用MFC的消息映像实现动态菜单(3)

　　在头文件的类声明中：

BOOL m_bItemOne, m_bItemTwo, m_bPopupOne, m_bPopupTwo;
//用于决定各个菜单项的状态
protected:
afx_msg void OnUpdateMenuitemOne(CCmdUI* pCmdUI);
afx_msg void OnUpdateMenuitemTwo(CCmdUI* pCmdUI);
afx_msg void OnUpdatePopupOne(CCmdUI* pCmdUI);
afx_msg void OnUpdatePopupTwo(CCmdUI* pCmdUI);
//各菜单项的更新函数
DECLARE_MESSAGE_MAP()
　　在源文件中：

BEGIN_MESSAGE_MAP(CMyDoc, CDocument)
ON_UPDATE_COMMAND_UI (ID_ITEM_ONE,
OnUpdateMenuitemOne)
ON_UPDATE_COMMAND_UI (ID_ITEM_TWO,
OnUpdateMenuitemTwo)
ON_UPDATE_COMMAND_UI (ID_POPUP_ONE,
OnUpdatePopupOne)
ON_UPDATE_COMMAND_UI (ID_ POPUP_TWO,
OnUpdatePopupTwo)
END_MESSAGE_MAP()
void CMyApp::OnUpdatetMenuitemOne (CCmdUI* pCmdUI)
{
pCmdUI->Enable(m_bItemOne);
if(m_bItemOne) pCmdUI->SetText("Item One");
else pCmdUI->SetText("Item One is now disabled");
}
void CMyApp::OnUpdatetMenuitemTwo (CCmdUI* pCmdUI)
{
pCmdUI->Enable(m_bItemTwo);
if(m_bItemTwo) pCmdUI->SetText("Item Two");
else pCmdUI->SetText("Item Two is now disabled");
}
void CMyApp::OnUpdatePopupOne(CCmdUI* pCmdUI)
{
if (pCmdUI->m_pSubMenu != NULL)
{
BOOL b_Popup = m_bPopupOne || m_bPopupTwo;
pCmdUI->m_pMenu->EnableMenuItem(pCmdUI->m_nIndex,
MF_BYPOSITION |
(bEnable ? MF_ENABLED :
(MF_DISABLED | MF_GRAYED)));
return;
}
pCmdUI->Enable(m_bPopupOne);
}
void CMyApp::OnUpdatePopupTwo(CCmdUI* pCmdUI)
{
pCmdUI->Enable(m_bPopupTwo);
}