1）当我们把QQ

1）当我们把QQ
  主窗体拖到桌面顶部后，放开鼠标，他就会自动
  缩上去，鼠标移到他身上时又会重新出现！
   请问谁有研究过教我一下吧？
我写了但没有用：
procedure TForm1.CMMouseEnter(var message: TMessage);
begin
{if top=-17 then
begin//2
Height:=65 ;
SetCapture(Handle);
end;//2     // 激活窗口
}
 case Message.Msg of
    CM_MOUSEENTER:begin
                     SetCapture(Handle);
                     if Self.Height <= 0 then
                        self.Height := 30;
                     self.Invalidate;
                  end;
    end;
end;procedure TForm1.CMMouseLeave(var Message: TMessage);
//var
//  Pt: TPoint;
begin
  {GetCursorPos(Pt);
  if not PtInRect(Bounds(Left, Top, Width, Height), Pt)
  then  // 做此判断为过滤
  begin//1
   if top=-17 then
   begin//2
    Height:=1;
    ReleaseCapture;
   end;//2
   end;//1
  }
 case Message.Msg of
     CM_MOUSELEAVE: begin                      if self.Height > 30 then
                        self.Height := 0;
                      self.Invalidate;
                      ReleaseCapture;
                    end;     end;
end;procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
if Button= mbLeft then
begin
ReleaseCapture;
SendMessage(Handle , WM_NCLBUTTONDOWN, HTCAPTION, 0);end;
end;procedure TForm1.FormCreate(Sender: TObject);
begin
top:=-17;
left:=300;
height:=30;
end;procedure TForm1.FormMouseUp(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
if top<0 then
   top:=-100;
end;