You will also learn how to associate a button with a list of values that you create. Now that we got a button, we want the button to do some thing when the user presses it. We must associate a trigger with the button. The word trigger means any device that activates some other mechanism. A trigger recognizes the occurrence of an event and its used to conditionally perform certain actions.
Triggers are parcels of logic placed strategically at event points throughout the form.
An operator running a form loaded with triggers is bound to encounter the effects of one or two at the form, block, and field levels. When this occurs, the trigger is activated and the contents of the trigger special rules or instructions written by the designer are executed. For example, an operator may enter a product ID that is incorrect. A trigger could be defined at this event point, and be activated whenever the operator leaves this field after entering a value. The trigger logic could check for an existing product and if the product exists to fill in the remainder of information to save the operator from filling in any more information.