qt: more safe deletion of gdi objects, and first of all brush

git-svn-id: trunk@15155 -

lcl/interfaces/qt/qtobject.inc

@@ -437,11 +437,19 @@ begin
   if GDIObject = 0 then Exit;
   
   aObject := TObject(GDIObject);
-
-  if aObject is TObject then
-  begin
-    Result := (aObject is TQtFont) or (aObject is TQtBrush) or (aObject is TQtImage)
-      or (aObject is TQtPen) or (aObject is TQTRegion);
+  try
+    if aObject is TObject then
+    begin
+      Result :=
+        (aObject is TQtFont) or
+        (aObject is TQtBrush) or
+        (aObject is TQtImage) or
+        (aObject is TQtPen) or
+        (aObject is TQTRegion);
+    end;
+  except
+    DebugLn(['Gdi object: ', GDIObject, ' is not an object!']);
+    raise;
   end;
 end;
 

lcl/interfaces/qt/qtobjects.pas

@@ -71,6 +71,7 @@ type
   public
     Owner: TObject;
     FShared: Boolean;
+    FSelected: Boolean;
   end;
 
   { TQtAction }
@@ -254,6 +255,7 @@ type
   private
     FPenPos: TQtPoint;
     FOwnPainter: Boolean;
+    FInDestroyObjects: Boolean;
     SelFont: TQTFont;
     SelBrush: TQTBrush;
     SelPen: TQtPen;
@@ -1256,9 +1258,11 @@ begin
     WriteLn('TQtBrush.Create CreateHandle: ', dbgs(CreateHandle));
   {$endif}
 
-  if CreateHandle then Widget := QBrush_create;
+  if CreateHandle then
+    Widget := QBrush_create;
   
   FShared := AShared;
+  FSelected := False;
 end;
 
 {------------------------------------------------------------------------------
@@ -1272,7 +1276,7 @@ begin
     WriteLn('TQtBrush.Destroy');
   {$endif}
 
-  if not FShared and (Widget <> nil) then
+  if not FShared and (Widget <> nil) and not FSelected then
     QBrush_destroy(Widget);
 
   inherited Destroy;
@@ -1605,6 +1609,8 @@ end;
 
 procedure TQtDeviceContext.CreateObjects;
 begin
+  FInDestroyObjects := False;
+
   vFont := TQtFont.Create(False);
   vFont.Owner := Self;
 
@@ -1625,16 +1631,21 @@ end;
 
 procedure TQtDeviceContext.DestroyObjects;
 begin
+  if FInDestroyObjects then
+    Exit;
+  FInDestroyObjects := True;
   vFont.Widget := nil;
-  vFont.Free;
+  FreeAndNil(vFont);
+  //WriteLn('Destroying brush: ', PtrUInt(vBrush), ' ', ClassName, ' ', PtrUInt(Self));
   vBrush.Widget := nil;
-  vBrush.Free;
+  FreeAndNil(vBrush);
   vPen.Widget := nil;
-  vPen.Free;
+  FreeAndNil(vPen);
   vRegion.Widget := nil;
-  vRegion.Free;
+  FreeAndNil(vRegion);
   vBackgroundBrush.Widget := nil;
-  vBackgroundBrush.Free;
+  FreeAndNil(vBackgroundBrush);
+  FInDestroyObjects := False;
 end;
 
 {------------------------------------------------------------------------------
@@ -2082,7 +2093,7 @@ begin
   if vBrush <> nil then
     vBrush.Widget := QPainter_brush(Widget);
     
-  if SelBrush=nil then
+  if SelBrush = nil then
     Result := vBrush
   else
     Result := SelBrush;
@@ -2098,7 +2109,12 @@ begin
   {$ifdef VerboseQt}
   Write('TQtDeviceContext.setBrush() ');
   {$endif}
+  if SelBrush <> nil then
+    SelBrush.FSelected := False;
   SelBrush := ABrush;
+  if SelBrush <> nil then
+    SelBrush.FSelected := True;
+    
   if (ABrush.Widget <> nil) and (Widget <> nil) then
     QPainter_setBrush(Widget, ABrush.Widget);
 end;

lcl/interfaces/qt/qtwidgets.pas

@@ -8203,9 +8203,12 @@ end;
 
 procedure TQtDesignWidget.DestroyWidget;
 begin
-  removeProperty(FDesignControl, 'lclwidget');
-  QObject_deleteLater(FDesignControl);
-  FDesignControl := nil;
+  if FDesignControl <> nil then
+  begin
+    removeProperty(FDesignControl, 'lclwidget');
+    QObject_deleteLater(FDesignControl);
+    FDesignControl := nil;
+  end;
   inherited DestroyWidget;
 end;
 
@@ -8217,6 +8220,7 @@ begin
   {$ifdef VerboseQt}
     WriteLn('TQtWidget.SlotPaint ', dbgsName(LCLObject));
   {$endif}
+
   if (LCLObject is TWinControl) then
   begin
     FillChar(Msg, SizeOf(Msg), #0);
@@ -8329,14 +8333,18 @@ var
   Method: TMethod;
 begin
   inherited AttachEvents;
-  FDesignControlEventHook := QObject_hook_create(FDesignControl);
-  TEventFilterMethod(Method) := @DesignControlEventFilter;
-  QObject_hook_hook_events(FDesignControlEventHook, Method);
+  if FDesignControl <> nil then
+  begin
+    FDesignControlEventHook := QObject_hook_create(FDesignControl);
+    TEventFilterMethod(Method) := @DesignControlEventFilter;
+    QObject_hook_hook_events(FDesignControlEventHook, Method);
+  end;
 end;
 
 procedure TQtDesignWidget.DetachEvents;
 begin
-  QObject_hook_destroy(FDesignControlEventHook);
+  if FDesignControlEventHook <> nil then
+    QObject_hook_destroy(FDesignControlEventHook);
   inherited DetachEvents;
 end;
 

lcl/interfaces/qt/qtwinapi.inc

@@ -382,7 +382,7 @@ begin
       [LogBrush.lbStyle, LogBrush.lbColor, ColorToString(LogBrush.lbColor)]));
   {$endif}
 
-  result := 0;
+  Result := 0;
 
   QtBrush := TQtBrush.Create(True);
 
@@ -429,7 +429,7 @@ begin
         QtBrush.setTextureImage(TQtImage(LogBrush.lbHatch).Handle);
       end;
     else
-      WriteLn(Format('Unsupported Style %d',[LogBrush.lbStyle]));
+      DebugLn(Format('Unsupported Style %d',[LogBrush.lbStyle]));
     end;
 
     {
@@ -457,6 +457,7 @@ begin
   end;
 
   Result := HBRUSH(QtBrush);
+  //WriteLn('Created brush ', Result);
 
   {$ifdef VerboseQtWinAPI}
     WriteLn('Trace:< [WinAPI CreateBrushIndirect] Result: ', dbghex(Result));
@@ -837,15 +838,18 @@ begin
   end;
 
   if AObject is TQtResource then
-    if TQtResource(AObject).Owner<>nil then
+    if TQtResource(AObject).Owner <> nil then
     begin
       // this is an owned (default) resource, let owner free it
       DebugLn('WARNING: Trying to Free a default resource');
-      AObject:=nil;
+      AObject := nil;
     end;
   
   if AObject <> nil then
+  begin
+    //WriteLn('Delete object: ', PtrUInt(AObject));
     AObject.Free;
+  end;
   
   // Find out if we want to release internal GDI object
 {    case GDIType of