anchor.diff:    ApplyButtonLayout;
   end;
   
  +procedure TATTabs.SetOptMouseDragEnabled(AValue: boolean);
  +begin
  +  if FOptMouseDragEnabled=AValue then Exit;
  +
  +  {$ifdef FPC}
  +  FOptMouseDragEnabled:= AValue;
  +  {$else}
  +  ShowMessage('Dragging of tabs is not yet implemented under Delphi, sorry');
  +  FOptMouseDragEnabled:= false;
  +  {$endif}
  +end;
  +
   procedure TATTabs.SetOptVarWidth(AValue: boolean);
   begin
     if FOptVarWidth=AValue then Exit;
  
positive.code:   D: TATTabData;
    R: TRect;
  begin
    if not IsScrollMarkNeeded then exit(true);
  
    D:= GetTabData(AIndex);
    if D=nil then exit(false);
    R:= D.TabRect;
  
    case FOptPosition of
  
negative.code:     property OptMouseMiddleClickClose: boolean read FOptMouseMiddleClickClose write FOptMouseMiddleClickClose default _InitOptMouseMiddleClickClose;
      property OptMouseDoubleClickClose: boolean read FOptMouseDoubleClickClose write FOptMouseDoubleClickClose default _InitOptMouseDoubleClickClose;
      property OptMouseDoubleClickPlus: boolean read FOptMouseDoubleClickPlus write FOptMouseDoubleClickPlus default _InitOptMouseDoubleClickPlus;
      property OptMouseDragEnabled: boolean read FOptMouseDragEnabled write SetOptMouseDragEnabled default _InitOptMouseDragEnabled;
      property OptMouseDragOutEnabled: boolean read FOptMouseDragOutEnabled write FOptMouseDragOutEnabled default _InitOptMouseDragOutEnabled;
  
      //events
  