2.導入背景位圖IDB_CAR
3.添加新的類CBgWnd。基類選擇generic CWnd類。
4.重載CBgWnd類的OnEraseBkgnd(CDC *pDC)函數。
BOOL CBgWnd::OnEraseBkgnd(CDC* pDC)
{
// TODO: Add your message handler code here and/or call default
CDC memDc;
CBitmap bmp;
CRect clientRect;
BITMAP bitmap;
GetClientRect(&clientRect);
bmp.LoadBitmap(IDB_CAR);
bmp.GetObject(sizeof(BITMAP), &bitmap);
memDc.CreateCompatibleDC(pDC);
CBitmap *pOldBmp = memDc.SelectObject(&bmp);
pDC->StretchBlt(clientRect.left, clientRect.top, clientRect.Width(), clientRect.Height(), &memDc, 0, 0, bitmap.bmWidth, bitmap.bmHeight, SRCCOPY);
memDc.SelectObject(pOldBmp);
memDc.DeleteDC();
return TRUE;
//return CWnd::OnEraseBkgnd(pDC);
}
5.重載CBgWnd類的OnSize(UINT nType, int cx, int cy) 函數。
void CBgWnd::OnSize(UINT nType, int cx, int cy)
{
CWnd::OnSize(nType, cx, cy);
// TODO: Add your message handler code here
Invalidate();
}
6.在CMainFrame類中添加CBgWnd類型變量。
CBgWnd m_bgWnd;
7.在CMainFrame類OnCreate函數中添加
if (!m_bgWnd.SubclassWindow(m_hWndMDIClient))
{
return -1;
}