User`s guide

Add Code for Components in C allbacks
Menu Item
The G UIDE M enu Editor generates an empty callback subfunction for every
menu item, including menu titles.
Programming a Menu Title
Because clicking a menu title automatically displays the menu below it, you
may not need to program callbacks at the t itle lev el. However, th e callback
associatedwithamenutitlecanbeagoodplacetoenableordisablemenu
items below it.
Consider the example illustrated in the follow ing picture.
When a user selects the to file option under the Edit menu’s Copy option,
only the to file callback is required to perform the action.
Suppose, however, that only certain objects can be copied to a file. You can
use the Copy item
Callback callback to enable or disable the to file item,
depending on the type of object selected.
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