diff --git a/lcl/interfaces/qt/qtobjects.pas b/lcl/interfaces/qt/qtobjects.pas
index aa8a0dd85e..6758479a76 100644
--- a/lcl/interfaces/qt/qtobjects.pas
+++ b/lcl/interfaces/qt/qtobjects.pas
@@ -284,19 +284,31 @@ type
   { TQtPixmap }
 
   TQtPixmap = class(TObject)
-  private
-  public
-    Handle: QPixmapH;
+  protected
+    FHandle: QPixmapH;
   public
     constructor Create(p1: PSize); virtual;
     destructor Destroy; override;
   public
-    procedure grabWindow(p1: Cardinal; x: Integer = 0; y: Integer = 0; w: Integer = -1; h: Integer = -1);
+    property Handle: QPixmapH read FHandle;
 
+    procedure grabWindow(p1: Cardinal; x: Integer = 0; y: Integer = 0; w: Integer = -1; h: Integer = -1);
     procedure toImage(retval: QImageH);
     class procedure fromImage(retval: QPixmapH; image: QImageH; flags: QtImageConversionFlags = QtAutoColor);
   end;
   
+  { TQtIcon }
+
+  TQtIcon = class(TObject)
+  protected
+    FHandle: QIconH;
+  public
+    constructor Create;
+    destructor Destroy; override;
+  public
+    property Handle: QIconH read FHandle;
+  end;
+  
   { TQtSystemTrayIcon }
 
   TQtSystemTrayIcon = class(TObject)
@@ -1743,24 +1755,25 @@ end;
 
 constructor TQtPixmap.Create(p1: PSize);
 begin
-  Handle := QPixmap_create(p1);
+  FHandle := QPixmap_create(p1);
 end;
 
 destructor TQtPixmap.Destroy;
 begin
-  if handle <> nil then QPixmap_destroy(handle);
+  if FHandle <> nil then
+    QPixmap_destroy(FHandle);
 
   inherited Destroy;
 end;
 
 procedure TQtPixmap.grabWindow(p1: Cardinal; x: Integer; y: Integer; w: Integer; h: Integer);
 begin
-  QPixmap_grabWindow(Handle, p1, x, y, w, h);
+  QPixmap_grabWindow(FHandle, p1, x, y, w, h);
 end;
 
 procedure TQtPixmap.toImage(retval: QImageH);
 begin
-  QPixmap_toImage(Handle, retval);
+  QPixmap_toImage(FHandle, retval);
 end;
 
 class procedure TQtPixmap.fromImage(retval: QPixmapH; image: QImageH; flags: QtImageConversionFlags = QtAutoColor);
@@ -2104,5 +2117,20 @@ begin
   end;
 end;
 
+{ TQtIcon }
+
+constructor TQtIcon.Create;
+begin
+  FHandle := QIcon_create();
+end;
+
+destructor TQtIcon.Destroy;
+begin
+  if FHandle <> nil then
+    QIcon_destroy(FHandle);
+    
+  inherited Destroy;
+end;
+
 end.
 
diff --git a/lcl/interfaces/qt/qtwidgets.pas b/lcl/interfaces/qt/qtwidgets.pas
index 40a9ea02cc..b43ee01054 100644
--- a/lcl/interfaces/qt/qtwidgets.pas
+++ b/lcl/interfaces/qt/qtwidgets.pas
@@ -95,9 +95,6 @@ type
     procedure Activate;
     procedure BringToFront;
     procedure OffsetMousePos(APoint: PQtPoint); virtual;
-    procedure SetColor(const Value: PQColor); virtual;
-    procedure SetTextColor(const Value: PQColor); virtual;
-    procedure SetCursor(const ACursor: QCursorH); virtual;
     procedure Update(ARect: PRect = nil);
     procedure Repaint(ARect: PRect = nil);
     procedure setWindowTitle(Str: PWideString);
@@ -115,17 +112,23 @@ type
     procedure grabMouse;
     function hasFocus: Boolean;
     procedure releaseMouse;
+    procedure setColor(const Value: PQColor); virtual;
+    procedure setCursor(const ACursor: QCursorH); virtual;
     procedure setEnabled(p1: Boolean);
     procedure setGeometry(ARect: TRect); overload;
-    procedure setVisible(visible: Boolean); virtual;
-    procedure setWindowModality(windowModality: QtWindowModality);
+    procedure setMaximumSize(AWidth, AHeight: Integer);
+    procedure setMinimumSize(AWidth, AHeight: Integer);
     procedure setParent(parent: QWidgetH); virtual;
+    procedure setTextColor(const Value: PQColor); virtual;
+    procedure setVisible(visible: Boolean); virtual;
     procedure setWindowFlags(_type: QtWindowFlags);
-    function windowFlags: QtWindowFlags;
+    procedure setWindowIcon(AIcon: QIconH);
+    procedure setWindowModality(windowModality: QtWindowModality);
     procedure setWidth(p1: Integer);
     procedure setHeight(p1: Integer);
     procedure setTabOrder(p1, p2: TQtWidget);
     procedure setWindowState(AState: QtWindowStates);
+    function windowFlags: QtWindowFlags;
     function windowModality: QtWindowModality;
 
     property Props[AnIndex:String]:pointer read GetProps write SetProps;
@@ -1832,6 +1835,16 @@ begin
   QWidget_setGeometry(Widget, @ARect);
 end;
 
+procedure TQtWidget.setMaximumSize(AWidth, AHeight: Integer);
+begin
+  QWidget_setMaximumSize(Widget, AWidth, AHeight);
+end;
+
+procedure TQtWidget.setMinimumSize(AWidth, AHeight: Integer);
+begin
+  QWidget_setMinimumSize(Widget, AWidth, AHeight);
+end;
+
 procedure TQtWidget.setVisible(visible: Boolean);
 begin
   QWidget_setVisible(Widget, visible);
@@ -1857,6 +1870,11 @@ begin
   QWidget_setWindowFlags(Widget, _type);
 end;
 
+procedure TQtWidget.setWindowIcon(AIcon: QIconH);
+begin
+  QWidget_setWindowIcon(Widget, AIcon);
+end;
+
 function TQtWidget.windowFlags: QtWindowFlags;
 begin
   Result := QWidget_windowFlags(Widget);
diff --git a/lcl/interfaces/qt/qtwscontrols.pp b/lcl/interfaces/qt/qtwscontrols.pp
index c817d6a782..dce0dfbfbe 100644
--- a/lcl/interfaces/qt/qtwscontrols.pp
+++ b/lcl/interfaces/qt/qtwscontrols.pp
@@ -94,7 +94,7 @@ type
                                       const AOldPos, ANewPos: Integer;
                                       const AChildren: TFPList); override;}
 
-    //class procedure ConstraintsChange(const AWinControl: TWinControl); override;
+    class procedure ConstraintsChange(const AWinControl: TWinControl); override;
   end;
 
   { TQtWSGraphicControl }
@@ -334,6 +334,18 @@ begin
   end;
 end;
 
+class procedure TQtWSWinControl.ConstraintsChange(const AWinControl: TWinControl);
+var
+  Widget: TQtWidget;
+begin
+  Widget := TQtWidget(AWinControl.Handle);
+  with AWinControl do
+  begin
+    Widget.setMinimumSize(Constraints.MinWidth, Constraints.MinHeight);
+    Widget.setMaximumSize(Constraints.MaxWidth, Constraints.MaxHeight);
+  end;
+end;
+
 {------------------------------------------------------------------------------
   Method: TQtWSWinControl.SetBounds
   Params:  AWinControl - the calling object