hi, i am an experienced C++ and WinAPI programmer, but this is my first experience with MFC and VisualC++. I tried to add ActiveX controls like a WebBrowser or a RichEdit Control to a dialog that is called in CWinApp::InitInstance in response to the EndDialog(1) call on a first, signon dialog. However, I get an assertion failure in void*& CMapPtrToPtr::operator[](void* key) in map_pp.cpp. The dialog works fine without the controls. what could be causing this and how can I fix it? please help.

If you haven't already done so, try isolating one control at a time, and seeing which is the culprit, if not both. The failed assertion is probably for:

ASSERT_VALID(this);

This suggests that an instance of CMapPtrToPtr is not valid (but not necessarily NULL; look at what AfxAssertValidObject checks, which is how ASSERT_VALID is #defined). Trace back on the call stack to where the subscript operator is first used on your CMapPtrToPtr object, to get a better idea of what's wrong.

You never mentioned how you were incorporating the controls into your project, and that might provide further clues. Also, which version of VC and the controls?

The error is caused by a failed assertion, marked below. This is in response to some message, exactly which one i have been unable to determine. I am using VC++ 6.0 and have a dialog-based app with all controls added to the dialog graphically in resources. the relevant callstack is pasted below the following code. Also, i was pleasantly surprised by the speed with which you responded to my question. Thank you very much.

LRESULT CALLBACK
AfxWndProc(HWND hWnd, UINT nMsg, WPARAM wParam, LPARAM lParam)
{
// special message which identifies the window as using AfxWndProc
if (nMsg == WM_QUERYAFXWNDPROC)
return 1;

// all other messages route through message map
CWnd* pWnd = CWnd::FromHandlePermanent(hWnd);
///////////////////////////////////////////
//following assertion of pWnd fails
ASSERT(pWnd != NULL);
ASSERT(pWnd->m_hWnd == hWnd);
return AfxCallWndProc(pWnd, hWnd, nMsg, wParam, lParam);
}

NTDLL! 77f7f570()
_CrtDbgReport(int 0x00000002, const char * 0x5f4cccf0 THIS_FILE, int 0x0000016d, const char * 0x00000000, const char * 0x00000000) line 353
AfxAssertFailedLine(const char * 0x5f4cccf0 THIS_FILE, int 0x0000016d) line 39 + 20 bytes
AfxWndProc(HWND__ * 0x0010036c, unsigned int 0x0000001f, unsigned int 0x00000000, long 0x00000000) line 365 + 21 bytes
AfxWndProcBase(HWND__ * 0x0010036c, unsigned int 0x0000001f, unsigned int 0x00000000, long 0x00000000) line 220 + 21 bytes

The problem is not at that point, but earlier somewhere. The failing assertion is only saying that FromHandlePermanent was not able to find a CWnd object for the hWnd passed into the window procedure (not a recognised MFC handle in your app). Did you try removing each control and seeing which one causes problems?

The message is WM_CANCELMODE (0x1F), according to the trace. It is probably related to the dialog opening. Without knowing how the controls are integrated into the app, it is difficult to know why the handle is unknown to the app. Do the controls have any message map entries (look below BEGIN_MESSAGE_MAP macro)?

thank you for all of your help. I overrode the OnCancelMode handler and did not call CDialog::OnCancelMode and the dialog works fine. i don't know what cancel mode does, but it doesnt seem to be affecting the application. i have an OnBnClicked for one button in the dialog.

Glad to hear it. I don't think you'll miss OnCancelMode, since its main purpose is just to give the window underneath the new dialog, a chance to cancel special stuff like if mouse-capturing was set for it. 99% of situations probably never need it.

Cheers