[JVCL-Checkins] dev/JVCL3/run JvTabBar.pas,1.27,1.28 - ScrollButtons are now painted by the TabBarPainter

[Andreas H. <ah...@us...>]

Update of /cvsroot/jvcl/dev/JVCL3/run
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv17375/run

Modified Files:
	JvTabBar.pas 
Log Message:
ScrollButtons are now painted by the TabBarPainter


Index: JvTabBar.pas
===================================================================
RCS file: /cvsroot/jvcl/dev/JVCL3/run/JvTabBar.pas,v
retrieving revision 1.27
retrieving revision 1.28
diff -C2 -d -r1.27 -r1.28
*** JvTabBar.pas	5 May 2005 20:11:32 -0000	1.27
--- JvTabBar.pas	11 May 2005 23:20:45 -0000	1.28
***************
*** 60,63 ****
--- 60,65 ----
  
    TJvTabBarOrientation = (toTop, toBottom);
+   TJvTabBarScrollButtonKind = (sbScrollLeft, sbScrollRight);
+   TJvTabBarScrollButtonState = (sbsHidden, sbsNormal, sbsHot, sbsPressed, sbsDisabled);
  
    TJvGetModifiedEvent = procedure(Sender: TJvTabBarItem; var Modified: Boolean) of object;
***************
*** 170,174 ****
    end;
  
!   TJvTabBarPainterOptionType = (poPaintsHotTab);
    TJvTabBarPainterOptions = set of TJvTabBarPainterOptionType;
  
--- 172,176 ----
    end;
  
!   TJvTabBarPainterOptionType = (poPaintsHotTab, poBottomScrollButtons);
    TJvTabBarPainterOptions = set of TJvTabBarPainterOptionType;
  
***************
*** 187,190 ****
--- 189,196 ----
      function GetCloseRect(Canvas: TCanvas; Tab: TJvTabBarItem; R: TRect): TRect; virtual; abstract;
      function Options: TJvTabBarPainterOptions; virtual; abstract;
+ 
+     procedure DrawScrollButton(Canvas: TCanvas; TabBar: TJvCustomTabBar; Button: TJvTabBarScrollButtonKind;
+       State: TJvTabBarScrollButtonState; R: TRect); virtual;
+     procedure GetScrollButtons(TabBar: TJvCustomTabBar; var LeftButton, RightButton: TRect); {virtual; reserved for future use }
    end;
  
***************
*** 267,270 ****
--- 273,277 ----
    TJvTabBarSelectingEvent = procedure(Sender: TObject; Item: TJvTabBarItem; var AllowSelect: Boolean) of object;
    TJvTabBarClosingEvent = procedure(Sender: TObject; Item: TJvTabBarItem; var AllowClose: Boolean) of object;
+   TJvTabBarScrollButtonClickEvent = procedure(Sender: TObject; Button: TJvTabBarScrollButtonKind) of object;
  
    TJvCustomTabBar = class(TCustomControl)
***************
*** 300,311 ****
      FRequiredWidth: Integer;
      FBarWidth: Integer;
!     FBtnLeftScroll: TSpeedButton;
!     FBtnRightScroll: TSpeedButton;
!     FBmpLeftScroll: TBitmap;
!     FBmpRightScroll: TBitmap;
      FHint: TCaption;
      FFlatScrollButtons: Boolean;
      FAllowTabMoving: Boolean;
      FOrientation: TJvTabBarOrientation;
  
      function GetLeftTab: TJvTabBarItem;
--- 307,322 ----
      FRequiredWidth: Integer;
      FBarWidth: Integer;
!     FBtnLeftScroll: TJvTabBarScrollButtonState;
!     FBtnRightScroll: TJvTabBarScrollButtonState;
!     FBtnLeftScrollRect: TRect;
!     FBtnRightScrollRect: TRect;
!     FBtnLeftScrollExState: Boolean;
!     FBtnRightScrollExState: Boolean;
!     FScrollButtonBackground: TBitmap;
      FHint: TCaption;
      FFlatScrollButtons: Boolean;
      FAllowTabMoving: Boolean;
      FOrientation: TJvTabBarOrientation;
+     FOnScrollButtonClick: TJvTabBarScrollButtonClickEvent;
  
      function GetLeftTab: TJvTabBarItem;
***************
*** 321,325 ****
      procedure SetClosingTab(Tab: TJvTabBarItem);
      procedure UpdateScrollButtons;
-     function GetScrollBarGlyph(Left: Boolean): TBitmap;
      function FindSelectableTab(Tab: TJvTabBarItem): TJvTabBarItem;
      procedure SetHint(const Value: TCaption);
--- 332,335 ----
***************
*** 328,335 ****
--- 338,347 ----
      procedure SetOrientation(const Value: TJvTabBarOrientation);
    protected
+     procedure DrawScrollBarGlyph(Canvas: TCanvas; X, Y: Integer; Left, Disabled: Boolean);
      procedure Resize; override;
      procedure CalcTabsRects;
      procedure Paint; override;
      procedure PaintTab(Canvas: TCanvas; Tab: TJvTabBarItem); virtual;
+     procedure PaintScrollButtons;
  
      function GetTabWidth(Tab: TJvTabBarItem): Integer;
***************
*** 345,349 ****
      procedure Changed; virtual;
      procedure ImagesChanged(Sender: TObject); virtual;
!     procedure ScrollButtonClicked(Sender: TObject); virtual;
  
      procedure DragOver(Source: TObject; X: Integer; Y: Integer;
--- 357,361 ----
      procedure Changed; virtual;
      procedure ImagesChanged(Sender: TObject); virtual;
!     procedure ScrollButtonClick(Button: TJvTabBarScrollButtonKind); virtual;
  
      procedure DragOver(Source: TObject; X: Integer; Y: Integer;
***************
*** 351,354 ****
--- 363,370 ----
      procedure DragCanceled; override;
  
+     function ScrollButtonsMouseDown(Button: TMouseButton; Shift: TShiftState; X: Integer; Y: Integer): Boolean; virtual;
+     function ScrollButtonsMouseUp(Button: TMouseButton; Shift: TShiftState; X: Integer; Y: Integer): Boolean; virtual;
+     function ScrollButtonsMouseMove(Shift: TShiftState; X: Integer; Y: Integer): Boolean; virtual;
+ 
      procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X: Integer; Y: Integer); override;
      procedure MouseUp(Button: TMouseButton; Shift: TShiftState; X: Integer; Y: Integer); override;
***************
*** 359,362 ****
--- 375,379 ----
      {$ENDIF VCL}
      {$IFDEF VisualCLX}
+     procedure InitWidget; override;
      procedure MouseLeave(AControl: TControl); override;
      {$ENDIF VisualCLX}
***************
*** 403,406 ****
--- 420,424 ----
      property OnTabSelected: TJvTabBarItemEvent read FOnTabSelected write FOnTabSelected;
      property OnChange: TNotifyEvent read FOnChange write FOnChange;
+     property OnScrollButtonClick: TJvTabBarScrollButtonClickEvent read FOnScrollButtonClick write FOnScrollButtonClick;
    end;
  
***************
*** 514,518 ****
  begin
    inherited Create(AOwner);
!   ControlStyle := ControlStyle - [csAcceptsControls];
    
    FTabs := TJvTabBarItems.Create(Self, TJvTabBarItem);
--- 532,536 ----
  begin
    inherited Create(AOwner);
!   ControlStyle := ControlStyle - [csAcceptsControls, csOpaque];
    
    FTabs := TJvTabBarItems.Create(Self, TJvTabBarItem);
***************
*** 543,548 ****
    FChangeLink.Free;
    FreeAndNil(FTabs);
!   FreeAndNil(FBmpLeftScroll);
!   FreeAndNil(FBmpRightScroll);
    inherited Destroy;
  end;
--- 561,565 ----
    FChangeLink.Free;
    FreeAndNil(FTabs);
!   FreeAndNil(FScrollButtonBackground);
    inherited Destroy;
  end;
***************
*** 569,612 ****
  end;
  
! function TJvCustomTabBar.GetScrollBarGlyph(Left: Boolean): TBitmap;
  const
!   W = 6;
!   H = 6;
  var
    Pts: array [0..2] of TPoint;
  begin
!   if Left then
!     Result := FBmpLeftScroll
!   else
!     Result := FBmpRightScroll;
! 
!   if not Assigned(Result) then
!   begin
!     Result := TBitmap.Create;
!     Result.Width := 8;
!     Result.Height := 8;
  
      if Left then
      begin
!       Pts[0] := Point(W div 2 + 1, 0);
!       Pts[1] := Point(W div 2 + 1, H);
!       Pts[2] := Point(0 + 1, H div 2);
      end
      else
      begin
!       Pts[0] := Point(W div 2 - 1, 0);
!       Pts[1] := Point(W div 2 - 1, H);
!       Pts[2] := Point(W - 1, H div 2);
      end;
!     Result.Canvas.Brush.Style := bsSolid;
!     Result.Canvas.Brush.Color := clBlack;
!     Result.Canvas.Pen.Color := Result.Canvas.Brush.Color;
!     Result.Canvas.Polygon(Pts)
!   end;
  
!   if Left then
!     FBmpLeftScroll := Result
!   else
!     FBmpRightScroll := Result;
  end;
  
--- 586,648 ----
  end;
  
! procedure TJvCustomTabBar.DrawScrollBarGlyph(Canvas: TCanvas; X, Y: Integer; Left, Disabled: Boolean);
! 
!   procedure OffsetPt(var Pt: TPoint; X, Y: Integer);
!   begin
!     Pt := Point(Pt.X + X, Pt.Y + Y);
!   end;
! 
  const
!   W = 4;
!   H = 7;
  var
    Pts: array [0..2] of TPoint;
+   Brush: TBrush;
+   Pen: TPen;
  begin
!   Brush := TBrush.Create;
!   Pen := TPen.Create;
!   try
!     Brush.Assign(Canvas.Brush);
!     Pen.Assign(Canvas.Pen);
  
      if Left then
      begin
!       Pts[0] := Point(X + W - 1, Y + 0);
!       Pts[1] := Point(X + W - 1, Y + H - 1);
!       Pts[2] := Point(X + 0, Y + (H - 1) div 2);
      end
      else
      begin
!       Pts[0] := Point(X + 0, Y + 0);
!       Pts[1] := Point(X + 0, Y + H - 1);
!       Pts[2] := Point(X + W - 1, Y + (H - 1) div 2);
      end;
!     Canvas.Brush.Style := bsSolid;
!     if Disabled then
!     begin
!       Canvas.Brush.Color := clWhite;
!       OffsetPt(Pts[0], 1, 1);
!       OffsetPt(Pts[1], 1, 1);
!       OffsetPt(Pts[2], 1, 1);
!     end
!     else
!       Canvas.Brush.Color := clBlack;
  
!     Canvas.Pen.Color := Canvas.Brush.Color;
!     Canvas.Polygon(Pts);
!     if Disabled then
!     begin
!       Canvas.Brush.Color := clGray;
!       OffsetPt(Pts[0], -1, -1);
!       OffsetPt(Pts[1], -1, -1);
!       OffsetPt(Pts[2], -1, -1);
!       Canvas.Pen.Color := Canvas.Brush.Color;
!       Canvas.Polygon(Pts);
!     end;
!   finally
!     Canvas.Pen.Assign(Pen);
!     Canvas.Brush.Assign(Brush);
!   end;
  end;
  
***************
*** 889,892 ****
--- 925,934 ----
  
  {$IFDEF VisualCLX}
+ procedure TJvCustomTabBar.InitWidget;
+ begin
+   inherited InitWidget;
+   QWidget_setBackgroundMode(Handle, QWidgetBackgroundMode_NoBackground); // reduces flicker
+ end;
+ 
  procedure TJvCustomTabBar.MouseLeave(AControl: TControl);
  begin
***************
*** 902,905 ****
--- 944,950 ----
    LastSelected: TJvTabBarItem;
  begin
+   if ScrollButtonsMouseDown(Button, Shift, X, Y) then
+     Exit;
+ 
    if Button = mbLeft then
    begin
***************
*** 933,936 ****
--- 978,984 ----
    Tab: TJvTabBarItem;
  begin
+   if ScrollButtonsMouseUp(Button, Shift, X, Y) then
+     Exit;
+ 
    try
      if RightClickSelect and not Assigned(PopupMenu) and (Button = mbRight) then
***************
*** 968,972 ****
    NewHint: TCaption;
  begin
!   CalcTabsRects;
    Tab := TabAt(X, Y);
    if HotTracking and ([ssLeft, ssMiddle, ssRight] * Shift = []) then
--- 1016,1023 ----
    NewHint: TCaption;
  begin
!   CalcTabsRects; // maybe inefficent
!   if ScrollButtonsMouseMove(Shift, X, Y) then
!     Exit;
! 
    Tab := TabAt(X, Y);
    if HotTracking and ([ssLeft, ssMiddle, ssRight] * Shift = []) then
***************
*** 998,1001 ****
--- 1049,1158 ----
  end;
  
+ function TJvCustomTabBar.ScrollButtonsMouseDown(Button: TMouseButton;
+   Shift: TShiftState; X, Y: Integer): Boolean;
+ 
+   function HandleButton(Kind: TJvTabBarScrollButtonKind; var State: TJvTabBarScrollButtonState;
+     X, Y: Integer; const R: TRect): Boolean;
+   begin
+     Result := PtInRect(R, Point(X, Y));
+     case State of
+       sbsNormal, sbsHot:
+         begin
+           if Result then
+           begin
+             State := sbsPressed;
+             PaintScrollButtons;
+           end;
+         end;
+     end;
+   end;
+ 
+ begin
+   Result := False;
+   if (FBtnLeftScroll <> sbsHidden) then
+     Result := HandleButton(sbScrollLeft, FBtnLeftScroll, X, Y, FBtnLeftScrollRect);
+   if (FBtnRightScroll <> sbsHidden) then
+     Result := HandleButton(sbScrollRight, FBtnRightScroll, X, Y, FBtnRightScrollRect);
+ end;
+ 
+ function TJvCustomTabBar.ScrollButtonsMouseMove(Shift: TShiftState; X, Y: Integer): Boolean;
+ 
+   function HandleButton(var ExState: Boolean; var State: TJvTabBarScrollButtonState;
+     X, Y: Integer; const R: TRect): Boolean;
+   begin
+     Result := PtInRect(R, Point(X, Y));
+     case State of
+       sbsNormal:
+         begin
+           if Result then
+           begin
+             State := sbsHot;
+             PaintScrollButtons;
+             Result := True;
+           end;
+         end;
+       sbsPressed:
+         begin
+           if not Result then
+           begin
+             ExState := True;
+             State := sbsNormal;
+             PaintScrollButtons;
+             State := sbsPressed;
+           end
+           else
+           begin
+             if ExState then
+             begin
+               ExState := False;
+               PaintScrollButtons;
+             end;
+           end;
+         end;
+       sbsHot:
+         begin
+           if not Result then
+           begin
+             State := sbsNormal;
+             PaintScrollButtons;
+           end;
+         end;
+     end;
+   end;
+ 
+ begin
+   Result := False;
+   if (FBtnLeftScroll <> sbsHidden) then
+     Result := HandleButton(FBtnLeftScrollExState, FBtnLeftScroll, X, Y, FBtnLeftScrollRect);
+   if (FBtnRightScroll <> sbsHidden) then
+     Result := HandleButton(FBtnRightScrollExState, FBtnRightScroll, X, Y, FBtnRightScrollRect);
+ end;
+ 
+ function TJvCustomTabBar.ScrollButtonsMouseUp(Button: TMouseButton;
+   Shift: TShiftState; X, Y: Integer): Boolean;
+ 
+   function HandleButton(Kind: TJvTabBarScrollButtonKind; var State: TJvTabBarScrollButtonState;
+     X, Y: Integer; const R: TRect): Boolean;
+   begin
+     Result := PtInRect(R, Point(X, Y));
+     case State of
+       sbsPressed:
+         begin
+           State := sbsNormal;
+           PaintScrollButtons;
+           if Result then
+             ScrollButtonClick(Kind);
+         end;
+     end;
+   end;
+ 
+ begin
+   Result := False;
+   if (FBtnLeftScroll <> sbsHidden) then
+     Result := HandleButton(sbScrollLeft, FBtnLeftScroll, X, Y, FBtnLeftScrollRect);
+   if (FBtnRightScroll <> sbsHidden) then
+     Result := HandleButton(sbScrollRight, FBtnRightScroll, X, Y, FBtnRightScrollRect);
+ end;
+ 
  procedure TJvCustomTabBar.SetHotTab(Tab: TJvTabBarItem);
  begin
***************
*** 1066,1072 ****
  end;
  
- type
-   TSpeedButtonAccess = class(TSpeedButton);
-   
  procedure TJvCustomTabBar.Paint;
  var
--- 1223,1226 ----
***************
*** 1081,1091 ****
      Bmp.Height := ClientHeight;
      CurrentPainter.DrawBackground(Bmp.Canvas, Self, ClientRect);
!     if Assigned(FBtnLeftScroll) and Assigned(FBtnRightScroll) then
      begin
!       // paint scroll button's background and the buttons
        R := Rect(FBarWidth, 0, Bmp.Width, Bmp.Height);
!       Canvas.CopyRect(R, Bmp.Canvas, R);
!       TSpeedButtonAccess(FBtnLeftScroll).Paint;
!       TSpeedButtonAccess(FBtnRightScroll).Paint;
        if FBarWidth > 0 then
          Bmp.Width := FBarWidth;
--- 1235,1247 ----
      Bmp.Height := ClientHeight;
      CurrentPainter.DrawBackground(Bmp.Canvas, Self, ClientRect);
!     if (FBtnLeftScroll <> sbsHidden) and (FBtnRightScroll <> sbsHidden) then
      begin
!       if not Assigned(FScrollButtonBackground) then
!         FScrollButtonBackground := TBitmap.Create;
!       FScrollButtonBackground.Width := Bmp.Width - FBarWidth;
!       FScrollButtonBackground.Height := Bmp.Height;
        R := Rect(FBarWidth, 0, Bmp.Width, Bmp.Height);
!       FScrollButtonBackground.Canvas.CopyRect(Rect(0, 0, FScrollButtonBackground.Width, R.Bottom), Bmp.Canvas, R);
!       PaintScrollButtons;
        if FBarWidth > 0 then
          Bmp.Width := FBarWidth;
***************
*** 1122,1125 ****
--- 1278,1292 ----
  end;
  
+ procedure TJvCustomTabBar.PaintScrollButtons;
+ begin
+   if not Assigned(FScrollButtonBackground) and Visible then
+     Paint
+   else
+     // paint scroll button's background and the buttons
+     Canvas.Draw(FBarWidth, 0, FScrollButtonBackground);
+   CurrentPainter.DrawScrollButton(Canvas, Self, sbScrollLeft, FBtnLeftScroll, FBtnLeftScrollRect);
+   CurrentPainter.DrawScrollButton(Canvas, Self, sbScrollRight, FBtnRightScroll, FBtnRightScrollRect);
+ end;
+ 
  function TJvCustomTabBar.GetTabHeight(Tab: TJvTabBarItem): Integer;
  begin
***************
*** 1137,1141 ****
    Pt: TPoint;
  begin
!   if not Assigned(FBtnLeftScroll) or (X < FBarWidth) then
    begin
      CalcTabsRects;
--- 1304,1308 ----
    Pt: TPoint;
  begin
!   if (FBtnLeftScroll = sbsHidden) or (X < FBarWidth) then
    begin
      CalcTabsRects;
***************
*** 1212,1215 ****
--- 1379,1383 ----
  procedure TJvCustomTabBar.UpdateScrollButtons;
  const
+   State: array[Boolean] of TJvTabBarScrollButtonState = (sbsDisabled, sbsNormal);
    BtnSize = 12;
  begin
***************
*** 1218,1223 ****
      (FLastTabRight <= ClientWidth)) then
    begin
!     FreeAndNil(FBtnLeftScroll);
!     FreeAndNil(FBtnRightScroll);
      FLeftIndex := 0;
      FBarWidth := ClientWidth;
--- 1386,1391 ----
      (FLastTabRight <= ClientWidth)) then
    begin
!     FBtnLeftScroll := sbsHidden;
!     FBtnRightScroll := sbsHidden;
      FLeftIndex := 0;
      FBarWidth := ClientWidth;
***************
*** 1226,1257 ****
    else
    begin
!     if not Assigned(FBtnLeftScroll) then
      begin
!       FBtnLeftScroll := TSpeedButton.Create(Self);
!       FBtnLeftScroll.Caption := '';
!       FBtnLeftScroll.Flat := FlatScrollButtons;
!       FBtnLeftScroll.Parent := Self;
!       FBtnLeftScroll.OnClick := ScrollButtonClicked;
!       FBtnLeftScroll.Glyph := GetScrollBarGlyph(True);
!     end;
!     if not Assigned(FBtnRightScroll) then
      begin
!       FBtnRightScroll := TSpeedButton.Create(Self);
!       FBtnRightScroll.Caption := '';
!       FBtnRightScroll.Flat := FlatScrollButtons;
!       FBtnRightScroll.Parent := Self;
!       FBtnRightScroll.OnClick := ScrollButtonClicked;
!       FBtnRightScroll.Glyph := GetScrollBarGlyph(False);
      end;
  
!     FBtnLeftScroll.SetBounds(ClientWidth - BtnSize * 2 - 1 - 1,
!       ClientHeight - BtnSize - 2, BtnSize, BtnSize);
!     FBtnRightScroll.SetBounds(ClientWidth - BtnSize - 1 - 1,
!       ClientHeight - BtnSize - 2, BtnSize, BtnSize);
  
!     FBarWidth := FBtnLeftScroll.Left - 2;
  
!     FBtnLeftScroll.Enabled := FLeftIndex > 0;
!     FBtnRightScroll.Enabled := FLastTabRight > ClientWidth;
    end;
  end;
--- 1394,1423 ----
    else
    begin
!     FBtnLeftScroll := sbsNormal;
!     FBtnRightScroll := sbsNormal;
! 
!     if poBottomScrollButtons in CurrentPainter.Options then
      begin
!       FBtnLeftScrollRect := Bounds(ClientWidth - BtnSize * 2 - 1 - 1,
!         ClientHeight - BtnSize - 2, BtnSize, BtnSize);
!       FBtnRightScrollRect := Bounds(FBtnLeftScrollRect.Right,
!         ClientHeight - BtnSize - 2, BtnSize, BtnSize);
!     end
!     else
      begin
!       FBtnLeftScrollRect := Bounds(ClientWidth - BtnSize * 2 - 1 - 1, 2, BtnSize, BtnSize);
!       FBtnRightScrollRect := Bounds(FBtnLeftScrollRect.Right, 2, BtnSize, BtnSize);
      end;
+     if not FlatScrollButtons then
+       OffsetRect(FBtnRightScrollRect, -1, 0);
  
!     //CurrentPainter.GetScrollButtons(Self, FBtnLeftScrollRect, FBtnRightScrollRect);
  
!     FBarWidth := FBtnLeftScrollRect.Left - 2;
  
!     FBtnLeftScroll := State[FLeftIndex > 0];
!     FBtnRightScroll := State[FLastTabRight >= ClientWidth];
! 
!     PaintScrollButtons;
    end;
  end;
***************
*** 1263,1275 ****
  end;
  
! procedure TJvCustomTabBar.ScrollButtonClicked(Sender: TObject);
  begin
!   if Sender = FBtnLeftScroll then
      Dec(FLeftIndex)
    else
!   if Sender = FBtnRightScroll then
      Inc(FLeftIndex);
    UpdateScrollButtons;
    Invalidate;
  end;
  
--- 1429,1443 ----
  end;
  
! procedure TJvCustomTabBar.ScrollButtonClick(Button: TJvTabBarScrollButtonKind);
  begin
!   if Button = sbScrollLeft then
      Dec(FLeftIndex)
    else
!   if Button = sbScrollRight then
      Inc(FLeftIndex);
    UpdateScrollButtons;
    Invalidate;
+   if Assigned(FOnScrollButtonClick) then
+     FOnScrollButtonClick(Self, Button);
  end;
  
***************
*** 1330,1335 ****
    begin
      FFlatScrollButtons := Value;
!     FreeAndNil(FBtnLeftScroll);
!     FreeAndNil(FBtnRightScroll);
      UpdateScrollButtons;
    end;
--- 1498,1503 ----
    begin
      FFlatScrollButtons := Value;
!     FBtnLeftScroll := sbsHidden;
!     FBtnRightScroll := sbsHidden;
      UpdateScrollButtons;
    end;
***************
*** 1667,1670 ****
--- 1835,1863 ----
  end;
  
+ procedure TJvTabBarPainter.GetScrollButtons(TabBar: TJvCustomTabBar; var LeftButton, RightButton: TRect);
+ begin
+   { reserved for future use }
+ end;
+ 
+ procedure TJvTabBarPainter.DrawScrollButton(Canvas: TCanvas; TabBar: TJvCustomTabBar; Button: TJvTabBarScrollButtonKind;
+   State: TJvTabBarScrollButtonState; R: TRect);
+ begin
+   {$IFDEF VCL}
+   if TabBar.FlatScrollButtons then
+     DrawButtonFace(Canvas, R, 1, bsNew, False, State = sbsPressed, False)
+   else
+     DrawButtonFace(Canvas, R, 1, bsWin31, False, State = sbsPressed, False);
+   {$ENDIF VCL}
+   {$IFDEF VisualCLX}
+   DrawButtonFace(Canvas, R, 1, State = sbsPressed, False, TabBar.FlatScrollButtons);
+   {$ENDIF VisualCLX}
+   if State = sbsPressed then
+     OffsetRect(R, 1, 1);
+   TabBar.DrawScrollBarGlyph(Canvas,
+     R.Left + (R.Right - R.Left - 4) div 2,
+     R.Top + (R.Bottom - R.Top - 7) div 2,
+     Button = sbScrollLeft, State = sbsDisabled);
+ end;
+ 
  //=== { TJvModernTabBarPainter } =============================================