Menus - dynamic menu creation

Problem:

You need to write menus that will change (dynamic menus) if you change the content of a file, without recompiling the program.

Resolution:

Attached to this KB article is an AcuBench demo project that contains sample code for creating dynamic menus, and a sample file for testing. The important parts of the code are described below.

Read a file and create the level and the branches needed for your menu. The demo project uses the following code to accomplish this:

Screen1-Aft-Initdata.           open input filemenu/* Create a new menu */           call "w$menu" using wmenu-new giving menu-handle           if menu-handle = zero               go to acu-menudina-mn-1-exit           end-if                      move low-values to filemenu-exception           start filemenu key is greater than filemenu-exception           read filemenu next record           perform until not Valid-filemenu                              evaluate filemenu-level                   when 1                       perform acu-level1-add-branch                   when 2                       perform acu-level2-add-element               end-evaluate               read filemenu next record           end-perform           move menu-handle to Screen1-menu-handle/* show the menu */           call "w$menu" using wmenu-show, Screen1-menu-handle           close filemenu           .       Acu-menudina-mn-1-exit.           move zero to return-code           ./* Create a new branch */       Acu-submenu-routine.           call "w$menu" using wmenu-new giving sub-handle-1           if sub-handle-1 = zero               move zero to menu-handle               go to acu-menudina-mn-1-exit           end-if           .       acu-level1-add-branch.           perform Acu-submenu-routine/* Add first element to a new branch. */           call "w$menu" using wmenu-add, menu-handle, 0, 0,                filemenu-name, filemenu-exception, sub-handle-1           ./* Add a new element to an existing branch. */       acu-level2-add-element.           call "w$menu" using wmenu-add, sub-handle-1, 0, 0,                filemenu-name, filemenu-exception           .

Add the code to handle the click on the menu:

Screen1-Ex-Other.           open input filemenu           move key-status to filemenu-exception           start filemenu key is equal filemenu-exception               read filemenu           if Valid-filemenu               display message box filemenu-name           end-if           close filemenu           .

This example uses the following file structure:

       FD  filemenu.       01 filemenu-rec.           05 filemenu-name       PIC  x(40).           05 filemenu-level      PIC  9.           05 filemenu-program    PIC  x(20).           05 filemenu-exception  PIC  9(4).

Filemenu-nameis the name of entry on the menu.

Filename-levelcan be:

1. New branch
2. New element of the same branch

Filemenu-programis the name of the program we want to call.

Filemenu-exceptionis the value of the exception attached to that menu choice. It is the key to recover the program to be called (when the menu is chosen this is the value we recover). In this demo, this value is also used to recover the order of creation of branches and elements.

This is everything you need to control a small dynamic menu.

Incident Number: none