一個簡單的選單按鈕的實現 (轉)

一個簡單的選單按鈕的實現 (轉)[@more@]

  使用過速達2000的朋友都知道,其基本資料的瀏覽介面中有一種按鈕,點選後會彈出一個和按鈕對得很整齊的選單.用製作一個類似的十分容易,程式碼如下:

unit MenuBtnVCL;

interface

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

type
  TMenuBtn = class(TBitBtn)
  protected
  procedure DoEnter;overr;
  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 := '宋體';
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.