cwMessage-＞message == WM_ERASEBKGND )
{ //重画用户窗口
DrawBitmap(hClientHandle, hFaceBitmap, iClientHeight, iClientWidth);
}
}
if ( hMsgHook != NULL) //将消息继续下传
lReturn = CallNextHookEx(hMsgHook, nCode, wParam, lParam );
return lReturn;
} //卸载钩子函数
void __fastcall TMainForm::FormClose(TObject Sender, TCloseAction &&Action)
{ if ( hMsgHook != NULL)
UnhookWindowsHookEx( hMsgHook );
if ( Face != NULL )
delete Face;
}
//在指定的窗口中，画位图，填充整个用户窗口
//Ture为绘制成功，false为绘制失败
BOOL DrawBitmap(HWND Handle, HBITMAP hBitmap, int iClientHeight, int iClientWidth)
{ if ( hBitmap == NULL )
return false;
BITMAP b;
int iBitmapH, iBitmapW;
GetObject( hBitmap, sizeof( BITMAP), &&b);
iBitmapH = b.bmHeight;
iBitmapW = b.bmWidth;
int x, y;
HDC hClientDC, hMemDC;
hClientDC = GetDC(Handle);
if ( hClientDC == NULL )
return false;
hMemDC = CreateCompatibleDC( hClientDC );
if ( hMemDC == NULL )
{ DeleteDC( hClientDC );
return false;
}
SelectObject( hMemDC, hBitmap );
x = 0;
while ( x ＜ iClientWidth )
{ y = 0;
while ( y ＜ iClientHeight )
{ClientCanvas-＞Draw(x, y, Face);
BitBlt( hClientDC, x, y,iBitmapW, iBitmapH, hMemDC, 0, 0,SRCCOPY );
y = y + iBitmapH; }
x = x + iBitmapW; }
DeleteDC( hMemDC );
DeleteDC( hClientDC );
return true; }
将上述C++ Builder代码片段加入用户的MDI软件中即可实现任意的MDI程序背景图
……