Use idle to update preview in print dlg

Otherwise UI blocks while the preview is being updated

Change-Id: I98c536b83a31e9ea3f72effc8a602ee190a81e68
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/103951
Tested-by: Jenkins
Reviewed-by: Samuel Mehrbrodt <Samuel.Mehrbrodt@cib.de>

1 files changed, 34 insertions, 14 deletions

diff --git a/vcl/source/window/printdlg.cxx b/vcl/source/window/printdlg.cxx
index e9d35f96dd72..d68b4decc335 100644
--- a/vcl/source/window/printdlg.cxx
+++ b/vcl/source/window/printdlg.cxx
@@ -578,6 +578,8 @@ PrintDialog::PrintDialog(weld::Window* i_pWindow, const std::shared_ptr<PrinterC
     , mbCollateAlwaysOff(false)
     , mbShowLayoutFrame( true )
     , mbSingleJobs( false )
+    , maUpdatePreviewIdle("Print Dialog Update Preview Idle")
+    , maUpdatePreviewNoCacheIdle("Print Dialog Update Preview (no cache) Idle")
 {
     // save printbutton text, gets exchanged occasionally with print to file
     maPrintText = mxOKButton->get_label();
@@ -651,6 +653,11 @@ PrintDialog::PrintDialog(weld::Window* i_pWindow, const std::shared_ptr<PrinterC
         maNupLandscapeSize = Size( aNupSize.Height(), aNupSize.Width() );
     }
 
+    maUpdatePreviewIdle.SetPriority(TaskPriority::POST_PAINT);
+    maUpdatePreviewIdle.SetInvokeHandler(LINK( this, PrintDialog, updatePreviewIdle));
+    maUpdatePreviewNoCacheIdle.SetPriority(TaskPriority::POST_PAINT);
+    maUpdatePreviewNoCacheIdle.SetInvokeHandler(LINK(this, PrintDialog, updatePreviewNoCacheIdle));
+
     initFromMultiPageSetup( maPController->getMultipage() );
 
     // setup optional UI options set by application
@@ -895,6 +902,16 @@ void PrintDialog::setPreviewText()
     mxNumPagesText->set_label( aNewText );
 }
 
+IMPL_LINK_NOARG(PrintDialog, updatePreviewIdle, Timer*, void)
+{
+    preparePreview(true);
+}
+
+IMPL_LINK_NOARG(PrintDialog, updatePreviewNoCacheIdle, Timer*, void)
+{
+    preparePreview(false);
+}
+
 void PrintDialog::preparePreview( bool i_bMayUseCache )
 {
     VclPtr<Printer> aPrt( maPController->getPrinter() );
@@ -1138,7 +1155,10 @@ void PrintDialog::updateNup( bool i_bMayUseCache )
 
     mxNupOrder->setValues( aMPS.nOrder, nCols, nRows );
 
-    preparePreview( i_bMayUseCache );
+    if (i_bMayUseCache)
+        maUpdatePreviewIdle.Start();
+    else
+        maUpdatePreviewNoCacheIdle.Start();
 }
 
 void PrintDialog::updateNupFromPages( bool i_bMayUseCache )
@@ -1794,7 +1814,7 @@ IMPL_LINK(PrintDialog, ClickHdl, weld::Button&, rButton, void)
     }
     else if ( &rButton == mxPreviewBox.get() )
     {
-        preparePreview( true );
+        maUpdatePreviewIdle.Start();
     }
     else if( &rButton == mxForwardBtn.get() )
     {
@@ -1823,7 +1843,7 @@ IMPL_LINK(PrintDialog, ClickHdl, weld::Button&, rButton, void)
             checkOptionalControlDependencies();
 
             // update preview and page settings
-            preparePreview(false);
+            maUpdatePreviewNoCacheIdle.Start();
         }
         if( mxBrochureBtn->get_active() )
         {
@@ -1854,7 +1874,7 @@ IMPL_LINK(PrintDialog, ClickHdl, weld::Button&, rButton, void)
         maPController->setReversePrint( bChecked );
         maPController->setValue( "PrintReverse",
                                  makeAny( bChecked ) );
-        preparePreview( true );
+        maUpdatePreviewIdle.Start();
     }
     else if( &rButton == mxBorderCB.get() )
     {
@@ -1894,7 +1914,7 @@ IMPL_LINK(PrintDialog, ClickHdl, weld::Button&, rButton, void)
             setupPaperSidesBox();
 
             // tdf#63905 don't use cache: page size may change
-            preparePreview(false);
+            maUpdatePreviewNoCacheIdle.Start();
         }
         checkControlDependencies();
     }
@@ -1918,7 +1938,7 @@ IMPL_LINK( PrintDialog, SelectHdl, weld::ComboBox&, rBox, void )
             mxOKButton->set_label(maPrintText);
             updatePrinterText();
             setPaperSizes();
-            preparePreview(true);
+            maUpdatePreviewIdle.Start();
         }
         else // print to file
         {
@@ -1929,7 +1949,7 @@ IMPL_LINK( PrintDialog, SelectHdl, weld::ComboBox&, rBox, void )
 
             setPaperSizes();
             updateOrientationBox();
-            preparePreview( true );
+            maUpdatePreviewIdle.Start();
         }
 
         setupPaperSidesBox();
@@ -1973,7 +1993,7 @@ IMPL_LINK( PrintDialog, SelectHdl, weld::ComboBox&, rBox, void )
         checkPaperSize( aPaperSize );
         maPController->setPaperSizeFromUser( aPaperSize );
 
-        preparePreview(true);
+        maUpdatePreviewIdle.Start();
     }
 }
 
@@ -2005,7 +2025,7 @@ IMPL_LINK_NOARG(PrintDialog, ActivateHdl, weld::Entry&, bool)
     if (nNewCurPage != mnCurPage)
     {
         mnCurPage = nNewCurPage;
-        preparePreview(true);
+        maUpdatePreviewIdle.Start();
     }
     return true;
 }
@@ -2039,7 +2059,7 @@ IMPL_LINK( PrintDialog, UIOption_CheckHdl, weld::ToggleButton&, i_rBox, void )
         checkOptionalControlDependencies();
 
         // update preview and page settings
-        preparePreview(false);
+        maUpdatePreviewNoCacheIdle.Start();
     }
 }
 
@@ -2070,7 +2090,7 @@ IMPL_LINK( PrintDialog, UIOption_RadioHdl, weld::ToggleButton&, i_rBtn, void )
         mxPageRangeEdit->grab_focus();
 
     // update preview and page settings
-    preparePreview(false);
+    maUpdatePreviewNoCacheIdle.Start();
 }
 
 IMPL_LINK( PrintDialog, UIOption_SelectHdl, weld::ComboBox&, i_rBox, void )
@@ -2095,7 +2115,7 @@ IMPL_LINK( PrintDialog, UIOption_SelectHdl, weld::ComboBox&, i_rBox, void )
     checkOptionalControlDependencies();
 
     // update preview and page settings
-    preparePreview(false);
+    maUpdatePreviewNoCacheIdle.Start();
 }
 
 IMPL_LINK( PrintDialog, UIOption_SpinModifyHdl, weld::SpinButton&, i_rBox, void )
@@ -2111,7 +2131,7 @@ IMPL_LINK( PrintDialog, UIOption_SpinModifyHdl, weld::SpinButton&, i_rBox, void
         checkOptionalControlDependencies();
 
         // update preview and page settings
-        preparePreview(false);
+        maUpdatePreviewNoCacheIdle.Start();
     }
 }
 
@@ -2128,7 +2148,7 @@ IMPL_LINK( PrintDialog, UIOption_EntryModifyHdl, weld::Entry&, i_rBox, void )
         checkOptionalControlDependencies();
 
         // update preview and page settings
-        preparePreview(false);
+        maUpdatePreviewNoCacheIdle.Start();
     }
 }