FIX: AfxMessageBox Help Fails to Bring Up Proper Topic (229964)

RESOLUTION

#include "afxpriv.h"
...

int CHelpApp::DoMessageBox(LPCTSTR lpszPrompt, UINT nType, UINT nIDPrompt) 
{
	// disable windows for modal dialog
	EnableModeless(FALSE);
	HWND hWndTop;
	HWND hWnd = CWnd::GetSafeOwner_(NULL, &hWndTop);

	// set help context if possible
	DWORD* pdwContext = NULL;
	HWND hWnd2 = AfxGetMainWnd()->GetSafeHwnd();
	if (hWnd2 != NULL)
	{
		// use app-level context or frame level context
		LRESULT lResult = ::SendMessage(hWnd2, WM_HELPPROMPTADDR, 0, 0); // Use "MainWnd" HWND
		if (lResult != 0)
			pdwContext = (DWORD*)lResult;
	}
	// for backward compatibility use app context if possible
	if (pdwContext == NULL && this != NULL)
		pdwContext = &m_dwPromptContext;

	DWORD dwOldPromptContext = 0;
	if (pdwContext != NULL)
	{
		// save old prompt context for restoration later
		dwOldPromptContext = *pdwContext;
		if (nIDPrompt != 0)
			*pdwContext = HID_BASE_PROMPT+nIDPrompt;
	}

	// determine icon based on type specified
	if ((nType & MB_ICONMASK) == 0)
	{
		switch (nType & MB_TYPEMASK)
		{
		case MB_OK:
		case MB_OKCANCEL:
			nType |= MB_ICONEXCLAMATION;
			break;

		case MB_YESNO:
		case MB_YESNOCANCEL:
			nType |= MB_ICONEXCLAMATION;
			break;

		case MB_ABORTRETRYIGNORE:
		case MB_RETRYCANCEL:
			// No default icon for these types, since they are rarely used.
			// The caller should specify the icon.
			break;
		}
	}

#ifdef _DEBUG
	if ((nType & MB_ICONMASK) == 0)
		TRACE0("Warning: no icon specified for message box.\n");
#endif

	TCHAR szAppName[_MAX_PATH];
	LPCTSTR pszAppName;
	if (this != NULL)
		pszAppName = m_pszAppName;
	else
	{
		pszAppName = szAppName;
		GetModuleFileName(NULL, szAppName, _MAX_PATH);
	}

	int nResult =
		::MessageBox(hWnd, lpszPrompt, pszAppName, nType);

	// restore prompt context if possible
	if (pdwContext != NULL)
		*pdwContext = dwOldPromptContext;

	// re-enable windows
	if (hWndTop != NULL)
		::EnableWindow(hWndTop, TRUE);
	EnableModeless(TRUE);

	return nResult;
}