: Boolean);



    procedure SetRightMargin(const Value: Cardinal);



    function GetBoundsRect: TRect;



    procedure NewWndProc(var message: TMessage);



  protected



    procedure Notification(Component: TComponent;Operation: TOperation); override;



    procedure Paint; virtual;



  public



    constructor Create(AOwner: TComponent); override;



    destructor Destroy; override;



    procedure Repaint;



    property BoundsRect: TRect read GetBoundsRect;



  published



    property Color: TColor read FColor write FColor default clBtnFace;



    property Glyph: TBitmap read FGlyph write SetGlyph;



    property PopupMenu: TPopupMenu read FPopup write FPopup;



    property RightMargin: Cardinal read FRightMargin write SetRightMargin default 66;



    property Visible: Boolean read FVisible write SetVisible default False;



    property OnClick: TNotifyEvent read FOnClick write FOnClick;



  end;







procedure Register;







implementation







procedure Register;



begin



  RegisterComponents(''Liao'', [TTitleBarButton]);



end;







{ TTitleBarButton }







constructor TTitleBarButton.Create(AOwner: TComponent);



var



  ptr: Pointer;



begin



  inherited;



  FForm := GetParentForm(TControl(AOwner));



  FGlyph := TBitmap.Create;



  FColor := clBtnFace;



  FVisible := False;



  FRightMargin := 66;



  FButtonDown := False;



  FOldWndProc := Pointer(GetWindowLong(FForm.Handle,GWL_WNDPROC));



  ptr := MakeObjectInstance(NewWndProc);



  SetWindowLong(FForm.Handle, GWL_WNDPROC, Longint(ptr));



end;







destructor TTitleBarButton.Destroy;



begin



  if not (csDestroying in FForm.ComponentState) then



  begin



    SetVisible(false);



    SetWindowLong(FForm.Handle, GWL_WNDPROC, LongInt(FOldWndProc));



  end;



  FGlyph.Free;



  inherited;



end;







procedure TTitleBarButton.NewWndProc(var message: TMessage);







  function HitButton(APoint: TPoint): Boolean;



  begin



    APoint.x := APoint.x - FForm.Left;



    APoint.y := APoint.y - FForm.Top;



    Result := PtInRect(BoundsRect,APoint);



  end;







var



  p: TPoint;



begin



  with message do



  begin



    if Visible then



    begin



      case Msg of



        WM_NCPAINT , WM_NCACTIVATE :



          begin



            Result := CallWindowProc(FOldWndProc,FForm.Handle,Msg,WParam,LParam);