ void ToolBox::ImplFloatControl( bool bStart, FloatingWindow* pFloatWindow )
     }
     else
     {
-        mpFloatWin = NULL;
+        mpFloatWin = nullptr;
 
         // if focus is still in this toolbox, then the floater was opened by keyboard
         // draw current item with highlight and keep old state
@@ -4953,7 +4953,7 @@ void ToolBox::GetFocus()
 
 void ToolBox::LoseFocus()
 {
-    ImplChangeHighlight( NULL, true );
+    ImplChangeHighlight( nullptr, true );
 
     DockingWindow::LoseFocus();
 }
@@ -5069,7 +5069,7 @@ bool ToolBox::ImplOpenItem( vcl::KeyCode aKeyCode )
             return bRet;
 
         UpdateCustomMenu();
-        mpData->mnEventId = Application::PostUserEvent( LINK( this, ToolBox, ImplCallExecuteCustomMenu ), NULL, true );
+        mpData->mnEventId = Application::PostUserEvent( LINK( this, ToolBox, ImplCallExecuteCustomMenu ), nullptr, true );
     }
     else if( mnHighItemId &&  ImplGetItem( mnHighItemId ) &&
         (ImplGetItem( mnHighItemId )->mnBits & ToolBoxItemBits::DROPDOWN) )
@@ -5186,13 +5186,13 @@ void ToolBox::KeyInput( const KeyEvent& rKEvt )
         break;
         case KEY_END:
             {
-                ImplChangeHighlight( NULL );
+                ImplChangeHighlight( nullptr );
                 ImplChangeHighlightUpDn( false );
             }
             break;
         case KEY_HOME:
             {
-                ImplChangeHighlight( NULL );
+                ImplChangeHighlight( nullptr );
                 ImplChangeHighlightUpDn( true );
             }
             break;
@@ -5235,7 +5235,7 @@ void ToolBox::KeyInput( const KeyEvent& rKEvt )
         default:
             {
             sal_uInt16 aKeyGroup = aKeyCode.GetGroup();
-            ImplToolItem *pItem = NULL;
+            ImplToolItem *pItem = nullptr;
             if( mnHighItemId )
                 pItem = ImplGetItem( mnHighItemId );
             // #i13931# forward alphanum keyinput into embedded control
@@ -5306,7 +5306,7 @@ sal_uInt16 ToolBox::ImplGetItemLine( ImplToolItem* pCurrentItem )
 ImplToolItem* ToolBox::ImplGetFirstValidItem( sal_uInt16 nLine )
 {
     if( !nLine || nLine > mnCurLines )
-        return NULL;
+        return nullptr;
 
     nLine--;
 
@@ -5324,14 +5324,14 @@ ImplToolItem* ToolBox::ImplGetFirstValidItem( sal_uInt16 nLine )
             {
                 ++it;
                 if( it == mpData->m_aItems.end() || it->mbBreak )
-                    return NULL;    // no valid items in this line
+                    return nullptr;    // no valid items in this line
             }
             return &(*it);
         }
         ++it;
     }
 
-    return (it == mpData->m_aItems.end()) ? NULL : &(*it);
+    return (it == mpData->m_aItems.end()) ? nullptr : &(*it);
 }
 
 sal_uInt16 ToolBox::ImplFindItemPos( const ImplToolItem* pItem, const std::vector< ImplToolItem >& rList )
@@ -5362,7 +5362,7 @@ void ToolBox::ImplChangeHighlight( ImplToolItem* pItem, bool bNoGrabFocus )
 
     mbChangingHighlight = true;
 
-    ImplToolItem* pOldItem = NULL;
+    ImplToolItem* pOldItem = nullptr;
 
     if ( mnHighItemId )
     {
@@ -5452,7 +5452,7 @@ bool ToolBox::ImplChangeHighlightUpDn( bool bUp, bool bNoCycle )
             {
                 // select last valid non-clipped item
                 std::vector< ImplToolItem >::iterator it = mpData->m_aItems.end();
-                ImplToolItem* pItem = NULL;
+                ImplToolItem* pItem = nullptr;
                 while( it != mpData->m_aItems.begin() )
                 {
                     --it;
@@ -5498,11 +5498,11 @@ bool ToolBox::ImplChangeHighlightUpDn( bool bUp, bool bNoCycle )
             // select the menu button if a clipped item would be selected
             if( (it != mpData->m_aItems.end() && &(*it) == ImplGetFirstClippedItem( this )) && IsMenuEnabled() )
             {
-                ImplChangeHighlight( NULL );
+                ImplChangeHighlight( nullptr );
                 InvalidateMenuButton();
             }
             else
-                ImplChangeHighlight( (it != mpData->m_aItems.end()) ? &(*it) : NULL );
+                ImplChangeHighlight( (it != mpData->m_aItems.end()) ? &(*it) : nullptr );
             return true;
         }
         else
@@ -5512,13 +5512,13 @@ bool ToolBox::ImplChangeHighlightUpDn( bool bUp, bool bNoCycle )
             // docked toolbars have the menubutton as last item - if this button is enabled
             if( IsMenuEnabled() && !ImplIsFloatingMode() )
             {
-                ImplChangeHighlight( NULL );
+                ImplChangeHighlight( nullptr );
                 InvalidateMenuButton();
             }
             else
             {
                 std::vector< ImplToolItem >::iterator it = mpData->m_aItems.end();
-                ImplToolItem* pItem = NULL;
+                ImplToolItem* pItem = nullptr;
                 while( it != mpData->m_aItems.begin() )
                 {
                     --it;
@@ -5552,7 +5552,7 @@ bool ToolBox::ImplChangeHighlightUpDn( bool bUp, bool bNoCycle )
                     // highlight the menu button if it is the last item
                     if( IsMenuEnabled() && !ImplIsFloatingMode() )
                     {
-                        ImplChangeHighlight( NULL );
+                        ImplChangeHighlight( nullptr );
                         InvalidateMenuButton();
                         return true;
                     }
@@ -5570,7 +5570,7 @@ bool ToolBox::ImplChangeHighlightUpDn( bool bUp, bool bNoCycle )
                     // highlight the menu button if it is the last item
                     if( IsMenuEnabled() && !ImplIsFloatingMode() )
                     {
-                        ImplChangeHighlight( NULL );
+                        ImplChangeHighlight( nullptr );
                         InvalidateMenuButton();
                         return true;
                     }
@@ -5589,7 +5589,7 @@ bool ToolBox::ImplChangeHighlightUpDn( bool bUp, bool bNoCycle )
         if( pToolItem->IsClipped() && IsMenuEnabled() )
         {
             // select the menu button if a clipped item would be selected
-            ImplChangeHighlight( NULL );
+            ImplChangeHighlight( nullptr );
             InvalidateMenuButton();
         }
         else if( i != nCount )
diff --git a/vcl/source/window/toolbox2.cxx b/vcl/source/window/toolbox2.cxx
index f8dd351fab23..b2b6adf2e969 100644
--- a/vcl/source/window/toolbox2.cxx
+++ b/vcl/source/window/toolbox2.cxx
@@ -51,11 +51,11 @@ using namespace com::sun::star;
 #define TB_SEP_SIZE             8
 
 ImplToolBoxPrivateData::ImplToolBoxPrivateData() :
-        m_pLayoutData( NULL )
+        m_pLayoutData( nullptr )
 {
     meButtonSize = TOOLBOX_BUTTONSIZE_DONTCARE;
     mpMenu = new PopupMenu();
-    mnEventId = 0;
+    mnEventId = nullptr;
 
     maMenuType = TOOLBOX_MENUTYPE_NONE;
     maMenubuttonItem.maItemSize = Size( TB_MENUBUTTON_SIZE+TB_MENUBUTTON_OFFSET, TB_MENUBUTTON_SIZE+TB_MENUBUTTON_OFFSET );
@@ -85,8 +85,8 @@ void ImplToolItem::init(sal_uInt16 nItemId, ToolBoxItemBits nItemBits,
                         bool bEmptyBtn)
 {
     mnId            = nItemId;
-    mpWindow        = NULL;
-    mpUserData      = NULL;
+    mpWindow        = nullptr;
+    mpUserData      = nullptr;
     meType          = ToolBoxItemType::BUTTON;
     mnBits          = nItemBits;
     meState         = TRISTATE_FALSE;
@@ -744,7 +744,7 @@ void ToolBox::CopyItem( const ToolBox& rToolBox, sal_uInt16 nItemId,
         // push ToolBox item onto the list
         ImplToolItem aNewItem = rToolBox.mpData->m_aItems[nPos];
         // reset state
-        aNewItem.mpWindow      = NULL;
+        aNewItem.mpWindow      = nullptr;
         aNewItem.mbShowWindow = false;
 
         mpData->m_aItems.insert( (nNewPos < mpData->m_aItems.size()) ? mpData->m_aItems.begin()+nNewPos : mpData->m_aItems.end(), aNewItem );
@@ -1110,7 +1110,7 @@ void* ToolBox::GetItemData( sal_uInt16 nItemId ) const
     if ( pItem )
         return pItem->mpUserData;
     else
-        return NULL;
+        return nullptr;
 }
 
 void ToolBox::SetItemImage( sal_uInt16 nItemId, const Image& rImage )
@@ -1315,7 +1315,7 @@ vcl::Window* ToolBox::GetItemWindow( sal_uInt16 nItemId ) const
     if ( pItem )
         return pItem->mpWindow;
     else
-        return NULL;
+        return nullptr;
 }
 
 void ToolBox::StartSelection()
@@ -1863,7 +1863,7 @@ IMPL_LINK_TYPED( ToolBox, ImplCustomMenuListener, VclMenuEvent&, rEvent, void )
 
 IMPL_LINK_NOARG_TYPED(ToolBox, ImplCallExecuteCustomMenu, void*, void)
 {
-    mpData->mnEventId = 0;
+    mpData->mnEventId = nullptr;
     ImplExecuteCustomMenu();
 }
 
@@ -1939,7 +1939,7 @@ void ToolBox::ExecuteCustomMenu()
         // handle custom menu asynchronously
         // to avoid problems if the toolbox is closed during menu execute
         UpdateCustomMenu();
-        mpData->mnEventId = Application::PostUserEvent( LINK( this, ToolBox, ImplCallExecuteCustomMenu ), NULL, true );
+        mpData->mnEventId = Application::PostUserEvent( LINK( this, ToolBox, ImplCallExecuteCustomMenu ), nullptr, true );
     }
 }
 
diff --git a/vcl/source/window/window.cxx b/vcl/source/window/window.cxx
index c7f4fd615fd9..48be7171a994 100644
--- a/vcl/source/window/window.cxx
+++ b/vcl/source/window/window.cxx
@@ -93,16 +93,16 @@ Window::Window( vcl::Window* pParent, WinBits nStyle )
 {
 
     ImplInitWindowData( WINDOW_WINDOW );
-    ImplInit( pParent, nStyle, NULL );
+    ImplInit( pParent, nStyle, nullptr );
 }
 
 Window::Window( vcl::Window* pParent, const ResId& rResId )
-    : mpWindowImpl(NULL)
+    : mpWindowImpl(nullptr)
 {
     rResId.SetRT( RSC_WINDOW );
     WinBits nStyle = ImplInitRes( rResId );
     ImplInitWindowData( WINDOW_WINDOW );
-    ImplInit( pParent, nStyle, NULL );
+    ImplInit( pParent, nStyle, nullptr );
     ImplLoadRes( rResId );
 
     if ( !(nStyle & WB_HIDE) )
@@ -258,7 +258,7 @@ void Window::dispose()
     if ( pSVData->maWinData.mpCaptureWin == this )
         ReleaseMouse();
     if ( pSVData->maWinData.mpDefDialogParent == this )
-        pSVData->maWinData.mpDefDialogParent = NULL;
+        pSVData->maWinData.mpDefDialogParent = nullptr;
 
 #if OSL_DEBUG_LEVEL > 0
     if ( true ) // always perform these tests in debug builds
@@ -282,7 +282,7 @@ void Window::dispose()
             Application::Abort(OStringToOUString(aTempStr.makeStringAndClear(), RTL_TEXTENCODING_UTF8));   // abort in debug builds, this must be fixed!
         }
 
-        if (mpWindowImpl->mpFrameData != 0)
+        if (mpWindowImpl->mpFrameData != nullptr)
         {
             pTempWin = mpWindowImpl->mpFrameData->mpFirstOverlap;
             while ( pTempWin )
@@ -345,7 +345,7 @@ void Window::dispose()
         }
 
         vcl::Window* pMyParent = GetParent();
-        SystemWindow* pMySysWin = NULL;
+        SystemWindow* pMySysWin = nullptr;
 
         while ( pMyParent )
         {
@@ -369,7 +369,7 @@ void Window::dispose()
     if( mpWindowImpl->mbIsInTaskPaneList )
     {
         vcl::Window* pMyParent = GetParent();
-        SystemWindow* pMySysWin = NULL;
+        SystemWindow* pMySysWin = nullptr;
 
         while ( pMyParent )
         {
@@ -416,7 +416,7 @@ void Window::dispose()
     {
         EndExtTextInput( EndExtTextInputFlags::Complete );
         if ( pSVData->maWinData.mpExtTextInputWin == this )
-            pSVData->maWinData.mpExtTextInputWin = NULL;
+            pSVData->maWinData.mpExtTextInputWin = nullptr;
     }
 
     // check if the focus window is our child
@@ -442,8 +442,8 @@ void Window::dispose()
     {
         if ( mpWindowImpl->mbFrame )
         {
-            pSVData->maWinData.mpFocusWin = NULL;
-            pOverlapWindow->mpWindowImpl->mpLastFocusWindow = NULL;
+            pSVData->maWinData.mpFocusWin = nullptr;
+            pOverlapWindow->mpWindowImpl->mpLastFocusWindow = nullptr;
         }
         else
         {
@@ -467,43 +467,43 @@ void Window::dispose()
             // If the focus was set back to 'this' set it to nothing
             if ( pSVData->maWinData.mpFocusWin == this )
             {
-                pSVData->maWinData.mpFocusWin = NULL;
-                pOverlapWindow->mpWindowImpl->mpLastFocusWindow = NULL;
+                pSVData->maWinData.mpFocusWin = nullptr;
+                pOverlapWindow->mpWindowImpl->mpLastFocusWindow = nullptr;
             }
         }
     }
 
-    if ( pOverlapWindow != 0 &&
+    if ( pOverlapWindow != nullptr &&
          pOverlapWindow->mpWindowImpl->mpLastFocusWindow == this )
-        pOverlapWindow->mpWindowImpl->mpLastFocusWindow = NULL;
+        pOverlapWindow->mpWindowImpl->mpLastFocusWindow = nullptr;
 
     // reset hint for DefModalDialogParent
     if( pSVData->maWinData.mpActiveApplicationFrame == this )
-        pSVData->maWinData.mpActiveApplicationFrame = NULL;
+        pSVData->maWinData.mpActiveApplicationFrame = nullptr;
 
     // reset marked windows
-    if ( mpWindowImpl->mpFrameData != 0 )
+    if ( mpWindowImpl->mpFrameData != nullptr )
     {
         if ( mpWindowImpl->mpFrameData->mpFocusWin == this )
-            mpWindowImpl->mpFrameData->mpFocusWin = NULL;
+            mpWindowImpl->mpFrameData->mpFocusWin = nullptr;
         if ( mpWindowImpl->mpFrameData->mpMouseMoveWin == this )
-            mpWindowImpl->mpFrameData->mpMouseMoveWin = NULL;
+            mpWindowImpl->mpFrameData->mpMouseMoveWin = nullptr;
         if ( mpWindowImpl->mpFrameData->mpMouseDownWin == this )
-            mpWindowImpl->mpFrameData->mpMouseDownWin = NULL;
+            mpWindowImpl->mpFrameData->mpMouseDownWin = nullptr;
     }
 
     // reset Deactivate-Window
     if ( pSVData->maWinData.mpLastDeacWin == this )
-        pSVData->maWinData.mpLastDeacWin = NULL;
+        pSVData->maWinData.mpLastDeacWin = nullptr;
 
     if ( mpWindowImpl->mpFrameData )
     {
         if ( mpWindowImpl->mpFrameData->mnFocusId )
             Application::RemoveUserEvent( mpWindowImpl->mpFrameData->mnFocusId );
-        mpWindowImpl->mpFrameData->mnFocusId = NULL;
+        mpWindowImpl->mpFrameData->mnFocusId = nullptr;
         if ( mpWindowImpl->mpFrameData->mnMouseMoveId )
             Application::RemoveUserEvent( mpWindowImpl->mpFrameData->mnMouseMoveId );
-        mpWindowImpl->mpFrameData->mnMouseMoveId = NULL;
+        mpWindowImpl->mpFrameData->mnMouseMoveId = nullptr;
     }
 
     // release SalGraphics
@@ -568,15 +568,15 @@ void Window::dispose()
             assert (mpWindowImpl->mpFrameData->mpNextFrame.get() != pSysWin);
             pSysWin->mpWindowImpl->mpFrameData->mpNextFrame = mpWindowImpl->mpFrameData->mpNextFrame;
         }
-        mpWindowImpl->mpFrame->SetCallback( NULL, NULL );
+        mpWindowImpl->mpFrame->SetCallback( nullptr, nullptr );
         pSVData->mpDefInst->DestroyFrame( mpWindowImpl->mpFrame );
-        assert (mpWindowImpl->mpFrameData->mnFocusId == NULL);
-        assert (mpWindowImpl->mpFrameData->mnMouseMoveId == NULL);
+        assert (mpWindowImpl->mpFrameData->mnFocusId == nullptr);
+        assert (mpWindowImpl->mpFrameData->mnMouseMoveId == nullptr);
         delete mpWindowImpl->mpFrameData;
     }
 
     // should be the last statements
-    delete mpWindowImpl; mpWindowImpl = NULL;
+    delete mpWindowImpl; mpWindowImpl = nullptr;
 
     OutputDevice::dispose();
 }
@@ -611,32 +611,32 @@ WindowImpl::WindowImpl( WindowType nType )
     maZoom                              = Fraction( 1, 1 );
     maWinRegion                         = vcl::Region(true);
     maWinClipRegion                     = vcl::Region(true);
-    mpWinData                           = NULL;                      // Extra Window Data, that we don't need for all windows
-    mpOverlapData                       = NULL;                      // Overlap Data
-    mpFrameData                         = NULL;                      // Frame Data
-    mpFrame                             = NULL;                      // Pointer to frame window
-    mpSysObj                            = NULL;
-    mpFrameWindow                       = NULL;                      // window to top level parent (same as frame window)
-    mpOverlapWindow                     = NULL;                      // first overlap parent
-    mpBorderWindow                      = NULL;                      // Border-Window
-    mpClientWindow                      = NULL;                      // Client-Window of a FrameWindow
-    mpParent                            = NULL;                      // parent (incl. BorderWindow)
-    mpRealParent                        = NULL;                      // real parent (excl. BorderWindow)
-    mpFirstChild                        = NULL;                      // first child window
-    mpLastChild                         = NULL;                      // last child window
-    mpFirstOverlap                      = NULL;                      // first overlap window (only set in overlap windows)
-    mpLastOverlap                       = NULL;                      // last overlap window (only set in overlap windows)
-    mpPrev                              = NULL;                      // prev window
-    mpNext                              = NULL;                      // next window
-    mpNextOverlap                       = NULL;                      // next overlap window of frame
-    mpLastFocusWindow                   = NULL;                      // window for focus restore
-    mpDlgCtrlDownWindow                 = NULL;                      // window for dialog control
-    mpFirstDel                          = NULL;                      // Dtor notification list
-    mpUserData                          = NULL;                      // user data
-    mpCursor                            = NULL;                      // cursor
-    mpControlFont                       = NULL;                      // font properties
-    mpVCLXWindow                        = NULL;
-    mpAccessibleInfos                   = NULL;
+    mpWinData                           = nullptr;                      // Extra Window Data, that we don't need for all windows
+    mpOverlapData                       = nullptr;                      // Overlap Data
+    mpFrameData                         = nullptr;                      // Frame Data
+    mpFrame                             = nullptr;                      // Pointer to frame window
+    mpSysObj                            = nullptr;
+    mpFrameWindow                       = nullptr;                      // window to top level parent (same as frame window)
+    mpOverlapWindow                     = nullptr;                      // first overlap parent
+    mpBorderWindow                      = nullptr;                      // Border-Window
+    mpClientWindow                      = nullptr;                      // Client-Window of a FrameWindow
+    mpParent                            = nullptr;                      // parent (incl. BorderWindow)
+    mpRealParent                        = nullptr;                      // real parent (excl. BorderWindow)
+    mpFirstChild                        = nullptr;                      // first child window
+    mpLastChild                         = nullptr;                      // last child window
+    mpFirstOverlap                      = nullptr;                      // first overlap window (only set in overlap windows)
+    mpLastOverlap                       = nullptr;                      // last overlap window (only set in overlap windows)
+    mpPrev                              = nullptr;                      // prev window
+    mpNext                              = nullptr;                      // next window
+    mpNextOverlap                       = nullptr;                      // next overlap window of frame
+    mpLastFocusWindow                   = nullptr;                      // window for focus restore
+    mpDlgCtrlDownWindow                 = nullptr;                      // window for dialog control
+    mpFirstDel                          = nullptr;                      // Dtor notification list
+    mpUserData                          = nullptr;                      // user data
+    mpCursor                            = nullptr;                      // cursor
+    mpControlFont                       = nullptr;                      // font properties
+    mpVCLXWindow                        = nullptr;
+    mpAccessibleInfos                   = nullptr;
     maControlForeground                 = Color( COL_TRANSPARENT );  // no foreground set
     maControlBackground                 = Color( COL_TRANSPARENT );  // no background set
     mnLeftBorder                        = 0;                         // left border
@@ -650,8 +650,8 @@ WindowImpl::WindowImpl( WindowType nType )
     mnX                                 = 0;                         // X-Position to Parent
     mnY                                 = 0;                         // Y-Position to Parent
     mnAbsScreenX                        = 0;                         // absolute X-position on screen, used for RTL window positioning
-    mpChildClipRegion                   = NULL;                      // Child-Clip-Region when ClipChildren
-    mpPaintRegion                       = NULL;                      // Paint-ClipRegion
+    mpChildClipRegion                   = nullptr;                      // Child-Clip-Region when ClipChildren
+    mpPaintRegion                       = nullptr;                      // Paint-ClipRegion
     mnStyle                             = 0;                         // style (init in ImplInitWindow)
     mnPrevStyle                         = 0;                         // prevstyle (set in SetStyle)
     mnExtendedStyle                     = 0;                         // extended style (init in ImplInitWindow)
@@ -863,9 +863,9 @@ void Window::ReleaseGraphics( bool bRelease )
     else
         pSVData->maGDIData.mpLastWinGraphics = mpPrevGraphics;
 
-    mpGraphics      = NULL;
-    mpPrevGraphics  = NULL;
-    mpNextGraphics  = NULL;
+    mpGraphics      = nullptr;
+    mpPrevGraphics  = nullptr;
+    mpNextGraphics  = nullptr;
 }
 
 static sal_Int32 CountDPIScaleFactor(sal_Int32 nDPI)
@@ -933,9 +933,9 @@ void Window::ImplInit( vcl::Window* pParent, WinBits nStyle, SystemParentData* p
     if ( mpWindowImpl->mbOverlapWin )
     {
         mpWindowImpl->mpOverlapData                   = new ImplOverlapData;
-        mpWindowImpl->mpOverlapData->mpSaveBackDev    = NULL;
-        mpWindowImpl->mpOverlapData->mpSaveBackRgn    = NULL;
-        mpWindowImpl->mpOverlapData->mpNextBackWin    = NULL;
+        mpWindowImpl->mpOverlapData->mpSaveBackDev    = nullptr;
+        mpWindowImpl->mpOverlapData->mpSaveBackRgn    = nullptr;
+        mpWindowImpl->mpOverlapData->mpNextBackWin    = nullptr;
         mpWindowImpl->mpOverlapData->mnSaveBackSize   = 0;
         mpWindowImpl->mpOverlapData->mbSaveBack       = false;
         mpWindowImpl->mpOverlapData->mnTopLevel       = 1;
@@ -1001,7 +1001,7 @@ void Window::ImplInit( vcl::Window* pParent, WinBits nStyle, SystemParentData* p
                 break;
         }
 
-        SalFrame* pParentFrame = NULL;
+        SalFrame* pParentFrame = nullptr;
         if ( pParent )
             pParentFrame = pParent->mpWindowImpl->mpFrame;
         SalFrame* pFrame;
@@ -1029,16 +1029,16 @@ void Window::ImplInit( vcl::Window* pParent, WinBits nStyle, SystemParentData* p
         assert (pSVData->maWinData.mpFirstFrame.get() != this);
         mpWindowImpl->mpFrameData->mpNextFrame        = pSVData->maWinData.mpFirstFrame;
         pSVData->maWinData.mpFirstFrame = this;
-        mpWindowImpl->mpFrameData->mpFirstOverlap     = NULL;
-        mpWindowImpl->mpFrameData->mpFocusWin         = NULL;
-        mpWindowImpl->mpFrameData->mpMouseMoveWin     = NULL;
-        mpWindowImpl->mpFrameData->mpMouseDownWin     = NULL;
-        mpWindowImpl->mpFrameData->mpFirstBackWin     = NULL;
+        mpWindowImpl->mpFrameData->mpFirstOverlap     = nullptr;
+        mpWindowImpl->mpFrameData->mpFocusWin         = nullptr;
+        mpWindowImpl->mpFrameData->mpMouseMoveWin     = nullptr;
+        mpWindowImpl->mpFrameData->mpMouseDownWin     = nullptr;
+        mpWindowImpl->mpFrameData->mpFirstBackWin     = nullptr;
         mpWindowImpl->mpFrameData->mpFontCollection   = pSVData->maGDIData.mpScreenFontList;
         mpWindowImpl->mpFrameData->mpFontCache        = pSVData->maGDIData.mpScreenFontCache;
         mpWindowImpl->mpFrameData->mnAllSaveBackSize  = 0;
-        mpWindowImpl->mpFrameData->mnFocusId          = 0;
-        mpWindowImpl->mpFrameData->mnMouseMoveId      = 0;
+        mpWindowImpl->mpFrameData->mnFocusId          = nullptr;
+        mpWindowImpl->mpFrameData->mnMouseMoveId      = nullptr;
         mpWindowImpl->mpFrameData->mnLastMouseX       = -1;
         mpWindowImpl->mpFrameData->mnLastMouseY       = -1;
         mpWindowImpl->mpFrameData->mnBeforeLastMouseX = -1;
@@ -1259,7 +1259,7 @@ void Window::drawFrameDev( const Point& rPt, const Point& rDevPt, const Size& rD
     GDIMetaFile*    pOldMetaFile = mpMetaFile;
     bool            bOldMap = mbMap;
     RasterOp        eOldROP = GetRasterOp();
-    mpMetaFile = NULL;
+    mpMetaFile = nullptr;
     mbMap = false;
     SetRasterOp( ROP_OVERPAINT );
 
@@ -1297,14 +1297,14 @@ ImplWinData* Window::ImplGetWinData() const
         static const char* pNoNWF = getenv( "SAL_NO_NWF" );
 
         const_cast<vcl::Window*>(this)->mpWindowImpl->mpWinData = new ImplWinData;
-        mpWindowImpl->mpWinData->mpExtOldText     = NULL;
-        mpWindowImpl->mpWinData->mpExtOldAttrAry  = NULL;
-        mpWindowImpl->mpWinData->mpCursorRect     = NULL;
+        mpWindowImpl->mpWinData->mpExtOldText     = nullptr;
+        mpWindowImpl->mpWinData->mpExtOldAttrAry  = nullptr;
+        mpWindowImpl->mpWinData->mpCursorRect     = nullptr;
         mpWindowImpl->mpWinData->mnCursorExtWidth = 0;
-        mpWindowImpl->mpWinData->mpCompositionCharRects = NULL;
+        mpWindowImpl->mpWinData->mpCompositionCharRects = nullptr;
         mpWindowImpl->mpWinData->mnCompositionCharRects = 0;
-        mpWindowImpl->mpWinData->mpFocusRect      = NULL;
-        mpWindowImpl->mpWinData->mpTrackRect      = NULL;
+        mpWindowImpl->mpWinData->mpFocusRect      = nullptr;
+        mpWindowImpl->mpWinData->mpTrackRect      = nullptr;
         mpWindowImpl->mpWinData->mnTrackFlags     = 0;
         mpWindowImpl->mpWinData->mnIsTopWindow  = (sal_uInt16) ~0;  // not initialized yet, 0/1 will indicate TopWindow (see IsTopWindow())
         mpWindowImpl->mpWinData->mbMouseOver      = false;
@@ -1352,7 +1352,7 @@ SalGraphics* Window::ImplGetFrameGraphics() const
         OutputDevice* pFrameWinOutDev = mpWindowImpl->mpFrameWindow;
         if ( ! pFrameWinOutDev->AcquireGraphics() )
         {
-            return NULL;
+            return nullptr;
         }
     }
     mpWindowImpl->mpFrameWindow->mpGraphics->ResetClipRegion();
@@ -1418,7 +1418,7 @@ void Window::ImplAddDel( ImplDelData* pDel ) // TODO: make "const" when incompat
 
 void Window::ImplRemoveDel( ImplDelData* pDel ) // TODO: make "const" when incompatibility ok
 {
-    pDel->mpWindow = NULL;      // #112873# pDel is not associated with a Window anymore
+    pDel->mpWindow = nullptr;      // #112873# pDel is not associated with a Window anymore
 
     if ( IsDisposed() )
         return;
@@ -1577,8 +1577,8 @@ void Window::ImplPosSizeWindow( long nX, long nY,
     long    nOldOutOffY     = mnOutOffY;
     long    nOldOutWidth    = mnOutWidth;
     long    nOldOutHeight   = mnOutHeight;
-    vcl::Region* pOverlapRegion  = NULL;
-    vcl::Region* pOldRegion      = NULL;
+    vcl::Region* pOverlapRegion  = nullptr;
+    vcl::Region* pOldRegion      = nullptr;
 
     if ( IsReallyVisible() )
     {
@@ -1829,7 +1829,7 @@ void Window::ImplPosSizeWindow( long nX, long nY,
                     else
                         bInvalidate = true;
                     if ( bInvalidate )
-                        ImplInvalidateFrameRegion( NULL, InvalidateFlags::Children );
+                        ImplInvalidateFrameRegion( nullptr, InvalidateFlags::Children );
                 }
                 else
                 {
@@ -1888,8 +1888,8 @@ void Window::ImplNewInputContext()
     SalInputContext         aNewContext;
     const vcl::Font&        rFont = rInputContext.GetFont();
     const OUString&         rFontName = rFont.GetName();
-    ImplFontEntry*          pFontEntry = NULL;
-    aNewContext.mpFont = NULL;
+    ImplFontEntry*          pFontEntry = nullptr;
+    aNewContext.mpFont = nullptr;
     if (!rFontName.isEmpty())
     {
         OutputDevice *pFocusWinOutDev = pFocusWin->GetOutDev();
@@ -2153,8 +2153,8 @@ void Window::SetBorderStyle( WindowBorderStyle nBorderStyle )
             // borders in case of NWF drawing. So they need a method to remove their border window
             VclPtr<vcl::Window> pBorderWin = mpWindowImpl->mpBorderWindow;
             // remove us as border window's client
-            pBorderWin->mpWindowImpl->mpClientWindow = NULL;
-            mpWindowImpl->mpBorderWindow = NULL;
+            pBorderWin->mpWindowImpl->mpClientWindow = nullptr;
+            mpWindowImpl->mpBorderWindow = nullptr;
             mpWindowImpl->mpRealParent = pBorderWin->mpWindowImpl->mpParent;
             // reparent us above the border window
             SetParent( pBorderWin->mpWindowImpl->mpParent );
@@ -2246,7 +2246,7 @@ void Window::SetCursorRect( const Rectangle* pRect, long nExtTextInputWidth )
         else
         {
             delete pWinData->mpCursorRect;
-            pWinData->mpCursorRect = NULL;
+            pWinData->mpCursorRect = nullptr;
         }
     }
     else
@@ -2278,7 +2278,7 @@ void Window::SetCompositionCharRect( const Rectangle* pRect, long nCompositionLe
     ImplWinData* pWinData = ImplGetWinData();
     delete[] pWinData->mpCompositionCharRects;
     pWinData->mbVertical = bVertical;
-    pWinData->mpCompositionCharRects = NULL;
+    pWinData->mpCompositionCharRects = nullptr;
     pWinData->mnCompositionCharRects = nCompositionLength;
     if ( pRect && (nCompositionLength > 0) )
     {
@@ -2468,7 +2468,7 @@ void Window::Show(bool bVisible, ShowFlags nFlags)
                 InvalidateFlags nInvalidateFlags = InvalidateFlags::Children;
                 if( ! IsPaintTransparent() )
                     nInvalidateFlags |= InvalidateFlags::NoTransparent;
-                ImplInvalidate( NULL, nInvalidateFlags );
+                ImplInvalidate( nullptr, nInvalidateFlags );
                 ImplGenerateMouseMove();
             }
         }
@@ -2555,7 +2555,7 @@ Size Window::GetSizePixel() const
     {
         ImplDelData aDogtag( const_cast<Window*>(this) );
         mpWindowImpl->mpFrameData->maResizeIdle.Stop();
-        mpWindowImpl->mpFrameData->maResizeIdle.GetIdleHdl().Call( NULL );
+        mpWindowImpl->mpFrameData->maResizeIdle.GetIdleHdl().Call( nullptr );
         if( aDogtag.IsDead() )
             return Size(0,0);
     }
@@ -3400,7 +3400,7 @@ Reference< XClipboard > Window::GetClipboard()
         return mpWindowImpl->mpFrameData->mxClipboard;
     }
 
-    return static_cast < XClipboard * > (0);
+    return static_cast < XClipboard * > (nullptr);
 }
 
 Reference< XClipboard > Window::GetPrimarySelection()
@@ -3443,7 +3443,7 @@ Reference< XClipboard > Window::GetPrimarySelection()
         return mpWindowImpl->mpFrameData->mxSelection;
     }
 
-    return static_cast < XClipboard * > (0);
+    return static_cast < XClipboard * > (nullptr);
 }
 
 void Window::RecordLayoutData( vcl::ControlLayoutData* pLayout, const Rectangle& rRect )
@@ -3452,12 +3452,12 @@ void Window::RecordLayoutData( vcl::ControlLayoutData* pLayout, const Rectangle&
     mpOutDevData->mpRecordLayout = pLayout;
     mpOutDevData->maRecordRect = rRect;
     Paint(*this, rRect);
-    mpOutDevData->mpRecordLayout = NULL;
+    mpOutDevData->mpRecordLayout = nullptr;
 }
 
 void Window::DrawSelectionBackground( const Rectangle& rRect, sal_uInt16 highlight, bool bChecked, bool bDrawBorder, bool bDrawExtBorderOnly )
 {
-    DrawSelectionBackground( rRect, highlight, bChecked, bDrawBorder, bDrawExtBorderOnly, 0, NULL, NULL );
+    DrawSelectionBackground( rRect, highlight, bChecked, bDrawBorder, bDrawExtBorderOnly, 0, nullptr, nullptr );
 }
 
 void Window::DrawSelectionBackground( const Rectangle& rRect,
@@ -3662,7 +3662,7 @@ void Window::ImplIncModalCount()
         {
             pParent = pParent->GetParent();
         }
-        pFrameWindow = pParent ? pParent->mpWindowImpl->mpFrameWindow.get() : NULL;
+        pFrameWindow = pParent ? pParent->mpWindowImpl->mpFrameWindow.get() : nullptr;
     }
 }
 void Window::ImplDecModalCount()
@@ -3676,7 +3676,7 @@ void Window::ImplDecModalCount()
         {
             pParent = pParent->GetParent();
         }
-        pFrameWindow = pParent ? pParent->mpWindowImpl->mpFrameWindow.get() : NULL;
+        pFrameWindow = pParent ? pParent->mpWindowImpl->mpFrameWindow.get() : nullptr;
     }
 }
 
@@ -3897,7 +3897,7 @@ void Window::ApplySettings(vcl::RenderContext& /*rRenderContext*/)
 const SystemEnvData* Window::GetSystemData() const
 {
 
-    return mpWindowImpl->mpFrame ? mpWindowImpl->mpFrame->GetSystemData() : NULL;
+    return mpWindowImpl->mpFrame ? mpWindowImpl->mpFrame->GetSystemData() : nullptr;
 }
 
 Any Window::GetSystemDataAny() const
diff --git a/vcl/source/window/window2.cxx b/vcl/source/window/window2.cxx
index 5eaaf6f0eabe..d39810a8f44a 100644
--- a/vcl/source/window/window2.cxx
+++ b/vcl/source/window/window2.cxx
@@ -341,10 +341,10 @@ void Window::EndTracking( TrackingEventFlags nFlags )
         if ( pSVData->maWinData.mpTrackTimer )
         {
             delete pSVData->maWinData.mpTrackTimer;
-            pSVData->maWinData.mpTrackTimer = NULL;
+            pSVData->maWinData.mpTrackTimer = nullptr;
         }
 
-        pSVData->maWinData.mpTrackWin    = NULL;
+        pSVData->maWinData.mpTrackWin    = nullptr;
         pSVData->maWinData.mnTrackFlags  = StartTrackingFlags::NONE;
         ReleaseMouse();
         }
@@ -396,11 +396,11 @@ void Window::EndAutoScroll()
 
     if ( pSVData->maWinData.mpAutoScrollWin.get() == this )
     {
-        pSVData->maWinData.mpAutoScrollWin = NULL;
+        pSVData->maWinData.mpAutoScrollWin = nullptr;
         pSVData->maWinData.mnAutoScrollFlags = StartAutoScrollFlags::NONE;
         pSVData->maAppData.mpWheelWindow->ImplStop();
         pSVData->maAppData.mpWheelWindow->doLazyDelete();
-        pSVData->maAppData.mpWheelWindow = NULL;
+        pSVData->maAppData.mpWheelWindow = nullptr;
     }
 }
 
@@ -512,7 +512,7 @@ void Window::SetControlFont()
     if (mpWindowImpl && mpWindowImpl->mpControlFont)
     {
         delete mpWindowImpl->mpControlFont;
-        mpWindowImpl->mpControlFont = NULL;
+        mpWindowImpl->mpControlFont = nullptr;
         CompatStateChanged(StateChangedType::ControlFont);
     }
 }
@@ -762,7 +762,7 @@ bool Window::HandleScrollCommand( const CommandEvent& rCmd,
                             nLines = pData->GetNotchDelta() * (long)nScrollLines;
                         if ( nLines )
                         {
-                            ImplHandleScroll( NULL,
+                            ImplHandleScroll( nullptr,
                                           0L,
                                           pData->IsHorz() ? pHScrl : pVScrl,
                                           nLines );
@@ -931,27 +931,27 @@ vcl::Window* Window::ImplGetWindow()
 
 ImplFrameData* Window::ImplGetFrameData()
 {
-    return mpWindowImpl ? mpWindowImpl->mpFrameData : NULL;
+    return mpWindowImpl ? mpWindowImpl->mpFrameData : nullptr;
 }
 
 SalFrame* Window::ImplGetFrame() const
 {
-    return mpWindowImpl ? mpWindowImpl->mpFrame : NULL;
+    return mpWindowImpl ? mpWindowImpl->mpFrame : nullptr;
 }
 
 vcl::Window* Window::ImplGetParent() const
 {
-    return mpWindowImpl ? mpWindowImpl->mpParent.get() : NULL;
+    return mpWindowImpl ? mpWindowImpl->mpParent.get() : nullptr;
 }
 
 vcl::Window* Window::ImplGetClientWindow() const
 {
-    return mpWindowImpl ? mpWindowImpl->mpClientWindow.get() : NULL;
+    return mpWindowImpl ? mpWindowImpl->mpClientWindow.get() : nullptr;
 }
 
 vcl::Window* Window::ImplGetBorderWindow() const
 {
-    return mpWindowImpl ? mpWindowImpl->mpBorderWindow.get() : NULL;
+    return mpWindowImpl ? mpWindowImpl->mpBorderWindow.get() : nullptr;
 }
 
 vcl::Window* Window::ImplGetFirstOverlapWindow()
@@ -972,7 +972,7 @@ const vcl::Window* Window::ImplGetFirstOverlapWindow() const
 
 vcl::Window* Window::ImplGetFrameWindow() const
 {
-    return mpWindowImpl ? mpWindowImpl->mpFrameWindow.get() : NULL;
+    return mpWindowImpl ? mpWindowImpl->mpFrameWindow.get() : nullptr;
 }
 
 bool Window::IsDockingWindow() const
@@ -1148,7 +1148,7 @@ const InputContext& Window::GetInputContext() const
 
 bool Window::IsControlFont() const
 {
-    return (mpWindowImpl->mpControlFont != 0);
+    return (mpWindowImpl->mpControlFont != nullptr);
 }
 
 Color Window::GetControlForeground() const
@@ -1178,7 +1178,7 @@ bool Window::IsInPaint() const
 
 vcl::Window* Window::GetParent() const
 {
-    return mpWindowImpl ? mpWindowImpl->mpRealParent.get() : NULL;
+    return mpWindowImpl ? mpWindowImpl->mpRealParent.get() : nullptr;
 }
 
 bool Window::IsVisible() const
@@ -1280,7 +1280,7 @@ bool Window::IsWait() const
 vcl::Cursor* Window::GetCursor() const
 {
     if (!mpWindowImpl)
-        return NULL;
+        return nullptr;
     return mpWindowImpl->mpCursor;
 }
 
@@ -1338,7 +1338,7 @@ const Pointer& Window::GetPointer() const
 
 VCLXWindow* Window::GetWindowPeer() const
 {
-    return mpWindowImpl ? mpWindowImpl->mpVCLXWindow : NULL;
+    return mpWindowImpl ? mpWindowImpl->mpVCLXWindow : nullptr;
 }
 
 void Window::SetPosPixel( const Point& rNewPos )
@@ -2012,7 +2012,7 @@ void Window::remove_mnemonic_label(FixedText *pLabel)
     if (aFind == v.end())
         return;
     v.erase(aFind);
-    pLabel->set_mnemonic_widget(NULL);
+    pLabel->set_mnemonic_widget(nullptr);
 }
 
 std::vector<VclPtr<FixedText> > Window::list_mnemonic_labels() const
diff --git a/vcl/source/window/winproc.cxx b/vcl/source/window/winproc.cxx
index ae7272735451..544ea6e95d3a 100644
--- a/vcl/source/window/winproc.cxx
+++ b/vcl/source/window/winproc.cxx
@@ -196,8 +196,8 @@ static void ImplSetMousePointer( vcl::Window* pChild )
         pChild->ImplGetFrame()->SetPointer( pChild->ImplGetMousePointer() );
 }
 
-static bool ImplCallCommand( vcl::Window* pChild, CommandEventId nEvt, void* pData = NULL,
-                             bool bMouse = false, Point* pPos = NULL )
+static bool ImplCallCommand( vcl::Window* pChild, CommandEventId nEvt, void* pData = nullptr,
+                             bool bMouse = false, Point* pPos = nullptr )
 {
     Point aPos;
     if ( pPos )
@@ -255,7 +255,7 @@ static void ContextMenuEventLink( void* pCEvent, void* )
     if( ! pEv->aDelData.IsDead() )
     {
         pEv->pWindow->ImplRemoveDel( &pEv->aDelData );
-        ImplCallCommand( pEv->pWindow, CommandEventId::ContextMenu, NULL, true, &pEv->aChildPos );
+        ImplCallCommand( pEv->pWindow, CommandEventId::ContextMenu, nullptr, true, &pEv->aChildPos );
     }
     delete pEv;
 }
@@ -266,7 +266,7 @@ bool ImplHandleMouseEvent( vcl::Window* pWindow, MouseNotifyEvent nSVEvent, bool
 {
     ImplSVData* pSVData = ImplGetSVData();
     Point       aMousePos( nX, nY );
-    vcl::Window*     pChild(NULL);
+    vcl::Window*     pChild(nullptr);
     bool        bRet(false);
     sal_uInt16  nClicks(0);
     ImplFrameData* pWinFrameData = pWindow->ImplGetFrameData();
@@ -349,7 +349,7 @@ bool ImplHandleMouseEvent( vcl::Window* pWindow, MouseNotifyEvent nSVEvent, bool
     else
     {
         if ( bMouseLeave )
-            pChild = NULL;
+            pChild = nullptr;
         else
             pChild = pWindow->ImplFindWindow( aMousePos );
     }
@@ -488,7 +488,7 @@ bool ImplHandleMouseEvent( vcl::Window* pWindow, MouseNotifyEvent nSVEvent, bool
 
                                 // create a uno mouse event out of the available data
                                 ::com::sun::star::awt::MouseEvent aMouseEvent(
-                                    static_cast < ::com::sun::star::uno::XInterface * > ( 0 ),
+                                    static_cast < ::com::sun::star::uno::XInterface * > ( nullptr ),
 #ifdef MACOSX
                     nCode & (KEY_SHIFT | KEY_MOD1 | KEY_MOD2 | KEY_MOD3),
 #else
@@ -544,13 +544,13 @@ bool ImplHandleMouseEvent( vcl::Window* pWindow, MouseNotifyEvent nSVEvent, bool
                         aNLeaveEvt.GetWindow()->ImplNotifyKeyMouseCommandEventListeners( aNLeaveEvt );
                 }
 
-                pWinFrameData->mpMouseMoveWin = NULL;
+                pWinFrameData->mpMouseMoveWin = nullptr;
                 pWinFrameData->mbInMouseMove = false;
 
                 if ( pChild )
                 {
                     if ( aDelData2.IsDead() )
-                        pChild = NULL;
+                        pChild = nullptr;
                     else
                         pChild->ImplRemoveDel( &aDelData2 );
                 }
@@ -787,9 +787,9 @@ bool ImplHandleMouseEvent( vcl::Window* pWindow, MouseNotifyEvent nSVEvent, bool
             {
                 MouseMiddleButtonAction nMiddleAction = pChild->GetSettings().GetMouseSettings().GetMiddleButtonAction();
                 if ( nMiddleAction == MouseMiddleButtonAction::AutoScroll )
-                    bRet = !ImplCallCommand( pChild, CommandEventId::StartAutoScroll, NULL, true, &aChildPos );
+                    bRet = !ImplCallCommand( pChild, CommandEventId::StartAutoScroll, nullptr, true, &aChildPos );
                 else if ( nMiddleAction == MouseMiddleButtonAction::PasteSelection )
-                    bRet = !ImplCallCommand( pChild, CommandEventId::PasteSelection, NULL, true, &aChildPos );
+                    bRet = !ImplCallCommand( pChild, CommandEventId::PasteSelection, nullptr, true, &aChildPos );
             }
             else
             {
@@ -818,7 +818,7 @@ bool ImplHandleMouseEvent( vcl::Window* pWindow, MouseNotifyEvent nSVEvent, bool
                             Application::PostUserEvent( Link<void*,void>( pEv, ContextMenuEventLink ) );
                         }
                         else
-                            bRet = ! ImplCallCommand( pChild, CommandEventId::ContextMenu, NULL, true, &aChildPos );
+                            bRet = ! ImplCallCommand( pChild, CommandEventId::ContextMenu, nullptr, true, &aChildPos );
                     }
                 }
             }
@@ -836,8 +836,8 @@ static vcl::Window* ImplGetKeyInputWindow( vcl::Window* pWindow )
     pSVData->maAppData.mnLastInputTime = tools::Time::GetSystemTicks();
 
     // #127104# workaround for destroyed windows
-    if( pWindow->ImplGetWindowImpl() == NULL )
-        return 0;
+    if( pWindow->ImplGetWindowImpl() == nullptr )
+        return nullptr;
 
     // find window - is every time the window which has currently the
     // focus or the last time the focus.
@@ -853,7 +853,7 @@ static vcl::Window* ImplGetKeyInputWindow( vcl::Window* pWindow )
 
     // no child - than no input
     if ( !pChild )
-        return 0;
+        return nullptr;
 
     // We call also KeyInput if we haven't the focus, because on Unix
     // system this is often the case when a Lookup Choice Window has
@@ -864,7 +864,7 @@ static vcl::Window* ImplGetKeyInputWindow( vcl::Window* pWindow )
 
     // no keyinput to disabled windows
     if ( !pChild->IsEnabled() || !pChild->IsInputEnabled() || pChild->IsInModalMode() )
-        return 0;
+        return nullptr;
 
     return pChild;
 }
@@ -1153,7 +1153,7 @@ static bool ImplHandleExtTextInput( vcl::Window* pWindow,
                                     sal_Int32 nCursorPos, sal_uInt16 nCursorFlags )
 {
     ImplSVData* pSVData = ImplGetSVData();
-    vcl::Window*     pChild = NULL;
+    vcl::Window*     pChild = nullptr;
 
     int nTries = 200;
     while( nTries-- )
@@ -1180,7 +1180,7 @@ static bool ImplHandleExtTextInput( vcl::Window* pWindow,
         if ( pWinData->mpExtOldAttrAry )
         {
             delete [] pWinData->mpExtOldAttrAry;
-            pWinData->mpExtOldAttrAry = NULL;
+            pWinData->mpExtOldAttrAry = nullptr;
         }
         pSVData->maWinData.mpExtTextInputWin = pChild;
         ImplCallCommand( pChild, CommandEventId::StartExtTextInput );
@@ -1230,7 +1230,7 @@ static bool ImplHandleExtTextInput( vcl::Window* pWindow,
     if ( pWinData->mpExtOldAttrAry )
     {
         delete [] pWinData->mpExtOldAttrAry;
-        pWinData->mpExtOldAttrAry = NULL;
+        pWinData->mpExtOldAttrAry = nullptr;
     }
     if ( pTextAttr )
     {
@@ -1249,17 +1249,17 @@ static bool ImplHandleEndExtTextInput( vcl::Window* /* pWindow */ )
     if ( pChild )
     {
         pChild->ImplGetWindowImpl()->mbExtTextInput = false;
-        pSVData->maWinData.mpExtTextInputWin = NULL;
+        pSVData->maWinData.mpExtTextInputWin = nullptr;
         ImplWinData* pWinData = pChild->ImplGetWinData();
         if ( pWinData->mpExtOldText )
         {
             delete pWinData->mpExtOldText;
-            pWinData->mpExtOldText = NULL;
+            pWinData->mpExtOldText = nullptr;
         }
         if ( pWinData->mpExtOldAttrAry )
         {
             delete [] pWinData->mpExtOldAttrAry;
-            pWinData->mpExtOldAttrAry = NULL;
+            pWinData->mpExtOldAttrAry = nullptr;
         }
         nRet = !ImplCallCommand( pChild, CommandEventId::EndExtTextInput );
     }
@@ -1308,9 +1308,9 @@ static void ImplHandleExtTextInputPos( vcl::Window* pWindow,
         if ( !rInputWidth )
             rInputWidth = rRect.GetWidth();
     }
-    if (pVertical != 0)
+    if (pVertical != nullptr)
         *pVertical
-            = pChild != 0 && pChild->GetInputContext().GetFont().IsVertical();
+            = pChild != nullptr && pChild->GetInputContext().GetFont().IsVertical();
 }
 
 static bool ImplHandleInputContextChange( vcl::Window* pWindow, LanguageType eNewLang )
@@ -1395,7 +1395,7 @@ bool HandleGestureEventBase::Setup()
 vcl::Window* HandleGestureEventBase::FindTarget()
 {
     // first check any floating window ( eg. drop down listboxes)
-    vcl::Window *pMouseWindow = NULL;
+    vcl::Window *pMouseWindow = nullptr;
 
     if (m_pSVData->maWinData.mpFirstFloat && !m_pSVData->maWinData.mpCaptureWin &&
          !m_pSVData->maWinData.mpFirstFloat->ImplIsFloatPopupModeWindow( m_pWindow ) )
@@ -1433,7 +1433,7 @@ vcl::Window* HandleGestureEventBase::FindTarget()
 
 vcl::Window *HandleGestureEventBase::Dispatch(vcl::Window* pMouseWindow)
 {
-    vcl::Window *pDispatchedTo = NULL;
+    vcl::Window *pDispatchedTo = nullptr;
 
     if (acceptableWheelScrollTarget(pMouseWindow) && pMouseWindow->IsEnabled())
     {
@@ -1529,7 +1529,7 @@ bool HandleWheelEvent::HandleEvent(const SalWheelMouseEvent& rEvt)
 
     pPreviousWindow = Dispatch(pMouseWindow);
 
-    return pPreviousWindow != NULL;
+    return pPreviousWindow != nullptr;
 }
 
 class HandleGestureEvent : public HandleGestureEventBase
@@ -1549,7 +1549,7 @@ bool HandleGestureEvent::HandleEvent()
 
     vcl::Window *pTarget = FindTarget();
 
-    bool bHandled = Dispatch(pTarget) != NULL;
+    bool bHandled = Dispatch(pTarget) != nullptr;
     return bHandled;
 }
 
@@ -1771,7 +1771,7 @@ static void ImplActivateFloatingWindows( vcl::Window* pWindow, bool bActive )
 
 IMPL_LINK_NOARG_TYPED(vcl::Window, ImplAsyncFocusHdl, void*, void)
 {
-    ImplGetWindowImpl()->mpFrameData->mnFocusId = 0;
+    ImplGetWindowImpl()->mpFrameData->mnFocusId = nullptr;
 
     // If the status has been preserved, because we got back the focus
     // in the meantime, we do nothing
@@ -1829,7 +1829,7 @@ IMPL_LINK_NOARG_TYPED(vcl::Window, ImplAsyncFocusHdl, void*, void)
                 // FocusWindow umsetzen
                 vcl::Window* pOverlapWindow = pFocusWin->ImplGetFirstOverlapWindow();
                 pOverlapWindow->ImplGetWindowImpl()->mpLastFocusWindow = pFocusWin;
-                pSVData->maWinData.mpFocusWin = NULL;
+                pSVData->maWinData.mpFocusWin = nullptr;
 
                 if ( pFocusWin->ImplGetWindowImpl()->mpCursor )
                     pFocusWin->ImplGetWindowImpl()->mpCursor->ImplHide( true );
@@ -1864,7 +1864,7 @@ IMPL_LINK_NOARG_TYPED(vcl::Window, ImplAsyncFocusHdl, void*, void)
                     NotifyEvent aNEvt( MouseNotifyEvent::LOSEFOCUS, pFocusWin );
                     if ( !ImplCallPreNotify( aNEvt ) )
                         pFocusWin->CompatLoseFocus();
-                    pFocusWin->ImplCallDeactivateListeners( NULL );
+                    pFocusWin->ImplCallDeactivateListeners( nullptr );
                 }
                 // XXX
             }
@@ -1885,7 +1885,7 @@ static void ImplHandleGetFocus( vcl::Window* pWindow )
     if ( !pWindow->ImplGetWindowImpl()->mpFrameData->mnFocusId )
     {
         pWindow->ImplGetWindowImpl()->mpFrameData->mbStartFocusState = !pWindow->ImplGetWindowImpl()->mpFrameData->mbHasFocus;
-        pWindow->ImplGetWindowImpl()->mpFrameData->mnFocusId = Application::PostUserEvent( LINK( pWindow, vcl::Window, ImplAsyncFocusHdl ), NULL, true);
+        pWindow->ImplGetWindowImpl()->mpFrameData->mnFocusId = Application::PostUserEvent( LINK( pWindow, vcl::Window, ImplAsyncFocusHdl ), nullptr, true);
         vcl::Window* pFocusWin = pWindow->ImplGetWindowImpl()->mpFrameData->mpFocusWin;
         if ( pFocusWin && pFocusWin->ImplGetWindowImpl()->mpCursor )
             pFocusWin->ImplGetWindowImpl()->mpCursor->ImplShow();
@@ -1914,7 +1914,7 @@ static void ImplHandleLoseFocus( vcl::Window* pWindow )
     if ( !pWindow->ImplGetWindowImpl()->mpFrameData->mnFocusId )
     {
         pWindow->ImplGetWindowImpl()->mpFrameData->mbStartFocusState = !pWindow->ImplGetWindowImpl()->mpFrameData->mbHasFocus;
-        pWindow->ImplGetWindowImpl()->mpFrameData->mnFocusId = Application::PostUserEvent( LINK( pWindow, vcl::Window, ImplAsyncFocusHdl ), NULL, true );
+        pWindow->ImplGetWindowImpl()->mpFrameData->mnFocusId = Application::PostUserEvent( LINK( pWindow, vcl::Window, ImplAsyncFocusHdl ), nullptr, true );
     }
 
     vcl::Window* pFocusWin = pWindow->ImplGetWindowImpl()->mpFrameData->mpFocusWin;
@@ -2379,7 +2379,7 @@ bool ImplWindowFrameProc( vcl::Window* _pWindow, SalFrame* /*pFrame*/,
     // #119709# for some unknown reason it is possible to receive events (in this case key events)
     // although the corresponding VCL window must have been destroyed already
     // at least ImplGetWindowImpl() was NULL in these cases, so check this here
-    if( pWindow->ImplGetWindowImpl() == NULL )
+    if( pWindow->ImplGetWindowImpl() == nullptr )
         return false;
 
     switch ( nEvent )
diff --git a/vcl/source/window/wrkwin.cxx b/vcl/source/window/wrkwin.cxx
index 3881f15009d5..78dc4bb06e0d 100644
--- a/vcl/source/window/wrkwin.cxx
+++ b/vcl/source/window/wrkwin.cxx
@@ -50,7 +50,7 @@ void WorkWindow::ImplInit( vcl::Window* pParent, WinBits nStyle, SystemParentDat
         nFrameStyle |= BORDERWINDOW_STYLE_APP;
 
     VclPtrInstance<ImplBorderWindow> pBorderWin( pParent, pSystemParentData, nStyle, nFrameStyle );
-    Window::ImplInit( pBorderWin, nStyle & (WB_3DLOOK | WB_CLIPCHILDREN | WB_DIALOGCONTROL | WB_SYSTEMFLOATWIN), NULL );
+    Window::ImplInit( pBorderWin, nStyle & (WB_3DLOOK | WB_CLIPCHILDREN | WB_DIALOGCONTROL | WB_SYSTEMFLOATWIN), nullptr );
     pBorderWin->mpWindowImpl->mpClientWindow = this;
     pBorderWin->GetBorder( mpWindowImpl->mnLeftBorder, mpWindowImpl->mnTopBorder, mpWindowImpl->mnRightBorder, mpWindowImpl->mnBottomBorder );
     mpWindowImpl->mpBorderWindow  = pBorderWin;
@@ -108,7 +108,7 @@ WorkWindow::WorkWindow( SystemParentData* pParent ) :
 {
     ImplInitWorkWindowData();
     mbSysChild = true;
-    ImplInit( NULL, 0, pParent );
+    ImplInit( nullptr, 0, pParent );
 }
 
 WorkWindow::~WorkWindow()
@@ -121,7 +121,7 @@ void WorkWindow::dispose()
     ImplSVData* pSVData = ImplGetSVData();
     if ( pSVData->maWinData.mpAppWin == this )
     {
-        pSVData->maWinData.mpAppWin = NULL;
+        pSVData->maWinData.mpAppWin = nullptr;
         Application::Quit();
     }
     SystemWindow::dispose();