Appendix B: Changes

Editor:: Philippe Le Hégaret, W3C

B.1 Changes between DOM Level 2 Events and DOM Level 3 Events

This new specification provides a better separation between the DOM event flow, the event types, and the DOM interfaces.

B.1.1 Changes to DOM Level 2 event flow

This new specification introduced two new concepts in the event flow:

event groups: unlike DOM Level 2 Events, Event.stopPropagation() does no longer stop the event propagation entirely. It only stops it for a given event group.
partial ordering of event listeners: within an event group, event listeners are now ordered while ordering was unspecified in DOM Level 2 Events.

B.1.2 Changes to DOM Level 2 event types

Lots of clarifications have been made on the event types. The conformance is now explicitly defined against the event types, and not only in terms of interfaces required by the event types. Support for namespaces and the features "BasicEvents", "TextEvents", "KeyboardEvents", and "MutationNameEvents" have been introduced.

The DOM Level 2 Event load event type can now be dispatched to more [HTML 4.01] elements. blur and focus have been clarified and restricted to [HTML 4.01] applications only.

B.1.3 Changes to DOM Level 2 Events interfaces

Interface Event: The Event interface has a new attribute Event.namespaceURI, and a four new methods: Event.isCustom(), Event.stopImmediatePropagation(), Event.isDefaultPrevented(), and Event.initEventNS.
Interface EventTarget: The EventTarget interface has four new methods: EventTarget.addEventListenerNS(namespaceURI, type, listener, useCapture, evtGroup), EventTarget.removeEventListenerNS(namespaceURI, type, listener, useCapture), EventTarget.willTriggerNS(namespaceURI, type), EventTarget.hasEventListenerNS(namespaceURI, type). The method EventTarget.dispatchEvent(evt) was modified.
Interface DocumentEvent: The DocumentEvent interface has one new method: DocumentEvent.canDispatch(namespaceURI, type).
Interface UIEvent: The UIEvent interface has a new method UIEvent.initUIEventNS(...).
Interface MouseEvent: The MouseEvent interface has two new methods MouseEvent.getModifierState(keyIdentifierArg) and MouseEvent.initMouseEventNS(...).
Interface MutationEvent: The MutationEvent interface has a new method MutationEvent.initMutationEventNS(...).
Exception EventException: The DISPATCH_REQUEST_ERR constant has been added.

B.1.4 New Interfaces

The interfaces CustomEvent, TextEvent, KeyboardEvent, and MutationNameEvent were added to the Events module.