关于tspeedbutton的问题?(20分)

我在Tspeedbutton的ondbclick事件里面输出showmessage('双击事件');
居然没有输出任何东西,,请问这是怎么回事?
我把上面的代码放到onclick事件里面却能正常输出

看看它的源码就知道了，只有在Down=True时才会发生OnDblClick事件
procedure TSpeedButton.WMLButtonDblClk(var Message: TWMLButtonDown);
begin
inherited;
if FDown then DblClick;
end;

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, Buttons;

type
TForm1 = class(TForm)
SpeedButton1: TSpeedButton;
procedure SpeedButton1DblClick(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.SpeedButton1DblClick(Sender: TObject);
begin
showmessage('naniade!');
end;

end.
源码就是这样,没有做任何改动,就在窗口上放了个tspeedbutton,,但是我去设置它的down属性的时候不能设置成true

你要把他的GroupIndex属性设置成非0才能设置他的Down属性为True...

接受答案了.