tdf#123406 KDE5: Update delayed frame destruction

Move deleteLater() call to the different event loop.
This fixes issue with frames not being disposed of
deterministically, and previously opened window
not reactivating.

Also hide modal dialog window before unsetting modal mode.
Unsetting modal mode may require to toggle window visibility.
Window will be hidden soon anyway,
and additional generated events might make finding correct
focused window harder.

Change-Id: Id7839f817075785287b09f6ac79eb3fb211726aa
Reviewed-on: https://gerrit.libreoffice.org/68852
Tested-by: Jenkins
Reviewed-by: Katarina Behrens <Katarina.Behrens@cib.de>

3 files changed, 14 insertions, 4 deletions

diff --git a/vcl/inc/qt5/Qt5Instance.hxx b/vcl/inc/qt5/Qt5Instance.hxx
index 38ead9ed9036..52153846faa1 100644
--- a/vcl/inc/qt5/Qt5Instance.hxx
+++ b/vcl/inc/qt5/Qt5Instance.hxx
@@ -53,10 +53,12 @@ public:
 private Q_SLOTS:
     bool ImplYield(bool bWait, bool bHandleAllCurrentEvents);
     void ImplRunInMain();
+    static void deleteObjectLater(QObject* pObject);
 
 Q_SIGNALS:
     bool ImplYieldSignal(bool bWait, bool bHandleAllCurrentEvents);
     void ImplRunInMainSignal();
+    void deleteObjectLaterSignal(QObject* pObject);
 
 public:
     explicit Qt5Instance(bool bUseCairo = false);
diff --git a/vcl/qt5/Qt5Instance.cxx b/vcl/qt5/Qt5Instance.cxx
index 4527aaae5ebc..05ebf9aafb1b 100644
--- a/vcl/qt5/Qt5Instance.cxx
+++ b/vcl/qt5/Qt5Instance.cxx
@@ -219,6 +219,12 @@ Qt5Instance::Qt5Instance(bool bUseCairo)
             Qt::BlockingQueuedConnection);
     connect(this, &Qt5Instance::ImplRunInMainSignal, this, &Qt5Instance::ImplRunInMain,
             Qt::QueuedConnection); // no Blocking!
+
+    // this one needs to be queued non-blocking
+    // in order to have this event arriving to correct event processing loop
+    connect(this, &Qt5Instance::deleteObjectLaterSignal, this,
+            [](QObject* pObject) { Qt5Instance::deleteObjectLater(pObject); },
+            Qt::QueuedConnection);
 }
 
 Qt5Instance::~Qt5Instance()
@@ -230,6 +236,8 @@ Qt5Instance::~Qt5Instance()
         free(m_pFakeArgvFreeable[i]);
 }
 
+void Qt5Instance::deleteObjectLater(QObject* pObject) { pObject->deleteLater(); }
+
 SalFrame* Qt5Instance::CreateChildFrame(SystemParentData* /*pParent*/, SalFrameStyleFlags nStyle)
 {
     return new Qt5Frame(nullptr, nStyle, m_bUseCairo);
@@ -246,7 +254,7 @@ void Qt5Instance::DestroyFrame(SalFrame* pFrame)
     if (pFrame)
     {
         assert(dynamic_cast<Qt5Frame*>(pFrame));
-        static_cast<Qt5Frame*>(pFrame)->deleteLater();
+        Q_EMIT deleteObjectLaterSignal(static_cast<Qt5Frame*>(pFrame));
     }
 }
 
@@ -261,7 +269,7 @@ void Qt5Instance::DestroyObject(SalObject* pObject)
     if (pObject)
     {
         assert(dynamic_cast<Qt5Object*>(pObject));
-        static_cast<Qt5Object*>(pObject)->deleteLater();
+        Q_EMIT deleteObjectLaterSignal(static_cast<Qt5Object*>(pObject));
     }
 }
 
diff --git a/vcl/source/window/dialog.cxx b/vcl/source/window/dialog.cxx
index 219cf1416237..6f755e4139fb 100644
--- a/vcl/source/window/dialog.cxx
+++ b/vcl/source/window/dialog.cxx
@@ -1098,6 +1098,8 @@ void Dialog::EndDialog( long nResult )
 
     const bool bModal = GetType() != WindowType::MODELESSDIALOG;
 
+    Hide();
+
     if (bModal)
     {
         SetModalInputMode(false);
@@ -1122,8 +1124,6 @@ void Dialog::EndDialog( long nResult )
         }
     }
 
-    Hide();
-
     if (bModal && GetParent())
     {
         NotifyEvent aNEvt( MouseNotifyEvent::ENDEXECUTEDIALOG, this );