这是来宾 Dolby 在 http://www.cnblogs.com/del/archive/2008/03/08/1081295.html#1096814 询问的问题.
//声明:
SetLayeredWindowAttributes(
  Hwnd: THandle;   {窗口句柄}
  crKey: COLORREF; {透明色}
  bAlpha: Byte;    {Alpha 值}
  dwFlags: DWORD   {LWA_COLORKEY(=1)表示使用透明色; LWA_ALPHA(=2)表示使用 Alpha 值}
): Boolean;        {是否成功设置}

//举例(控制外部程序的透明度, 用计算器举了个例子): unit Unit1; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls; type TForm1 = class(TForm) Button1: TButton; Button2: TButton; procedure Button1Click(Sender: TObject); procedure Button2Click(Sender: TObject); end; var Form1: TForm1; implementation {$R *.dfm} {设定计算器的 Alpha 透明} procedure TForm1.Button1Click(Sender: TObject); var h: HWND; FormStyle: Integer; begin h := FindWindow('SciCalc', nil); FormStyle := GetWindowLong(h, GWL_EXSTYLE); SetWindowLong(h, GWL_EXSTYLE, FormStyle or WS_EX_LAYERED); SetLayeredWindowAttributes(h, 0, 128, LWA_ALPHA); end; {设定计算器中的白色透明} procedure TForm1.Button2Click(Sender: TObject); var h: HWND; FormStyle: Integer; begin h := FindWindow('SciCalc', nil); FormStyle := GetWindowLong(h, GWL_EXSTYLE); SetWindowLong(h, GWL_EXSTYLE, FormStyle or WS_EX_LAYERED); SetLayeredWindowAttributes(h, clWhite, 255, LWA_COLORKEY); end; end.
posted on 2008-03-08 22:23  万一  阅读(13279)  评论(27编辑  收藏  举报