tools/dom/templates/html/impl/impl_EventTarget.darttemplate

// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

part of html;

/**
 * Base class that supports listening for and dispatching browser events.
 *
 * Events can either be accessed by string name (using the indexed getter) or by
 * getters exposed by subclasses. Use the getters exposed by subclasses when
 * possible for better compile-time type checks.
 * 
 * Using an indexed getter:
 *     events['mouseover'].add((e) => print("Mouse over!"));
 *
 * Using a getter provided by a subclass:
 *     elementEvents.mouseOver.add((e) => print("Mouse over!"));
 */
class Events {
  /* Raw event target. */
  final EventTarget _ptr;

  Events(this._ptr);

  EventListenerList operator [](String type) {
    return new EventListenerList(_ptr, type);
  }
}

/**
 * Supports adding, removing, and dispatching events for a specific event type.
 */
class EventListenerList {

  final EventTarget _ptr;
  final String _type;

  EventListenerList(this._ptr, this._type);

  // TODO(jacobr): implement equals.

  EventListenerList add(EventListener listener,
      [bool useCapture = false]) {
    _add(listener, useCapture);
    return this;
  }

  EventListenerList remove(EventListener listener,
      [bool useCapture = false]) {
    _remove(listener, useCapture);
    return this;
  }

  bool dispatch(Event evt) {
    return _ptr.$dom_dispatchEvent(evt);
  }

  void _add(EventListener listener, bool useCapture) {
    _ptr.$dom_addEventListener(_type, listener, useCapture);
  }

  void _remove(EventListener listener, bool useCapture) {
    _ptr.$dom_removeEventListener(_type, listener, useCapture);
  }
}
$ANNOTATIONS
/**
 * Base class for all browser objects that support events.
 *
 * Use the [on] property to add, remove, and dispatch events (rather than
 * [$dom_addEventListener], [$dom_dispatchEvent], and
 * [$dom_removeEventListener]) for compile-time type checks and a more concise
 * API.
 */ 
class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {

  @DomName('EventTarget.addEventListener, EventTarget.removeEventListener, EventTarget.dispatchEvent')
  Events get on => new Events(this);
$!MEMBERS
}