如何在 win32/mfc 应用程序中隐藏/折叠主菜单

void CMainFrame::OnHideMenu()
{
    SetMenu(NULL);
}

void CMainFrame::OnToggleMenu()
{
    CMenu* pMenu = GetMenu();
    if (pMenu != NULL)
    {
        UINT uState = pMenu->GetMenuState(ID_FILE_EXIT, MF_BYCOMMAND);
        if (uState & MF_CHECKED)
        {
            pMenu->CheckMenuItem(ID_FILE_EXIT, MF_BYCOMMAND | MF_UNCHECKED);
            SetMenu(NULL);
        }
        else
        {
            pMenu->CheckMenuItem(ID_FILE_EXIT, MF_BYCOMMAND | MF_CHECKED);
            SetMenu(pMenu);
        }
    }
}

void CMainFrame::OnHideMenu()
{
    CMenu* pMenu = GetMenu();
    if (pMenu != NULL)
    {
        pMenu->ShowWindow(SW_HIDE);
    }
}

void CMainFrame::OnHideMenuItem()
{
    CMenu* pMenu = GetMenu();
    if (pMenu != NULL)
    {
        pMenu->ModifyMenu(0, MF_BYPOSITION | MF_HIDDEN, NULL);
    }
}