8.4. Notification Events

Interaction events are raised as a result of explicit user action, for example, changing a value or navigating to a user interface control. In contrast, notification events are raised by the XForms processor to signal changes of state that require other processing steps to be initiated. Notification events provide a useful hook for XForms authors to attach custom behaviors. Below, we group these various notification events based on their function.

8.4.1. Setting Values

User input provided via XForms controls is finalized, that is, propagated to the bound instance when the user activates the control. The specific user action that activates a control varies, based on the user interface control as well as on the device in use. As an example, a desktop browser might use the pressing of the enter key to activate an input control. All such activation raises event DOMActivate, and this event provides a platform-neutral means for attaching custom behavior to be triggered when a control is activated. We used this event in attaching action 〈send〉 in Figure 7.1 to trigger an automatic lookup. This event is targeted at the user interface control to activate; the event can be canceled or allowed to bubble.