I have an application whose data is in a file, which is represented in a explorer-like UI(a tree control on the left and a corresponding list control on the right, depending on the selected item in the tree control). I have the two standard menus, IDR_MAINFRAME and IDR_APPTYPE. Now, I want the IDR_APPTYPE menu to be displayed unless I choose File-Close. (but the window will still be open, I can open another file). But the problem is that when the last child window(last list view) is closed, the IDR_APPTYPE menu is gone, and replaced by IDR_MAINFRAME menu. How can I solve this problem?