Files
openlayers/src/ol/observable.js
2014-01-15 14:49:16 +01:00

70 lines
2.1 KiB
JavaScript

goog.provide('ol.Observable');
goog.require('goog.events');
goog.require('goog.events.EventTarget');
/**
* An event target providing convenient methods for listener registration
* and unregistration.
* @constructor
* @extends {goog.events.EventTarget}
* @suppress {checkStructDictInheritance}
* @struct
* @todo stability experimental
*/
ol.Observable = function() {
goog.base(this);
};
goog.inherits(ol.Observable, goog.events.EventTarget);
/**
* Listen for a certain type of event.
* @param {string|Array.<string>} type The event type or array of event types.
* @param {function(?): ?} listener The listener function.
* @param {Object=} opt_this The object to use as `this` in `listener`.
* @return {goog.events.Key} Unique key for the listener.
* @todo stability experimental
*/
ol.Observable.prototype.on = function(type, listener, opt_this) {
return goog.events.listen(this, type, listener, false, opt_this);
};
/**
* Listen once for a certain type of event.
* @param {string|Array.<string>} type The event type or array of event types.
* @param {function(?): ?} listener The listener function.
* @param {Object=} opt_this The object to use as `this` in `listener`.
* @return {goog.events.Key} Unique key for the listener.
* @todo stability experimental
*/
ol.Observable.prototype.once = function(type, listener, opt_this) {
return goog.events.listenOnce(this, type, listener, false, opt_this);
};
/**
* Unlisten for a certain type of event.
* @param {string|Array.<string>} type The event type or array of event types.
* @param {function(?): ?} listener The listener function.
* @param {Object=} opt_this The object to use as `this` in `listener`.
* @todo stability experimental
*/
ol.Observable.prototype.un = function(type, listener, opt_this) {
goog.events.unlisten(this, type, listener, false, opt_this);
};
/**
* Removes an event listener using the key returned by `on()` or `once()`.
* @param {goog.events.Key} key Key.
* @todo stability experimental
*/
ol.Observable.prototype.unByKey = function(key) {
goog.events.unlistenByKey(key);
};