Delphi多彩的菜单

实例说明

网上的许多应用程序都具有漂亮的菜单。默认情况下，使用Delphi提供的TMainMenu组件只能设置标准的Windows风格菜单，如何能够自定义菜单呢？本实例演示如何自定义菜单，效果如图1.5所示。



1.5Delphi多彩的菜单

技术要点

在Delphi中重新绘制TMainMenu组件，首先需要将OwnerDraw属性设置为True，然后双击TMainMenu组件打开菜单编辑器，添加菜单项。选中菜单项，在对象观察器中编写OnAdvancedDrawItem事件处理过程，OnAdvancedDrawItem事件在菜单项（OwnerDraw属性设置为True）需要绘制时触发。

实现过程

1.新建一个工程，将主窗口命名为Form1。

2.在Form1窗体上放置TImage、TmainMenu和TStatusBar等组件。设置TImage组件的Picture属性，为其加载一幅图像。双击TMainMenu组件，打开菜单编辑窗口，想TMainMenu组件中添加菜单项。

3.程序代码如下：

procedure TForm1.N3AdvancedDrawItem(Sender: TObject; ACanvas: TCanvas;

ARect: TRect; State: TOwnerDrawState);

begin

ACanvas.Brush.Color := clwhite;

if odSelected in State then

begin

ACanvas.Font.Color := clRed;

ACanvas.Pen.Color := clBlue;

ACanvas.Rectangle(Rect(1,(TMenuItem(Sender).Tag-1)*20,ARect.Right-1,(TMenuItem(Sender).Tag-1)*20+15));

NotifyMessage(TMenuItem(Sender).Caption);

end

else

begin

ACanvas.Font.Color := clBlack;

ACanvas.Pen.Color := clWhite;

ACanvas.Rectangle(Rect(1,(TMenuItem(Sender).Tag-1)*20,ARect.Right-1,(TMenuItem(Sender).Tag-1)*20+15));

end;

ACanvas.TextOut(4,(TMenuItem(Sender).Tag-1)*20+2,TMenuItem(Sender).Caption);

end;

procedure TForm1.N1AdvancedDrawItem(Sender: TObject; ACanvas: TCanvas;

ARect: TRect; State: TOwnerDrawState);

begin

SetBkMode(ACanvas.Handle,TRANSPARENT);

if odSelected in State then

begin

ACanvas.Font.Color := clRed;

ACanvas.Pen.Color := clBlue;

ACanvas.Brush.Color := Color;

ACanvas.Rectangle(Rect(TMenuItem(Sender).Tag-2,32,ARect.Right-5,47));

end

else

begin

ACanvas.Font.Color := clBlack;

ACanvas.Pen.Color := Color;

ACanvas.Brush.Color := Color;

ACanvas.Rectangle(Rect(TMenuItem(Sender).Tag-2,32,ARect.Right-5,47));

end;

ACanvas.TextOut(TMenuItem(Sender).Tag,34,TMenuItem(Sender).Caption);

end;