关于 panel继承 Canvas 后重绘闪烁问题

[wealsh]

我在 Panel 继承了 Canvas ，用一个线程不停地绘图，当鼠标在窗口或其它控件上面随便移动一下 这个 panel 就会闪烁，鼠标在窗口外就没问题，请问为什么？谢谢。

主窗口 与 panel
DoubleBuffered:=True;也没效果

[hsfzxjy]

什么叫继承了canvas?是某控件继承自panel然后重写canvas属性，还是你的panel继承自canvaa?你这样说让人迷惑。。

[BambooCaep]

从tcustomcontrol继承吧。

[wealsh]

TWealshPnl = class(TPanel)
private
FOnMouseEnter: TNotifyEvent;
FOnMouseLeave: TNotifyEvent;
FPaint:TNotifyEvent;
procedure CMMouseEnter(var Message: TMessage); message CM_MOUSEENTER;
procedure CMMouseLeave(var Message: TMessage); message CM_MOUSELEAVE;
protected
procedure Paint;override;
public
TmpSpBmp:TBitmap;
procedure CBShowSp(pData:Pointer;pSize:Integer);
property Canvas;
procedure ResizeBmp1(SrcBM, DstBM: TBitmap; Nwide, Nheight: integer);
published
property OnMouseEnter:TNotifyEvent read FOnMouseEnter write FOnMouseEnter;
property OnMouseLeave:TNotifyEvent read FOnMouseLeave write FOnMouseLeave;
property OnPaint:TNotifyEvent read FPaint write FPaint;
end;




procedure TWealshPnl.CBShowSp(pData:Pointer;pSize:Integer);
var
B:TBitmap;
begin
if not Assigned(TmpSpBmp) then
begin
TmpSpBmp:=TBitmap.Create;
DoubleBuffered:=True;
end;
TmpSpBmp.Canvas.Lock;
Canvas.Lock;
TmpSpBmp.Handle := HBitmap(pData^);
B:=TBitmap.Create;
ResizeBmp1(TmpSpBmp,B,Width-6,Height-6);
Canvas.Draw(3,3,B);
B.Free;
end;

[wealsh]

TWealshPnl = class(TPanel)
private
FOnMouseEnter: TNotifyEvent;
FOnMouseLeave: TNotifyEvent;
FPaint:TNotifyEvent;
procedure CMMouseEnter(var Message: TMessage); message CM_MOUSEENTER;
procedure CMMouseLeave(var Message: TMessage); message CM_MOUSELEAVE;
protected
procedure Paint;override;
public
TmpSpBmp:TBitmap;
procedure CBShowSp(pData:Pointer;pSize:Integer);
property Canvas;
procedure ResizeBmp1(SrcBM, DstBM: TBitmap; Nwide, Nheight: integer);
published
property OnMouseEnter:TNotifyEvent read FOnMouseEnter write FOnMouseEnter;
property OnMouseLeave:TNotifyEvent read FOnMouseLeave write FOnMouseLeave;
property OnPaint:TNotifyEvent read FPaint write FPaint;
end;




procedure TWealshPnl.CBShowSp(pData:Pointer;pSize:Integer);
var
B:TBitmap;
begin
if not Assigned(TmpSpBmp) then
begin
TmpSpBmp:=TBitmap.Create;
DoubleBuffered:=True;
end;
TmpSpBmp.Canvas.Lock;
Canvas.Lock;
TmpSpBmp.Handle := HBitmap(pData^);
B:=TBitmap.Create;
ResizeBmp1(TmpSpBmp,B,Width-6,Height-6);
Canvas.Draw(3,3,B);
B.Free;
end;

[littlestone08]

果然，盒子上的就是你。看盒子上的回复吧。要不你盒子上留QQ

[littlestone08]

看盒子吧，要不你在盒子上留Q

[Pinck]

使用双缓存，每次重绘时用缓存里的图形，而不是直接在Draw里绘制