{ $Id: qtwscontrols.pp 50535 2015-11-30 16:43:36Z zeljko $}
{
 *****************************************************************************
 *                              QtWSControls.pp                              * 
 *                              ---------------                              * 
 *                                                                           *
 *                                                                           *
 *****************************************************************************

 *****************************************************************************
  This file is part of the Lazarus Component Library (LCL)

  See the file COPYING.modifiedLGPL.txt, included in this distribution,
  for details about the license.
 *****************************************************************************
}
unit QtWSControls;

{$mode objfpc}{$H+}

interface

{$I qtdefines.inc}

uses
  // Bindings
  qt4,
  qtwidgets, qtobjects, qtproc, qtint,
  // LCL
  SysUtils, Classes, Types, Controls, LCLType, LazUTF8, Forms, Graphics,
  // Widgetset
  InterfaceBase, WSProc, WSControls, WSLCLClasses;

type

  { TQtWSDragImageList }

  TQtWSDragImageList = class(TWSDragImageList)
  published
    class function BeginDrag(const ADragImageList: TDragImageList; Window: HWND; AIndex, X, Y: Integer): Boolean; override;
    class function DragMove(const ADragImageList: TDragImageList; X, Y: Integer): Boolean; override;
    class procedure EndDrag(const ADragImageList: TDragImageList); override;
    class function HideDragImage(const ADragImageList: TDragImageList;
      ALockedWindow: HWND; DoUnLock: Boolean): Boolean; override;
    class function ShowDragImage(const ADragImageList: TDragImageList;
      ALockedWindow: HWND; X, Y: Integer; DoLock: Boolean): Boolean; override;
  end;

  { TQtWSControl }

  TQtWSControl = class(TWSControl)
  published
  end;

  { TQtWSWinControl }

  TQtWSWinControl = class(TWSWinControl)
  published
    class function  CanFocus(const AWinControl: TWinControl): Boolean; override;
    class function  CreateHandle(const AWinControl: TWinControl;
          const AParams: TCreateParams): TLCLIntfHandle; override;
    class procedure DestroyHandle(const AWinControl: TWinControl); override;
    class procedure Invalidate(const AWinControl: TWinControl); override;
    class procedure AddControl(const AControl: TControl); override;
    class function  GetClientBounds(const AWincontrol: TWinControl; var ARect: TRect): Boolean; override;
    class function  GetClientRect(const AWincontrol: TWinControl; var ARect: TRect): Boolean; override;
    class function GetDesignInteractive(const AWinControl: TWinControl; AClientPos: TPoint): Boolean; override;

    class procedure SetBiDiMode(const AWinControl: TWinControl; UseRightToLeftAlign, UseRightToLeftReading, UseRightToLeftScrollBar : Boolean); override;
    class procedure SetBounds(const AWinControl: TWinControl; const ALeft, ATop, AWidth, AHeight: Integer); override;
    class procedure SetBorderStyle(const AWinControl: TWinControl; const ABorderStyle: TBorderStyle); override;
    class procedure SetPos(const AWinControl: TWinControl; const ALeft, ATop: Integer); override;
    class procedure SetSize(const AWinControl: TWinControl; const AWidth, AHeight: Integer); override;
    class procedure ShowHide(const AWinControl: TWinControl); override; //TODO: rename to SetVisible(control, visible)
    class procedure SetColor(const AWinControl: TWinControl); override;
    class procedure SetCursor(const AWinControl: TWinControl; const ACursor: HCURSOR); override;
    class procedure SetFont(const AWinControl: TWinControl; const AFont: TFont); override;
    class procedure SetShape(const AWinControl: TWinControl; const AShape: HBITMAP); override;

    class procedure GetPreferredSize(const AWinControl: TWinControl;
      var PreferredWidth, PreferredHeight: integer; WithThemeSpace: Boolean); override;

    class function  GetText(const AWinControl: TWinControl; var AText: String): Boolean; override;
    class procedure SetText(const AWinControl: TWinControl; const AText: string); override;

    class procedure SetChildZPosition(const AWinControl, AChild: TWinControl;
                                      const AOldPos, ANewPos: Integer;
                                      const AChildren: TFPList); override;

    class procedure ConstraintsChange(const AWinControl: TWinControl); override;
    class procedure PaintTo(const AWinControl: TWinControl; ADC: HDC; X, Y: Integer); override;
    class procedure ScrollBy(const AWinControl: TWinControl; DeltaX, DeltaY: integer); override;
  end;

  { TQtWSGraphicControl }

  TQtWSGraphicControl = class(TWSGraphicControl)
  published
  end;

  { TQtWSCustomControl }

  TQtWSCustomControl = class(TWSCustomControl)
  published
    class function CreateHandle(const AWinControl: TWinControl;
          const AParams: TCreateParams): TLCLIntfHandle; override;
  end;

  { TQtWSImageList }

  TQtWSImageList = class(TWSImageList)
  published
  end;

const
  TBorderStyleToQtFrameShapeMap: array[TBorderStyle] of QFrameShape =
  (
 { bsNone   } QFrameNoFrame,
 { bsSingle } QFrameStyledPanel
  );
  TLayoutDirectionMap: array[Boolean] of QtLayoutDirection =
  (
 { False } QtLeftToRight,
 { True  } QtRightToLeft
  );
implementation
{$IF DEFINED(VerboseQtResize) OR DEFINED(VerboseQt)}
uses LCLProc;
{$ENDIF}

{------------------------------------------------------------------------------
  Method: TQtWSCustomControl.CreateHandle
  Params:  None
  Returns: Nothing
 ------------------------------------------------------------------------------}
class function TQtWSCustomControl.CreateHandle(const AWinControl: TWinControl;
          const AParams: TCreateParams): TLCLIntfHandle;
var
  QtCustomControl: TQtCustomControl;
begin
  {$ifdef VerboseQt}
    WriteLn('> TQtWSCustomControl.CreateHandle for ',dbgsname(AWinControl));
  {$endif}

  QtCustomControl := TQtCustomControl.Create(AWinControl, AParams);
  QtCustomControl.setFrameShape(TBorderStyleToQtFrameShapeMap[TCustomControl(AWinControl).BorderStyle]);
  QtCustomControl.viewportNeeded;
  QtCustomControl.verticalScrollBar;
  QtCustomControl.horizontalScrollBar;
  QtCustomControl.AttachEvents;
  Result := TLCLIntfHandle(QtCustomControl);

  {$ifdef VerboseQt}
    WriteLn('< TQtWSCustomControl.CreateHandle for ',dbgsname(AWinControl),' Result: ', dbgHex(Result));
  {$endif}
end;

{------------------------------------------------------------------------------
  Function: TQtWSWinControl.CanFocus
  Params:  TWinControl
  Returns: Boolean
 ------------------------------------------------------------------------------}
class function TQtWSWinControl.CanFocus(const AWinControl: TWinControl): Boolean;
var
  Widget: TQtWidget;
begin
  if AWinControl.HandleAllocated then
  begin
    Widget := TQtWidget(AWinControl.Handle);
    Result := (Widget.getFocusPolicy <> QtNoFocus);
  end else
    Result := False;
end;

{------------------------------------------------------------------------------
  Method: TQtWSWinControl.CreateHandle
  Params:  None
  Returns: Nothing
 ------------------------------------------------------------------------------}
class function TQtWSWinControl.CreateHandle(const AWinControl: TWinControl;
  const AParams: TCreateParams): TLCLIntfHandle;
var
  QtWidget: TQtWidget;
begin

  {$ifdef VerboseQt}
    WriteLn('> TQtWSWinControl.CreateHandle for ',dbgsname(AWinControl));
  {$endif}
  QtWidget := TQtWidget.Create(AWinControl, AParams);

  QtWidget.AttachEvents;

  // Finalization

  Result := TLCLIntfHandle(QtWidget);

  {$ifdef VerboseQt}
    WriteLn('< TQtWSWinControl.CreateHandle for ',dbgsname(AWinControl),' Result: ', dbgHex(Result));
  {$endif}
end;

{------------------------------------------------------------------------------
  Method: TQtWSWinControl.DestroyHandle
  Params:  None
  Returns: Nothing
 ------------------------------------------------------------------------------}
class procedure TQtWSWinControl.DestroyHandle(const AWinControl: TWinControl);
begin
  TQtWidget(AWinControl.Handle).Release;
end;

{------------------------------------------------------------------------------
  Method: TQtWSWinControl.Invalidate
  Params:  None
  Returns: Nothing
 ------------------------------------------------------------------------------}
class procedure TQtWSWinControl.Invalidate(const AWinControl: TWinControl);
begin
  if not WSCheckHandleAllocated(AWinControl, 'Invalidate') then
    Exit;

  TQtWidget(AWinControl.Handle).Update;
end;

class procedure TQtWSWinControl.AddControl(const AControl: TControl);
var
  Child: TQtWidget;
  Parent: TQtWidget;
begin
  if (AControl is TWinControl) and (TWinControl(AControl).HandleAllocated) then
  begin
    Child := TQtWidget(TWinControl(AControl).Handle);
    Parent := TQtWidget(AControl.Parent.Handle);
    if Child.getParent <> Parent.GetContainerWidget then
    begin
      Child.BeginUpdate;
      Child.setParent(Parent.GetContainerWidget);
      Child.EndUpdate;
    end;
  end;
end;

class function TQtWSWinControl.GetClientBounds(const AWincontrol: TWinControl;
  var ARect: TRect): Boolean;
begin
  Result := False;
  if not WSCheckHandleAllocated(AWinControl, 'GetClientBounds') then
    Exit;

  ARect := TQtWidget(AWinControl.Handle).getClientBounds;
  Result := True;
end;

class function TQtWSWinControl.GetClientRect(const AWincontrol: TWinControl;
  var ARect: TRect): Boolean;
begin
  Result := False;
  if not WSCheckHandleAllocated(AWinControl, 'GetClientRect') then
    Exit;
    
  ARect := TQtWidget(AWinControl.Handle).getClientBounds;
  OffsetRect(ARect, -ARect.Left, -ARect.Top);
  Result := True;
end;

class function TQtWSWinControl.GetDesignInteractive(
  const AWinControl: TWinControl; AClientPos: TPoint): Boolean;
begin
  Result := False;
  if not WSCheckHandleAllocated(AWinControl, 'GetDesignInteractive') then
    Exit;
end;

class procedure TQtWSWinControl.SetBiDiMode(const AWinControl : TWinControl;
  UseRightToLeftAlign, UseRightToLeftReading, UseRightToLeftScrollBar : Boolean
  );
begin
  if not WSCheckHandleAllocated(AWinControl, 'SetBiDiMode') then
    Exit;

  TQtWidget(AWinControl.Handle).setLayoutDirection(TLayoutDirectionMap[UseRightToLeftAlign]);
end;

class procedure TQtWSWinControl.GetPreferredSize(const AWinControl: TWinControl;
  var PreferredWidth, PreferredHeight: integer; WithThemeSpace: Boolean);
begin
  Assert(AWinControl.HandleAllocated, 'GetPreferredSize: Handle not allocated');
  TQtWidget(AWinControl.Handle).PreferredSize(PreferredWidth, PreferredHeight, WithThemeSpace);
end;

class function TQtWSWinControl.GetText(const AWinControl: TWinControl;
  var AText: String): Boolean;
begin
  Result := False;
  if not WSCheckHandleAllocated(AWincontrol, 'GetText') then
    Exit;

  Result := not TQtWidget(AWinControl.Handle).getTextStatic;
  if Result then
    AText := UTF16ToUTF8(TQtWidget(AWinControl.Handle).getText);
end;

class procedure TQtWSWinControl.SetText(const AWinControl: TWinControl;
  const AText: string);
begin
  if not WSCheckHandleAllocated(AWincontrol, 'SetText') then
    Exit;
  TQtWidget(AWinControl.Handle).BeginUpdate;
  TQtWidget(AWinControl.Handle).setText(GetUtf8String(AText));
  TQtWidget(AWinControl.Handle).EndUpdate;
end;

class procedure TQtWSWinControl.SetChildZPosition(const AWinControl,
                AChild: TWinControl; const AOldPos, ANewPos: Integer; const AChildren: TFPList);
var
  n: Integer;
  Child: TWinControl;
  Reorder: TFPList;
begin
  if not WSCheckHandleAllocated(AWincontrol, 'SetChildZPosition') then
    Exit;
  if not WSCheckHandleAllocated(AChild, 'SetChildZPosition (child)') then
    Exit;

  if (ANewPos <= 0) or (ANewPos >= AChildren.Count - 1) then
  begin
    // simple
    if ANewPos <= 0 then // bottom
      TQtWidget(AChild.Handle).lowerWidget
    else
      TQtWidget(AChild.Handle).raiseWidget;
  end else
  begin
    if (ANewPos >= 0) and (ANewPos < AChildren.Count -1) then
    begin
      Reorder := TFPList.Create;
      for n := AChildren.Count - 1 downto 0 do
        Reorder.Add(AChildren[n]);
      Child := TWinControl(Reorder[ANewPos + 1]);
      if Child.HandleAllocated then
        TQtWidget(AChild.Handle).stackUnder(TQtWidget(Child.Handle).Widget)
      else
        TQtWidget(AChild.Handle).lowerWidget;
      Reorder.Free;
    end;
  end;
end;

class procedure TQtWSWinControl.ConstraintsChange(const AWinControl: TWinControl);
const
  QtMaxContraint = $FFFFFF;
var
  Widget: TQtWidget;
  MW, MH: Integer;
begin
  if not WSCheckHandleAllocated(AWincontrol, 'ConstraintsChange') then
    Exit;
    
  Widget := TQtWidget(AWinControl.Handle);
  with AWinControl do
  begin
    MW := Constraints.MinWidth;
    MH := Constraints.MinHeight;

    if MW < QtMinimumWidgetSize then
      MW := 0;
    if MH < QtMinimumWidgetSize then
      MH := 0;

    Widget.setMinimumSize(MW, MH);

    if Constraints.MaxWidth = 0 then
      MW := QtMaxContraint
    else
      MW := Constraints.MaxWidth;
    if Constraints.MaxHeight = 0 then
      MH := QtMaxContraint
    else
      MH := Constraints.MaxHeight;
    Widget.setMaximumSize(MW, MH);
  end;
end;

class procedure TQtWSWinControl.PaintTo(const AWinControl: TWinControl;
  ADC: HDC; X, Y: Integer);
var
  Context: TQtDeviceContext absolute ADC;
  Widget: TQtWidget;
  Window: TQtMainWindow;
  Pixmap: TQtPixmap;
  DCSize: TSize;
  APoint: TQtPoint;
  ARect, GRect: TRect;
  OffsetY: Integer;
  NewHandle: QPixmapH;
begin
  if not WSCheckHandleAllocated(AWincontrol, 'PaintTo') or (ADC = 0) then
    Exit;

  Widget := TQtWidget(AWinControl.Handle);
  ARect := Widget.getFrameGeometry;
  GRect := Widget.getGeometry;

  // calculate OffsetY only in case when we are form
  if (AWinControl.FCompStyle = csForm) and Assigned(TCustomForm(AWinControl).Menu) then
  begin
    Window := TQtMainWindow(TCustomForm(AWinControl).Handle);
    if Window.MenuBar.getVisible then
      OffsetY := Window.MenuBar.getHeight;
  end else
    OffsetY := 0;

  with DCSize, ARect do
  begin
    cx := Right - Left;
    cy := Bottom - Top;
  end;
  Pixmap := TQtPixmap.Create(@DCSize);
  try
    OffsetRect(GRect, -ARect.Left, -ARect.Top);
    Pixmap.grabWidget(Widget.Widget, 0, 0);

    // apply offset if we have main menu
    APoint := QtPoint(X, Y + OffsetY);
    ARect := Rect(0, 0, Pixmap.getWidth, Pixmap.getHeight);
    // also scale pixmap by height of menu, so it's catched in our image.
    if OffsetY <> 0 then
    begin
      NewHandle := QPixmap_create();
      QPixmap_scaled(Pixmap.Handle, NewHandle, Pixmap.GetWidth, Pixmap.GetHeight - OffsetY);
      Context.drawPixmap(@APoint, NewHandle, @ARect);
      QPixmap_destroy(NewHandle);
    end else
      Context.drawPixmap(@APoint, Pixmap.Handle, @ARect);
  finally
    Pixmap.Free;
  end;
end;

class procedure TQtWSWinControl.ScrollBy(const AWinControl: TWinControl;
  DeltaX, DeltaY: integer);
var
  Widget: TQtCustomControl;
  ABar: TQtScrollBar;
  APosition: Integer;
begin
  if not WSCheckHandleAllocated(AWinControl, 'ScrollBy') then
    Exit;
  if TQtWidget(AWinControl.Handle) is TQtCustomControl then
  begin
    Widget := TQtCustomControl(AWinControl.Handle);
    Widget.viewport.scroll(DeltaX, DeltaY);
  end else
  if TQtWidget(AWinControl.Handle) is TQtAbstractScrollArea then
  begin
    ABar := TQtAbstractScrollArea(AWinControl.Handle).horizontalScrollBar;
    if ABar = nil then
      exit;
    if ABar.getTracking then
      APosition := ABar.getSliderPosition
    else
      APosition := ABar.getValue;
    if DeltaX <> 0 then
    begin
      APosition += -DeltaX;
      if ABar.getTracking then
        ABar.setSliderPosition(APosition)
      else
        ABar.setValue(APosition);
    end;
    ABar := TQtAbstractScrollArea(AWinControl.Handle).verticalScrollBar;
    if ABar = nil then
      exit;
    if ABar.getTracking then
      APosition := ABar.getSliderPosition
    else
      APosition := ABar.getValue;
    if DeltaY <> 0 then
    begin
      APosition += -DeltaY;
      if ABar.getTracking then
        ABar.setSliderPosition(APosition)
      else
        ABar.setValue(APosition);
    end;
  end
  {$IFDEF VerboseQt}
  else
    DebugLn(Format('WARNING: TQtWSWinControl.ScrollBy(): Qt widget handle %s is not TQtCustomControl',[DbgSName(TQtWidget(AWinControl.Handle))]));
  {$ENDIF}
end;

{------------------------------------------------------------------------------
  Method: TQtWSWinControl.SetBounds
  Params:  AWinControl - the calling object
           ALeft, ATop - Position
           AWidth, AHeight - Size
  Returns: Nothing

  Sets the position and size of a widget
 ------------------------------------------------------------------------------}
class procedure TQtWSWinControl.SetBounds(const AWinControl: TWinControl;
  const ALeft, ATop, AWidth, AHeight: Integer);
var
  R: TRect;
  Box: TQtWidget;
  AForm: TCustomForm;
begin
  if not WSCheckHandleAllocated(AWincontrol, 'SetBounds') then
    Exit;
  R := Rect(ALeft, ATop, AWidth, AHeight);

  Box := nil;
  if Assigned(AWinControl.Parent) and
    AWinControl.Parent.HandleAllocated then
      Box := TQtWidget(AWinControl.Parent.Handle);

  if Assigned(Box) and
    (Box.ChildOfComplexWidget = ccwScrollingWinControl) then
  begin
    R := Rect(ALeft - TQtCustomControl(Box).horizontalScrollBar.getValue,
      ATop - TQtCustomControl(Box).verticalScrollBar.getValue, AWidth, AHeight);
  end;

  {$IFDEF QTSCROLLABLEFORMS}
  if Assigned(AWinControl.Parent) and
    (AWinControl.Parent.FCompStyle = csForm) then
  begin
    AForm := TCustomForm(AWinControl.Parent);
    if Assigned(TQtMainWindow(AForm.Handle).ScrollArea) then
    begin
      Box := TQtMainWindow(AForm.Handle).ScrollArea;
      R := Rect(ALeft - TQtWindowArea(Box).horizontalScrollBar.getValue,
        ATop - TQtWindowArea(Box).verticalScrollBar.getValue, AWidth, AHeight);
    end;
  end;
  {$ENDIF}

  {$IFDEF VerboseQtResize}
  DebugLn('>TQtWSWinControl.SetBounds(',dbgsName(AWinControl),') NewBounds=',dbgs(R));
  {$ENDIF}
  TQtWidget(AWinControl.Handle).BeginUpdate;
  with R do
  begin
    TQtWidget(AWinControl.Handle).move(Left, Top);
    TQtWidget(AWinControl.Handle).resize(Right, Bottom);
  end;
  TQtWidget(AWinControl.Handle).EndUpdate;
  {$IFDEF VerboseQtResize}
  DebugLn('<TQtWSWinControl.SetBounds(',dbgsName(AWinControl),') NewBounds=',dbgs(R));
  {$ENDIF}
end;

{------------------------------------------------------------------------------
  Method: TQtWSWinControl.SetPos
  Params:  AWinControl - the calling object
           ALeft, ATop - Position
  Returns: Nothing

  Sets the position of a widget
 ------------------------------------------------------------------------------}
class procedure TQtWSWinControl.SetPos(const AWinControl: TWinControl;
  const ALeft, ATop: Integer);
begin
  if not WSCheckHandleAllocated(AWincontrol, 'SetPos') then
    Exit;

  TQtWidget(AWinControl.Handle).BeginUpdate;
  TQtWidget(AWinControl.Handle).move(ALeft, ATop);
  TQtWidget(AWinControl.Handle).EndUpdate;
end;

{------------------------------------------------------------------------------
  Method: TQtWSWinControl.SetSize
  Params:  AWinControl     - the calling object
           AWidth, AHeight - Size
  Returns: Nothing

  Sets the size of a widget
 ------------------------------------------------------------------------------}
class procedure TQtWSWinControl.SetSize(const AWinControl: TWinControl;
  const AWidth, AHeight: Integer);
begin
  if not WSCheckHandleAllocated(AWincontrol, 'SetSize') then
    Exit;
  TQtWidget(AWinControl.Handle).BeginUpdate;
  TQtWidget(AWinControl.Handle).resize(AWidth, AHeight);
  TQtWidget(AWinControl.Handle).EndUpdate;
end;

{------------------------------------------------------------------------------
  Method: TQtWSWinControl.ShowHide
  Params:  AWinControl     - the calling object

  Returns: Nothing

  Shows or hides a widget.
 ------------------------------------------------------------------------------}
class procedure TQtWSWinControl.ShowHide(const AWinControl: TWinControl);
var
  Widget: TQtWidget;
begin
  if not WSCheckHandleAllocated(AWincontrol, 'ShowHide') then
    Exit;

  Widget := TQtWidget(AWinControl.Handle);

  Widget.BeginUpdate;
  // issue #28437
  if AWinControl.HandleObjectShouldBeVisible and not AWinControl.IsParentFont and
    (AWinControl.Font.Name = 'default') then
      SetFont(AWinControl, AWinControl.Font);

  Widget.setVisible(AWinControl.HandleObjectShouldBeVisible);
  Widget.EndUpdate;
end;

{------------------------------------------------------------------------------
  Method: TQtWSWinControl.SetColor
  Params:  AWinControl     - the calling object
  Returns: Nothing

  Sets the color of the widget.
 ------------------------------------------------------------------------------}
class procedure TQtWSWinControl.SetColor(const AWinControl: TWinControl);
var
  QColor: TQColor;
  ColorRef: TColorRef;
  QtWidget: TQtWidget;
begin
  if not WSCheckHandleAllocated(AWinControl, 'SetColor') then
    Exit;

  QtWidget := TQtWidget(AWinControl.Handle);
  QtWidget.BeginUpdate;
  QtWidget.WidgetState := QtWidget.WidgetState + [qtwsColorUpdating];
  try
    // Get the color numeric value (system colors are mapped to numeric colors depending on the widget style)
    if AWinControl.Color = clDefault then
      QtWidget.SetDefaultColor(dctBrush)
    else
    begin
      ColorRef := ColorToRGB(AWinControl.Color);

      // Fill QColor
      QColor_fromRgb(@QColor,Red(ColorRef),Green(ColorRef),Blue(ColorRef));

      // Set color of the widget to QColor
      QtWidget.SetColor(@QColor);
    end;
  finally
    QtWidget.WidgetState := QtWidget.WidgetState - [qtwsColorUpdating];
    QtWidget.EndUpdate;
  end;
end;

{------------------------------------------------------------------------------
  Method: TQtWSWinControl.SetCursor
  Params:  AWinControl     - the calling object
  Returns: Nothing

  Sets the cursor of the widget.
 ------------------------------------------------------------------------------}
class procedure TQtWSWinControl.SetCursor(const AWinControl: TWinControl; const ACursor: HCURSOR);
begin
  if not WSCheckHandleAllocated(AWinControl, 'SetCursor') then
    Exit;
  if ACursor <> 0 then
    TQtWidget(AWinControl.Handle).SetCursor(TQtCursor(ACursor).Handle)
  else
    TQtWidget(AWinControl.Handle).SetCursor(nil);
end;

{------------------------------------------------------------------------------
  Method: TQtWSWinControl.SetFont
  Params:  AWinControl - the calling object, AFont - object font
  Returns: Nothing

  Sets the font of the widget.
 ------------------------------------------------------------------------------}
class procedure TQtWSWinControl.SetFont(const AWinControl: TWinControl; const AFont: TFont);
var
  QtWidget: TQtWidget;
  QColor: TQColor;
  ColorRef: TColorRef;
begin
  if not WSCheckHandleAllocated(AWinControl, 'SetFont') then
    Exit;

  QtWidget := TQtWidget(AWinControl.Handle);
  QtWidget.BeginUpdate;
  QtWidget.WidgetState := QtWidget.WidgetState + [qtwsFontUpdating];
  try
    QtWidget.SetLCLFont(TQtFont(AFont.Reference.Handle));
    QtWidget.setFont(TQtFont(AFont.Reference.Handle).FHandle);

    // tscrollbar, ttrackbar etc.
    if not QtWidget.CanChangeFontColor then
    begin
      with QtWidget do
      begin
        Palette.ForceColor := True;
        setDefaultColor(dctFont);
        Palette.ForceColor := False;
      end;
      exit;
    end;

    if AFont.Color = clDefault then
      QtWidget.SetDefaultColor(dctFont)
    else
    begin
      ColorRef := ColorToRGB(AFont.Color);
      QColor_fromRgb(@QColor,Red(ColorRef),Green(ColorRef),Blue(ColorRef));
      QtWidget.SetTextColor(@QColor);
    end;
  finally
    QtWidget.WidgetState := QtWidget.WidgetState - [qtwsFontUpdating];
    QtWidget.EndUpdate;
  end;
end;

class procedure TQtWSWinControl.SetShape(const AWinControl: TWinControl;
  const AShape: HBITMAP);
var
  Widget: TQtWidget;
  Shape: TQtImage;
  AMask: QBitmapH;
begin
  if not WSCheckHandleAllocated(AWinControl, 'SetShape') then
    Exit;
  Widget := TQtWidget(AWinControl.Handle);

  if AShape <> 0 then
  begin
    Shape := TQtImage(AShape);
    // invert white/black
    Shape.invertPixels;
    AMask := Shape.AsBitmap;
    Widget.setMask(AMask);
    QBitmap_destroy(AMask);
    // invert back
    Shape.invertPixels;
  end
  else
    Widget.clearMask;
end;

class procedure TQtWSWinControl.SetBorderStyle(const AWinControl: TWinControl;
  const ABorderStyle: TBorderStyle);
var
  Widget: TQtWidget;
  QtEdit: IQtEdit;
begin
  if not WSCheckHandleAllocated(AWinControl, 'SetBorderStyle') then
    Exit;
    
  Widget := TQtWidget(AWinControl.Handle);
  QtEdit := nil;
  if Widget is TQtFrame then
    TQtFrame(Widget).setFrameShape(TBorderStyleToQtFrameShapeMap[ABorderStyle])
  else
  if Supports(Widget, IQtEdit, QtEdit) then
    QtEdit.setBorder(ABorderStyle = bsSingle);
end;

{ TQtWSDragImageList }

class function TQtWSDragImageList.BeginDrag(
  const ADragImageList: TDragImageList; Window: HWND; AIndex, X, Y: Integer): Boolean;
var
  ABitmap: TBitmap;
begin
  ABitmap := TBitmap.Create;
  ADragImageList.GetBitmap(AIndex, ABitmap);

  if (ABitmap.Handle = 0) or (ABitmap.Width = 0) or (ABitmap.Height = 0) then
  begin
    Result := False;
    Exit;
  end;

  Result := TQtWidgetset(Widgetset).DragImageList_BeginDrag(
    TQtImage(ABitmap.Handle).Handle, ADragImageList.DragHotSpot);
  if Result then
    TQtWidgetset(Widgetset).DragImageList_DragMove(X, Y);
  ABitmap.Free;
end;

class function TQtWSDragImageList.DragMove(
  const ADragImageList: TDragImageList; X, Y: Integer): Boolean;
begin
  Result := TQtWidgetset(Widgetset).DragImageList_DragMove(X, Y);
end;

class procedure TQtWSDragImageList.EndDrag(const ADragImageList: TDragImageList);
begin
  TQtWidgetset(Widgetset).DragImageList_EndDrag;
end;

class function TQtWSDragImageList.HideDragImage(
  const ADragImageList: TDragImageList; ALockedWindow: HWND; DoUnLock: Boolean
  ): Boolean;
begin
  Result := True;
  if DoUnlock then
  begin
    TQtWidgetset(Widgetset).DragImageLock := False;
    Result := TQtWidgetset(Widgetset).DragImageList_SetVisible(False);
  end;
end;

class function TQtWSDragImageList.ShowDragImage(
  const ADragImageList: TDragImageList; ALockedWindow: HWND; X, Y: Integer;
  DoLock: Boolean): Boolean;
begin
  Result := TQtWidgetset(Widgetset).DragImageLock;
  if not DoLock then
  begin
    if not Result then
      Result := TQtWidgetset(Widgetset).DragImageList_SetVisible(True);
  end else
  begin
    TQtWidgetset(Widgetset).DragImageLock := True;
    Result := TQtWidgetset(Widgetset).DragImageList_DragMove(X, Y) and
      TQtWidgetset(Widgetset).DragImageList_SetVisible(True);
  end;
end;

end.
