对话框中的菜单在禁止后无法恢复解决思路

对话框中的菜单在禁止后无法恢复
在下在对话框中弄了一个菜单，然后在代码中进行载入：

C/C++ code


    HMENU m_MainMenu;

C/C++ code


    m_MainMenu = LoadMenu(AfxGetInstanceHandle(), MAKEINTRESOURCE(IDR_MENU_MAIN));
    ::SetMenu(this->GetSafeHwnd(), m_MainMenu);

在对话框启动之后进行禁止操作：

C/C++ code


    CMenu *pMenu = CMenu::FromHandle(m_MainMenu);
    pMenu->EnableMenuItem(ID_MENU_SYS_MANAGE, MF_GRAYED);

禁止成功，此时打开菜单，相应的项为灰色。
然后当用户取得权限时我需要恢复该菜单项，于是我写入代码：

C/C++ code


    CMenu *pMenu = CMenu::FromHandle(m_MainMenu);
    pMenu->EnableMenuItem(ID_MENU_SYS_MANAGE, MF_ENABLED);

结果发现怎么都无法恢复。

我查阅了不少资料，有人说主要是对话框的更新UPDATE_COMMAND_UI消息问题。
http://blog.****.net/laiyiling/article/details/87027
http://support.microsoft.com/default.aspx?scid=kb;en-us;242577
于是我按照帖子所指示的，在对话框中加入了OnInitMenuPopup(CMenu *pPopupMenu, UINT nIndex,BOOL bSysMenu)代码：

C/C++ code


BEGIN_MESSAGE_MAP(CTestDlg, CDialog)
    ON_WM_INITMENUPOPUP()
END_MESSAGE_MAP()

C/C++ code


    ASSERT(pPopupMenu != NULL);
    // Check the enabled state of various menu items.

    CCmdUI state;
    state.m_pMenu = pPopupMenu;
    ASSERT(state.m_pOther == NULL);
    ASSERT(state.m_pParentMenu == NULL);

    // Determine if menu is popup in top-level menu and set m_pOther to
    // it if so (m_pParentMenu == NULL indicates that it is secondary popup).
    HMENU hParentMenu;
    if (AfxGetThreadState()->m_hTrackingMenu == pPopupMenu->m_hMenu)
        state.m_pParentMenu = pPopupMenu; // Parent == child for tracking popup.
    else if ((hParentMenu = ::GetMenu(m_hWnd)) != NULL)
    {
        CWnd* pParent = this;
        // Child windows don't have menus--need to go to the top!
        if (pParent != NULL &&
            (hParentMenu = ::GetMenu(pParent->m_hWnd)) != NULL)
        {
            int nIndexMax = ::GetMenuItemCount(hParentMenu);
            for (int nIndex = 0; nIndex < nIndexMax; nIndex++)
            {
                if (::GetSubMenu(hParentMenu, nIndex) == pPopupMenu->m_hMenu)
                {
                    // When popup is found, m_pParentMenu is containing menu.
                    state.m_pParentMenu = CMenu::FromHandle(hParentMenu);
                    break;
                }
            }
        }
    }

    state.m_nIndexMax = pPopupMenu->GetMenuItemCount();
    for (state.m_nIndex = 0; state.m_nIndex < state.m_nIndexMax;
        state.m_nIndex++)
    {
        state.m_nID = pPopupMenu->GetMenuItemID(state.m_nIndex);
        if (state.m_nID == 0)
            continue; // Menu separator or invalid cmd - ignore it.

        ASSERT(state.m_pOther == NULL);
        ASSERT(state.m_pMenu != NULL);
        if (state.m_nID == (UINT)-1)
        {
            // Possibly a popup menu, route to first item of that popup.
            state.m_pSubMenu = pPopupMenu->GetSubMenu(state.m_nIndex);
            if (state.m_pSubMenu == NULL ||
                (state.m_nID = state.m_pSubMenu->GetMenuItemID(0)) == 0 ||
                state.m_nID == (UINT)-1)
            {
                continue;    // First item of popup can't be routed to.
            }
            state.DoUpdate(this, TRUE); // Popups are never auto disabled.
        }
        else
        {
            // Normal menu item.
            // Auto enable/disable if frame window has m_bAutoMenuEnable
            // set and command is _not_ a system command.
            state.m_pSubMenu = NULL;
            state.DoUpdate(this, FALSE);
        }

        // Adjust for menu deletions and additions.
        UINT nCount = pPopupMenu->GetMenuItemCount();
        if (nCount < state.m_nIndexMax)
        {
            state.m_nIndex -= (state.m_nIndexMax - nCount);
            while (state.m_nIndex < nCount &&
                pPopupMenu->GetMenuItemID(state.m_nIndex) == state.m_nID)
            {
                state.m_nIndex++;
            }
        }
        state.m_nIndexMax = nCount;
    }

对话框中的菜单在禁止后无法恢复解决思路

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