Thread: Displaying a Bitmap

Ok, I have an MFC application with all my interface laid out. I have a CStatic control which I extended into the VideoProcessor class. I have a HBITMAP which I want to display. Now lets pretend, this HBITMAP is an image file (which in reality it isn't). In the OnPaint() function, I want to display this image.

I've spent 2 days trying to figure this out. I've read tutorial after tutorial, tried code chunk by code chunk. I can draw lines using the CPaintDC class but I can't BitBlt! I've tried to draw it on the parent form's paint event but with no luck either.

Here's my initialization:

Code:

videoBox.Create("", WS_CHILD | WS_VISIBLE | SS_BLACKFRAME, CRect(40, 40, 200, 160), this);

Note: I've also tried SS_BITMAP instead of SS_BLACKFRAME.

Code:

afx_msg void VideoProcessor::OnPaint()
{
   CPaintDC paint(this);
   HBITMAP bmp = ... ;
   int width = 160, height = 120;

   // draw bitmap here

   DeleteObject(bmp);
}

Please help, I can't believe I'm having so much trouble on such a trivial thing. No wonder people prefer C# or VB. But I *need* to draw this bitmap, asap! Thanks.

You should try to understand the tutuorials/references, instead of copy-n-pasting chunks of code from them.

Here is the OnPaint() of the attached code:

Code:

    // our paint DC
    CPaintDC dc(this);

    // load up our bitmap into bmME
    CBitmap cbmME;
    
    // for resources use:
    //    cbmME.LoadBitmap(IDB_BITMAP_ME);

    // for files use this:
    HBITMAP hBmp = (HBITMAP)::LoadImage(NULL, "avatar.bmp", IMAGE_BITMAP,
                                        0, 0, LR_LOADFROMFILE | LR_CREATEDIBSECTION);
    if (hBmp == NULL)
    {
        TRACE0("::LoadImage('avator.bmp') failed");
        return;
    }//if
   
    cbmME.Attach(hBmp);
    
    // use our hidden static frame for bitmap placement
    CRect framerect;
    GetDlgItem(IDC_STATIC_ME)->GetWindowRect(framerect);
    ScreenToClient(framerect);

    // create a memory DC
    CDC dcMem;
    dcMem.CreateCompatibleDC(&dc);

    // select the bitmap into the memory dc
    CBitmap *old = dcMem.SelectObject(&cbmME);

    // get the raw bitmap for access to its attributes
    BITMAP bm;
    cbmME.GetBitmap(&bm);

    // blit it
    dc.BitBlt(framerect.left, framerect.top, 
              bm.bmWidth, bm.bmHeight, 
              &dcMem, 0, 0, SRCCOPY);

    dcMem.SelectObject(old);
    ::DeleteObject(hBmp);

    CDialog::OnPaint();

gg

Wow, thanks so much! I was reading tutorials but I couldn't figure out what was wrong. I think its because I was getting the DC of the screen or something. Thanks for the code!