You specify response to item in a response definition that is to be invoked when the user selects an item in an action bar. You can also specify that the response should be taken only for an item in a specific object or object class. (You can also specify the response to item statement in a response definition that is to be invoked when the user selects any member of an item class.)

When the item is selected, ESL responds by executing the action statements specified in the response definition. The response will be invoked only if the item is selectable (enabled) at the time that it is selected.