OpenLayers 3 API Documentation

Class: Observable

ol. Observable

experimental new ol.Observable()

src/ol/observable.js, line 19

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

Fires:
  • change

Subclasses

Extends

  • goog.events.EventTarget

Methods

experimental dispatchChangeEvent()

src/ol/observable.js, line 39

Dispatches a change event. Register a listener for this event to get notified of changes.

Fires:
  • change

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

src/ol/observable.js, line 61

Listen for a certain type of event.

Name Type Argument Description
type string | Array.<string>

The event type or array of event types.
listener function

The listener function.
this Object <optional>
 optional

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

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

src/ol/observable.js, line 74

Listen once for a certain type of event.

Name Type Argument Description
type string | Array.<string>

The event type or array of event types.
listener function

The listener function.
this Object <optional>
 optional

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

experimental un(type, listener, opt_this)

src/ol/observable.js, line 86

Unlisten for a certain type of event.

Name Type Argument Description
type string | Array.<string>

The event type or array of event types.
listener function

The listener function.
this Object <optional>
 optional

The object to use as this in listener.

experimental unByKey(key)

src/ol/observable.js, line 96

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

Name Type Description
key goog.events.Key

Key.