Let's turn first to the MDIDEMO.RC resource script. The resource script defines three menu templates used by the program.
The program displays the MdiMenuInit menu when no document windows are present. This menu simply allows creating a new document or exiting the program.
The MdiMenuHello menu is associated with the document window that displays ”Hello, World!“ The File submenu allows opening a new document of either type, closing the active document, and exiting the program. The Color submenu lets you set the text color. The Window submenu has options for arranging the document windows in a cascaded or tiled fashion, arranging the document icons, and closing all the windows. This submenu will also list all the document windows as they are created.
The MdiMenuRect menu is associated with the random rectangle document. This is the same as the MdiMenuHello menu except that it does not include the Color submenu.
The MDIDEMO.H header file defines all the menu identifiers as well as three constants:
#define INIT_MENU_POS 0
#define HELLO_MENU_POS 2
#define RECT_MENU_POS 1
These identifiers indicate the position of the Window submenu in each of the three menu templates. This information is needed by the program to inform the client window where the document list is to appear. Of course, the MdiMenuInit menu doesn't have a Window submenu, so I've indicated that the list should be appended to the first submenu (position 0). The list will never actually be viewed there, however. (You'll see why this is needed when I discuss the program later.)
The IDM_FIRSTCHILD identifier doesn't correspond to a menu item. This is the identifier that will be associated with the first document window in the list that will appear in the Window submenu. You should choose this identifier to be greater than all the other menu IDs.