void CDemoDlg::OnPaint()
{
if (IsIconic())
{
CPaintDC dc(this); // 用于绘制的设备上下文
SendMessage(WM_ICONERASEBKGND, reinterpret_cast(dc.GetSafeHdc()), 0);
// 使图标在工作区矩形中居中
int cxIcon = GetSystemMetrics(SM_CXICON);
int cyIcon = GetSystemMetrics(SM_CYICON);
CRect rect;
GetClientRect(&rect);
int x = (rect.Width() - cxIcon + 1) / 2;
int y = (rect.Height() - cyIcon + 1) / 2;
// 绘制图标
dc.DrawIcon(x, y, m_hIcon);
}
else
{
if(x==0) //给第一个按钮设置标志，点打开按钮只在左边黑框里显示图片，要不然二个黑框里也会显示同一张图片
{
//ShowImage(pDC,strPathName1,0,0);
CPaintDC dc(this);
DrawImage(60,130,&dc);
}
else{
CPaintDC dc(this);
DrawImage(530,130,&dc);
}
CDialogEx::OnPaint();
}
//在屏幕上显示JPG图像
void CDemoDlg::DrawImage(int x, int y, CDC *pDC)
{
if (pPicture != NULL)
{
long nWidth,nHeight;
pPicture->get_Width( &nWidth );
pPicture->get_Height( &nHeight );
//图片原大显示
CSize sz( nWidth, nHeight );
pDC->HIMETRICtoDP( &sz );
pPicture->Render(pDC->m_hDC,x,y,sz.cx,sz.cy,0,nHeight,nWidth,-nHeight,NULL);
}
}
两个按钮处理程序都是调用Invalidate();显示
