VC：对话框中菜单的使用（WM_INITMENUPOPUP）

1、在对话框资源上右击，在弹出的快捷菜单中选择Properties命令，弹出对话框里的Menu下拉列表框中选择IDR_MENU1.

2、添加响应COMMAND消息的映射函数。

3、添加UPDATE_COMMAND_UI消息，但此时对话框不能响应这个消息。添加WM_INITMENUPOPUP消息映射，其内部代码和MFC CFrameWnd::OnInitMenuPopup()内的代码相同。

具体如下：

Ctrl+W -->Classinfo -->MessageFilter下拉列表框中选择Window。返回到MessageMaps标签，添加WM_INITMENUPOPU

消息映射。

代码如下：

void CDialogMenuDlg::OnInitMenuPopup(CMenu* pPopupMenu, UINT nIndex, BOOL bSysMenu)

{

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

// TODO: Add your message handler code here

// CDialog::OnInitMenuPopup(pPopupMenu, nIndex, bSysMenu);

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;

}

}