The base menu is the menu that is initially loaded with AutoCAD LT. In AutoCAD LT, this file is aclt.mnc. The term base menu refers to a complete menu description and usually contains button, image, and other sections as well as the pull-down menu definitions found in the section labeled POPn. If there is an associated menu resource file (DLL), the resources in that file are loaded.
You can load partial menus and modify the menu bar with the MENULOAD Menu Customization dialog box in which multiple partial menu files and specific base files work together. With MENULOAD, you load a partial menu and then add and rearrange the pull-down menus on the menu bar. This allows you to make effective use of multiple menu files.
AutoCAD LT enforces strict menu group definitions; no two menus can define the same menu group. If you attempt to load a menu with a conflicting menu group, the MENULOAD request is canceled.
Use the PREFERENCES Files tab to specify a new menu, and MENULOAD and MENUUNLOAD to load and unload partial menus and add or remove individual pull-down menus from the menu bar.
AutoCAD LT stores the name of the last loaded menu in the system registry. This name is also saved with the drawing, but it is used only for backwards compatibility. When you start AutoCAD LT, the last menu used is loaded. As of AutoCAD LT 97, AutoCAD LT no longer reloads the menu between drawings.
AutoCAD LT finds and loads the specified file according to the following sequence. This same sequence is used when AutoCAD LT loads a new menu.
Each time AutoCAD LT compiles an MNC file it generates a menu resource (MNR) file, which contains the bitmaps used by the menu. The MNS file is an ASCII file that is initially the same as the MNU file (without comments or special formatting). The MNS file is modified by AutoCAD LT each time you make changes to the contents of the menu file through the interface (such as modifying the contents of a toolbar).
Although the initial positioning of the toolbars is defined in the MNU or MNS file, changes to the show/hide and docked/floating status or changes to the toolbar positions are recorded in the system registry. After an MNS file has been created, it is used as the source for generating future MNC and MNR files. If you modify the MNU file after an MNS file has been generated, you must use the PREFERENCES command to explicitly load the MNU file so that AutoCAD LT will generate new menu files and your changes will be recognized.
Note: If you use the interface to modify the toolbars, you should cut and paste the modified portions of the MNS file to the MNU file before deleting the MNS file.
With partial menus, AutoCAD LT provides a convenient method for referencing specific menu items from several menu files. Each menu item is assigned a name tag, and each menu file is assigned a menu group name. By specifying a menu group name and name tag, you can add and remove any menu item.
Frequent changes to the contents of a menu bar can confuse the user. It is not recommended that you change the state of the menu bar visually except on explicit request from the user. For example, if a user wants to unload an application, menus referenced specifically by that application could be removed as well.
The menu could also be completely reinitialized, removing all partial menus currently loaded, by executing MENULOAD and loading a new base menu file by checking Replace All in the Menu Customization dialog box. This procedure removes all partial menus as well as their associated tag definitions and is equivalent to specifying a new menu file in the Files tab of the Preferences dialog box.
You can use a customized menu for some tasks while keeping the standard menu easily available. To load your custom menu, on the File System tab of the Preferences dialog box, enter the custom menu name next to Menu File.
When you use MENULOAD or MENUUNLOAD to alter the loaded menus or customize the menu bar with Pop and Toolbar menus, the changes are saved to the registry. The next time you start up AutoCAD LT, the menus that were loaded last and the menu bar configuration are restored. You can load and unload up to 8 partial menus and up to 16 Pop menus.