//给MDI窗体加背景
//设置Form1窗体的FormStyle属性为fsMDIForm
//设置Form2窗体的FormStyle属性为fsMDIChild
// Image控件 Bmp格式图片
private
FClientInstance : TFarProc;
FPrevClientProc : TFarProc;
Procedure ClientWndProc(Var Message: TMessage);
procedure TForm1.ClientWndProc(var Message: TMessage);
var
Dc : hDC;
Row : Integer;
Col : Integer;
begin
with Message do
case Msg of
WM_ERASEBKGND://当要重会背景时
begin
Dc := TWMEraseBkGnd(Message).Dc;
// 铺图象
//计算并会制行和高总共要画的数量。
for Row := 0 to ClientHeight div Image1.Picture.Height do
for Col := 0 to ClientWidth div Image1.Picture.Width do
BitBlt(Dc,Col * Image1.Picture.Width,Row * Image1.Picture.Height
,Image1.Picture.Width,Image1.Picture.Height
,Image1.Picture.Bitmap.Canvas.Handle,0,0,SRCCOPY);
Result := 1;
end;
else // 传递其他消息
Result := CallWindowProc(FPrevClientProc,ClientHandle,Msg,wParam,lParam);
end;
end;
procedure TForm1.FormShow(Sender: TObject);
begin
FClientInstance := MakeObjectInstance(ClientWndProc);//将自定义过程的地址入口存入PClientInstance中
FPrevClientProc := Pointer(GetWindowLong(ClientHandle,GWL_WNDPROC));//记录消息位置
SetWindowLong(ClientHandle,GWL_WNDPROC,LongInt(FClientInstance));//重新载入窗口的消息并继续处理。
end;
//为非MDI窗体制作背景
