Add SelectEvent to Select interaction

Fixes

src/ol/interaction/selectinteraction.js

@@ -3,6 +3,7 @@ goog.provide('ol.interaction.Select');
 goog.require('goog.array');
 goog.require('goog.asserts');
 goog.require('goog.events');
+goog.require('goog.events.Event');
 goog.require('goog.functions');
 goog.require('ol.CollectionEventType');
 goog.require('ol.Feature');
@@ -13,6 +14,51 @@ goog.require('ol.interaction.Interaction');
 goog.require('ol.style.Style');
 
 
+/**
+ * @enum {string}
+ */
+ol.SelectEventType = {
+  /**
+   * Triggered when feature(s) has been (de)selected.
+   * @event ol.SelectEvent#select
+   * @api
+   */
+  SELECT: 'select'
+};
+
+
+
+/**
+ * @classdesc
+ * Events emitted by {@link ol.interaction.Select} instances are instances of
+ * this type.
+ *
+ * @param {string} type The event type.
+ * @param {Array.<ol.Feature>} selected Selected features.
+ * @param {Array.<ol.Feature>} deselected Deselected features.
+ * @extends {goog.events.Event}
+ * @constructor
+ */
+ol.SelectEvent = function(type, selected, deselected) {
+  goog.base(this, type);
+
+  /**
+   * Selected features array.
+   * @type {Array.<ol.Feature>}
+   * @api
+   */
+  this.selected = selected;
+
+  /**
+   * Deselected features array.
+   * @type {Array.<ol.Feature>}
+   * @api
+   */
+  this.deselected = deselected;
+};
+goog.inherits(ol.SelectEvent, goog.events.Event);
+
+
 
 /**
  * @classdesc
@@ -140,6 +186,7 @@ ol.interaction.Select.handleEvent = function(mapBrowserEvent) {
   var features = this.featureOverlay_.getFeatures();
   var /** @type {Array.<ol.Feature>} */ deselected = [];
   var /** @type {Array.<ol.Feature>} */ selected = [];
+  var change = false;
   if (set) {
     // Replace the currently selected feature(s) with the feature(s) at the
     // pixel, or clear the selected feature(s) if there is no feature at
@@ -156,7 +203,9 @@ ol.interaction.Select.handleEvent = function(mapBrowserEvent) {
         features.item(0) == selected[0]) {
       // No change
     } else {
+      change = true;
       if (features.getLength() !== 0) {
+        deselected = Array.prototype.concat(features.getArray());
         features.clear();
       }
       if (this.multi_) {
@@ -189,6 +238,13 @@ ol.interaction.Select.handleEvent = function(mapBrowserEvent) {
       features.remove(deselected[i]);
     }
     features.extend(selected);
+    if (selected.length > 0 || deselected.length > 0) {
+      change = true;
+    }
+  }
+  if (change) {
+    this.dispatchEvent(
+        new ol.SelectEvent(ol.SelectEventType.SELECT, selected, deselected));
   }
   return ol.events.condition.pointerMove(mapBrowserEvent);
 };