Problem with SDI CView covered with bitmap resource

I have an SDI / CView app (VS 2010). All works well until I minimize the app using the minimize button or drag it partially off of the screen. In the former instance, any attempt to restore the app results in an appcrash with a tight freeze up of the machine. In the later instance the same happens immediately.

In building the app, I scoured the web for code to accomplish the loading and display of the bitmap. After some experimentation I settled on overriding the OnPaint. Below is the code. Note that m_Map is a CBitmap member and IDB_BITMAP1 is a loaded bitmap resource.

Code:

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 void CMyDragViewView::OnPaint()
 {
        // CPaintDC dc(this); // device context for painting
        // TODO: Add your message handler code here
        // Do not call CView::OnPaint() for painting messages

        // http://msgroups.net/microsoft.public.vc.mfc/loading-bitmaps-into-main-window/563285
        int x = m_Map.LoadBitmap(IDB_BITMAP1);
        TRACE1(" x = %d\n", x);
        CPaintDC* dc = new CPaintDC(this);
        CDC cdc;
        cdc.CreateCompatibleDC(dc);
        CBitmap* pOldBitmap = cdc.SelectObject(&m_Map);
        BITMAP MapInfo;
        m_Map.GetObject(sizeof(MapInfo), &MapInfo);
        dc->BitBlt(0, 0, MapInfo.bmWidth, MapInfo.bmHeight, &cdc, 0, 0, SRCCOPY);

        cdc.SelectObject(pOldBitmap);

 }

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I suspect that the problem is OnPaint trying to repaint the bitmap which requires reloading it, but I don't know how to work around this.

Any help greatly appreciated.

Quote:

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Originally Posted by Mike Pliam

Code:

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void CMyDragViewView::OnPaint()
 {
        // CPaintDC dc(this); // device context for painting
        // TODO: Add your message handler code here
        // Do not call CView::OnPaint() for painting messages

        // http://msgroups.net/microsoft.public.vc.mfc/loading-bitmaps-into-main-window/563285
        int x = m_Map.LoadBitmap(IDB_BITMAP1);
        TRACE1(" x = %d\n", x);
        CPaintDC* dc = new CPaintDC(this);
        CDC cdc;
        cdc.CreateCompatibleDC(dc);
        CBitmap* pOldBitmap = cdc.SelectObject(&m_Map);
        BITMAP MapInfo;
        m_Map.GetObject(sizeof(MapInfo), &MapInfo);
        dc->BitBlt(0, 0, MapInfo.bmWidth, MapInfo.bmHeight, &cdc, 0, 0, SRCCOPY);

        cdc.SelectObject(pOldBitmap);
 }

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I suspect that the problem is OnPaint trying to repaint the bitmap which requires reloading it, but I don't know how to work around this.

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Mike, I don't understand your problem with "minimize the app" but your code produces a series of memory leaks!
Why do you create CPaintDC instance in the heap? :confused:
Why don't you free it? :confused:

Mike, you're not an absolute beginner here on the forum. So I do not understand why you prefer asking elementary questions along with descriptions that explain nothing instead of trivial modelling your problem in a standalone app, and posting it here in case the problem remains. This is not the first time when you get real help this and only this way. Please see the working sample and compare it with your code.

Victor, I am clearly not experienced in building custom MFC interfaces as I have spent most of my efforts in dealing with mathematical and statistical code underlying my applications, so in that sense, I am very much a beginner when it comes to interfaces. Igor, your point is well taken and I respect it. I apologize for not posting a demo app but yours works beautifully. Once again I am greatly indebted to you both and to Codeguru from whence most of my programming knowledge has come from. Thank you both.