A form controller is triggered either upon the form's submission or on adding or updating input in a form field. When a user adds or updates an input value in a form field or clicks the submit or cancel button in the form, the form function associated with this function is triggered to execute the intended action. There are three handlers associated with the form function:
- Submit Handler
- Dynamic Field Handler
- Change Handler
The submit handler is triggered on the form's submission. Data collected in the form will be available in the Submit Handler.
Dynamic Field Handler
The Dynamic field handler is triggered for the input field of type, dynamic_select. The handler auto-populates the drop-down menu items for the field based on the users' search query.
The change handler is triggered for an update made in any form field containing the boolean trigger_on_change as true. The change handler can be used to either add or remove fields in the form depending on the input made for a certain field.