Vermont Views User Guide - Using Checkmarks in Menus - Using CHECKMARK() as the Action Function

Using CHECKMARK() as the Action Function

You can use the system action function if you simply want to toggle the checkmark for the selected menu field. Specify NULLP for the sub_fmp argument and CHECKMARK for the action_fp argument in the mnf_def() call, or set these parameters in the Designer.

When the user selects the menu field, the CHECKMARK() function is called. If the checkmark is displayed, the function changes the checkmark status to OFF. If the checkmark is not displayed, the function changes the checkmark status to ON. The menu processing function redisplays the menu appropriately.