OpenLayers 3 API Documentation

Class: Observable

ol.Observable

Abstract base class. An event target providing convenient methods for listener registration and unregistration. A generic change event is always available through ol.Observable#dispatchChangeEvent.

new ol.Observable() experimental

src/ol/observable.js, line 22

Subclasses

Extends

  • goog.events.EventTarget

Methods

dispatchChangeEvent() experimental

src/ol/observable.js, line 41

Dispatches a change event.

Fires:
  • change experimental

on(type, listener, opt_this){goog.events.Key} experimental

src/ol/observable.js, line 63

Listen for a certain type of event.

Name Type Description
type string | Array.<string>

The event type or array of event types.
listener function

The listener function.
this Object optional

The object to use as this in listener.
Returns:
Unique key for the listener.

once(type, listener, opt_this){goog.events.Key} experimental

src/ol/observable.js, line 76

Listen once for a certain type of event.

Name Type Description
type string | Array.<string>

The event type or array of event types.
listener function

The listener function.
this Object optional

The object to use as this in listener.
Returns:
Unique key for the listener.

un(type, listener, opt_this) experimental

src/ol/observable.js, line 88

Unlisten for a certain type of event.

Name Type Description
type string | Array.<string>

The event type or array of event types.
listener function

The listener function.
this Object optional

The object to use as this in listener.

unByKey(key) experimental

src/ol/observable.js, line 98

Removes an event listener using the key returned by on() or once().

Name Type Description
key goog.events.Key

Key.