1、為頁面（窗口）添加一個(gè)菜單欄和子菜單

2、在XXDlg.h文件中定義一個(gè)菜單欄變量和bool變量

CMenu m_Menu;	//菜單變量
bool m_EnableMenu;//菜單欄中某個(gè)子菜單禁用/啟用（變灰）的控制變量

3、在OnInitDialog函數(shù)中進(jìn)行初始化：（即將菜單欄植入主界面）

m_Menu.LoadMenu(IDR_MENU_MAIN);//菜單欄的ID
SetMenu(&m_Menu);//添加入到界面
m_EnableMenu =false;//初始化為禁用子菜單

4、添加菜單ID的ON_UPDATE_COMMAND_UI消息，點(diǎn)擊菜單，在子菜單上右鍵點(diǎn)擊，添加事件處理程序，選擇你的對話框類，在左邊的消息類型中選擇UPDATE_COMMAND_UI添加如下代碼：

void CXXDlg::OnUpdateDisconnectAll(CCmdUI *pCmdUI)
{
	pCmdUI->Enable(m_EnableMenu); //m_EnableMenu的值對應(yīng)禁用和啟用，1是啟用，0是禁用
} 

根據(jù)網(wǎng)上資料，對于視圖文檔類MFC程序，在主框架類CMainFrame的構(gòu)造函數(shù)中把成員變量m_bAutoMenuEnable=FALSE就可以解決問題了。但是基于對話框的MFC應(yīng)用程序沒有m_bAutoMenuEnable變量。解決方法：

5、在對話框類的消息中加入OnInitMenuPopup（）消息：

消息函數(shù)內(nèi)重載如下：

void CXXXDlg::OnInitMenuPopup(CMenu* pPopupMenu, UINT nIndex, BOOL bSysMenu)
{
     CDialog::OnInitMenuPopup(pPopupMenu, nIndex, bSysMenu);

   	// TODO: 在此處添加消息處理程序代碼
   
	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;
	}
}

如果想在其他程序中改變菜單的啟用/禁用屬性，改變m_EnableMenu的值即可實(shí)現(xiàn)。文章來源地址http://www.zghlxwxcb.cn/news/detail-733124.html

到了這里，關(guān)于MFC 如何啟用/禁用菜單（返灰/不可點(diǎn)擊狀態(tài)）的文章就介紹完了。如果您還想了解更多內(nèi)容，請?jiān)谟疑辖撬阉鱐OY模板網(wǎng)以前的文章或繼續(xù)瀏覽下面的相關(guān)文章，希望大家以后多多支持TOY模板網(wǎng)！