Added optional scope to all event bindings

Author: photonstorm

v3/src/events/EventBinding.js

@@ -58,14 +58,16 @@ var EventBinding = new Class({
         return (this.get(callback));
     },
 
-    add: function (callback, priority, once)
+    //  Called by EventDispatcher.on and EventDispatcher.once
+    add: function (callback, priority, scope, once)
     {
+        //  EventListener
         var listener = this.get(callback);
 
         if (!listener)
         {
             //  The listener doesn't exist, so create one
-            listener = EventListener(this.type, callback, priority, once);
+            listener = EventListener(this.type, callback, scope, priority, once);
         }
         else
         {
@@ -148,14 +150,16 @@ var EventBinding = new Class({
 
         for (var i = 0; i < this.active.length; i++)
         {
+            //  EventListener
             listener = this.active[i];
 
             if (listener.state !== CONST.LISTENER_ACTIVE)
             {
                 continue;
             }
 
-            listener.callback.call(this.dispatcher, event);
+            // listener.callback.call(this.dispatcher, event);
+            listener.callback.call(listener.scope, event);
 
             //  Has the callback changed the state of this binding?
             if (this.state !== CONST.DISPATCHER_DISPATCHING)

v3/src/events/EventDispatcher.js

@@ -31,29 +31,31 @@ var EventDispatcher = new Class({
         return this.bindings[type];
     },
 
-    on: function (type, listener, priority)
+    on: function (type, listener, priority, scope)
     {
         if (priority === undefined) { priority = 0; }
+        if (scope === undefined) { scope = this; }
 
         var binding = this.createBinding(type);
 
         if (binding)
         {
-            binding.add(listener, priority, false);
+            binding.add(listener, priority, scope, false);
         }
 
         return this;
     },
 
-    once: function (type, listener, priority)
+    once: function (type, listener, priority, scope)
     {
         if (priority === undefined) { priority = 0; }
+        if (scope === undefined) { scope = this; }
 
         var binding = this.createBinding(type);
 
         if (binding)
         {
-            binding.add(listener, priority, true);
+            binding.add(listener, priority, scope, true);
         }
 
         return this;

v3/src/events/EventListener.js

@@ -1,10 +1,11 @@
 var CONST = require('./const');
 
-var EventListener = function (type, callback, priority, once)
+var EventListener = function (type, callback, scope, priority, once)
 {
     return {
         type: type,
         callback: callback,
+        scope: scope,
         priority: priority,
         once: once,
         state: CONST.LISTENER_PENDING