help:update_command_ui

[happycpp]

hi everyone.. i have a little problem with UPDATE_COMMAND_UI...it seems to work perfectly in non-dialog based programs but when it comes to dialog-based ones the following are noticed: 1-the OnUpdateFileNew function(which is called by the ON_UPDATE_COMMAND_UI) is not called until my menu item is pressed...it should be called before the item is displayed.. 2-the CCmdUI* in the previous function belongs to a weird class called CTestCmdUI which is in wincore.cpp...it should be a pointer to a CCmdUI class in cmdtarg.cpp.... actually i'm new in this update command ui thing so it will be very appreciated to explain more about it to me... thanx..

[Jose Lamas Rios]

MFC doesn't implement the automatic update of UI elements for dialog based apps. If you want to have this functionality for a menu in a dialog based application you could do something like the following (it wasn't thoroughly tested and makes use of undocumented functions so, as always, use it at your own risk): In you dialog class declaration, add the following member: afx_msg void OnInitMenuPopup(CMenu* pMenu, UINT nIndex, BOOL bSysMenu); In your dialog's cpp file, make the following changes (change "YourDialog" to the actual class name of your dialog too):

BEGIN_MESSAGE_MAP(YourDialog, CDialog)
   // what you already have
   // [...]
 
   // Add this:
   ON_WM_INITMENUPOPUP()
END_MESSAGE_MAP()
 
void AFXAPI AfxCancelModes(HWND hWndRcvr);
 
void YourDialog::OnInitMenuPopup(CMenu* pMenu, UINT nIndex, BOOL bSysMenu)
{
   AfxCancelModes(m_hWnd);
 
   if (bSysMenu)
      return; // don't support system menu
 
   ENSURE_VALID(pMenu);
 
   // check the enabled state of various menu items
 
   CCmdUI state;
   state.m_pMenu = pMenu;
   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 == pMenu->m_hMenu)
      state.m_pParentMenu = pMenu; // parent == child for tracking popup
   else if ((hParentMenu = ::GetMenu(m_hWnd)) != NULL)
   {
      CWnd* pParent = GetTopLevelParent();
         // 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 nItemIndex = 0; nItemIndex < nIndexMax; nItemIndex++)