FIX: OnInitMenuPopup Deletes Temporary Objects

MORE INFORMATION

MFC maintains a map from handles such as HMENUs to their C++ wrapper objects. When a call is made to, for example, GetMenu, MFC attempts to find the C++ wrapper object that corresponds to the HMENU ::GetMenu returns. If no object in the permanent map is found, MFC creates a temporary object that is normally destroyed in OnIdle processing by a call to AfxUnlockTempMaps.

Sample Code to Reproduce or Resolve Problem

/* Compile options needed: default
*/ 

// Use this code to fix the problem:
void CMainFrame::OnInitMenuPopup(CMenu* pPopupMenu, UINT nIndex,
                                                   BOOL bSysMenu)

{
    #if _MFC_VER == 0x400
    AfxLockTempMaps();
    #endif

    CMDIFrameWnd::OnInitMenuPopup(pPopupMenu, nIndex, bSysMenu);

    // TODO: Add your message handler code here

    #if _MFC_VER == 0x400
    AfxUnlockTempMaps();
    #endif

}

				

// Use the following code to reproduce the problem in an MDI application:
void CMainFrame::OnInitMenuPopup(CMenu* pPopupMenu, UINT nIndex,
                                                   BOOL bSysMenu)

{

    CMDIFrameWnd::OnInitMenuPopup(pPopupMenu, nIndex, bSysMenu);

    // The next line will cause an ASSERT on line 1034 in a debug
    // build because pPopupMenu is an invalid pointer
    pPopupMenu->CheckMenuItem(0, MF_BYPOSITION | MF_CHECKED);

}