怎样实现动画背景旗帜(2)

  VERIFY(m_bmpBackGround.GetObject(sizeof(bm), (LPVOID) &bm));
  dcMem.CreateCompatibleDC(NULL);
  CBitmap *pbmpOld = (CBitmap*)dcMem.SelectObject(&m_bmpBackGround);
  ASSERT(pbmpOld);
  // Display red background
  pDC->StretchBlt(0, 0, rect.right, rect.bottom, &dcMem, 0, 0, bm.bmWidth,
    bm.bmHeight, SRCCOPY);

  VERIFY(m_bmpBackGround2.GetObject(sizeof(bm2), (LPVOID) &bm2));
  dcMem2.CreateCompatibleDC(NULL);
  dcMem2.SelectObject(&m_bmpBackGround2);
  // Display picture background
  pDC->StretchBlt(200, 100, 400, 200, &dcMem2, 0, 0, bm2.bmWidth, bm2.bmHeight,
    SRCCOPY);

  // Display Instructions
  pDC->SetBkColor(RGB(255, 0, 0));
  pDC->SetTextColor(RGB(192, 192, 192));
  pDC->TextOut(480, 500, "Mouse Right Click to Stop/Start Special Effects");
  pDC->TextOut(480, 515, "Mouse Left-Click to Show Child Window");

  // CleanUp
  dcMem.SelectObject(pbmpOld);

  return TRUE;
}

////////////////////////////////////////////////////////////////////
//
void CMdiMainClient::OnSize(UINT nType, int cx, int cy)
{
  Default();
  // if the app is just starting up, save the window
  // dimensions and get out

  if ((m_sizeClient.cx == 0) && (m_sizeClient.cy == 0))
  {
    m_sizeClient.cx = cx;
    m_sizeClient.cy = cy;

    return ;
  }

  // if the size hasn't changed, break and pass to default

  if ((m_sizeClient.cx == cx) && (m_sizeClient.cy == cy))
  {
    return ;
  }

  // window size has changed so save new dimensions and force
  // entire background to redraw, including icon backgrounds

  m_sizeClient.cx = cx;
  m_sizeClient.cy = cy;

  RedrawWindow(NULL, NULL, RDW_INVALIDATE | RDW_ERASE | RDW_ERASENOW |
    RDW_ALLCHILDREN);