一个简单的菜单按钮的实现

      使用过速达2000的朋友都知道,其基本资料的浏览界面中有一种按钮,点击后会弹出一个和按钮对得很整齐的菜单.用Delphi制作一个类似的控件十分容易,代码如下:

unit MenuBtnVCL;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  Buttons, CommCtrl,
  ExtCtrls,Menus;

type
  TMenuBtn = class(TBitBtn)
  protected
    procedure DoEnter;override;
    procedure DoExit;override;
    { Protected declarations }
  public
    constructor Create(AOwner: TComponent); override;
    procedure Click; override;
    { Public declarations }
  published
    { AL: }
    { Published declarations }
  end;

procedure Register;

implementation

procedure Register;
begin
  RegisterComponents('Samples', [TMenuBtn]);
end;

constructor TMenuBtn.Create(AOwner: TComponent);
begin
   inherited Create(AOwner);
   layout:=blGlyphRight;
   Font.Charset := GB2312_CHARSET;
   Font.Color := clWindowText;
   Font.Height := -12;
   Font.Name := '宋体';
end;

procedure TMenuBtn.Click;
var tmp:TPoint;
begin
  inherited Click;

   if Assigned(PopUpMenu) then
   begin
     { calc where to put menu }
     tmp := ClientToScreen(Point(0, Height));
     PopUpMenu.Popup(tmp.X, tmp.Y);
   end;
end;

procedure TMenuBtn.DoEnter;
begin
   Font.Style := [fsBold];
   inherited DoEnter;
end;

procedure TMenuBtn.DoExit ;
begin
   Font.Style := [];
   inherited DoExit;
end;

end.

本文地址：http://com.8s8s.com/it/it5725.htm