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CWnd::GetIcon won't work

I have this chunk of code in my app
      if (hicon == NULL) {
            CWnd * p_wnd = AfxGetMainWnd();
            if (p_wnd != NULL)
                  hicon = p_wnd->GetIcon(TRUE);
      }

I traced it to the GetIcon call. It returns NULL. However, I use the m_hWnd member of p_wnd in SPY++ and the properties show me an icon handle. I know the icon handle is correct because I then used the debugging tools to plug in that icon handle (replacing the NULL) and it used the correct icon.

What am I doing wrong? How do I get this call to work?
Is there an alternate way of doing this?
Danny Pav

Bonev

Try p_wnd->GetIcon(FALSE);

Bonev

Try p_wnd->GetIcon(FALSE);

Bonev

In your CMainFrame::Create you will need to set the icon for that window.

danny_pav

ASKER

Bonev:
That can't be right. The correct icon is already displaying and from my original problem statement:

However, I use the m_hWnd member of p_wnd in SPY++ and the properties show me an icon handle. I know the icon handle is correct because I then used the debugging tools to plug in that icon handle (replacing the NULL) and it used the correct icon.

SPY++ recognizes the icon. Why does that function fail?

Bonev

danny_pav,
I wrote a sample app and I've run into the same problem.
When I put a SetIcon call in CMainFrame::Create everything went fine.
Basically, there are several things to do:
1. In InitInstance:
Check if the main frame is created and assigned to m_pMainWnd
2. In CMainFrame::Create:
call SetIcon(hIcon, FALSE); // if you need a big icon, use TRUE
3. In your function:
call GetIcon(FALSE); // the size should be the same as in 2

danny_pav

ASKER

Why do I have to do a SetIcon when the icon is already set? I can look at the screen to verify and I can use SPY to verify.

Bonev

Sure you need to set it - you cannot force the user to put the handle manually.

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Answers2000

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danny_pav

ASKER

I didn't think that would work with MFC. I figured that a only a few stock window classes were used and that would include stock icons as well (if any).

I still don't understand why GetIcon or WM_GETICON doesn't work. It seems to be not just a shortcoming of MFC.

Thanks, Bonev for the effort.
Thanks, Answers2000 for the answer.

Answers2000

>> I didn't think that would work with MFC.
I don't see why not

>> I figured that a only a few stock window classes were used and that would include stock icons as well (if any).
I was _strongly_ under the impression that MFC 4.2 generates strings and registers _multiple_ window classes (re-using same WndProcs). Older versions (I think) re-use the same classes.
You can read the sources and check on whichever MFC version you're using...Search for RegisterClass