Merge pull request #2794 from elemoine/unbykey

Add ol.Observable.unByKey

src/ol/observable.js

@@ -34,6 +34,16 @@ ol.Observable = function() {
 goog.inherits(ol.Observable, goog.events.EventTarget);
 
 
+/**
+ * Removes an event listener using the key returned by `on()` or `once()`.
+ * @param {goog.events.Key} key The key returned by `on()` or `once()`.
+ * @api stable
+ */
+ol.Observable.unByKey = function(key) {
+  goog.events.unlistenByKey(key);
+};
+
+
 /**
  * Increases the revision counter and disptches a 'change' event.
  * @fires change
@@ -95,9 +105,10 @@ ol.Observable.prototype.un = function(type, listener, opt_this) {
 
 /**
  * Removes an event listener using the key returned by `on()` or `once()`.
- * @param {goog.events.Key} key Key.
+ * Note that using the {@link ol.Observable.unByKey} static function is to
+ * be preferred.
+ * @param {goog.events.Key} key The key returned by `on()` or `once()`.
+ * @function
  * @api stable
  */
-ol.Observable.prototype.unByKey = function(key) {
-  goog.events.unlistenByKey(key);
-};
+ol.Observable.prototype.unByKey = ol.Observable.unByKey;