delphi 程序最小化和最大化都不在任务栏显示

delphi   程序不在任务栏显示

published
procedure CreateParams( var Params: TCreateParams ); override;
procedure WndProc(var Message: TMessage); override;

procedure TmainFrm.CreateParams( var Params: TCreateParams );
begin
inherited CreateParams( Params );
Params.ExStyle := WS_EX_TOOLWINDOW;
end;

procedure TmainFrm.WndProc(var Message: TMessage);
begin
inherited WndProc(Message);
if (not Application.MainFormOnTaskBar) and (Message.Msg = WM_SHOWWINDOW) then
begin
ShowWindow(Application.Handle, SW_HIDE);
SetWindowLong(Application.Handle, GWL_EXSTYLE, WS_EX_TOOLWINDOW);
end;
end;

 上面的方法 在桌面上会显示一个小窗口

另外的方式  

procedure WMSysCommand(var Message: TWMSysCommand);message WM_SYSCOMMAND;


//如果是关闭或者最小化  不显示主窗口
procedure TmainFrm.WMSysCommand(var Message: TWMSysCommand);
begin
  if (Message.CmdType  = SC_MINIMIZE) or (Message.CmdType  = SC_CLOSE) then
    Self.Visible:=False // 隐藏窗体
  else
    Inherited;
end;

//双击右下角 小图标 显示出来

Self.Visible:=true// 隐藏窗体