Big refactoring to allow for multi-bindings from a single dispatcher.

v3/src/events/EventBinding.js

@@ -0,0 +1,233 @@
+var CONST = require('./const');
+var EventListener = require('./EventListener');
+
+var EventBinding = function (dispatcher, type)
+{
+    this.dispatcher = dispatcher;
+    this.type = type;
+    this.state = CONST.DISPATCHER_IDLE;
+    this.active = [];
+};
+
+EventBinding.prototype.constructor = EventBinding;
+
+EventBinding.prototype = {
+
+    get: function (callback)
+    {
+        for (var i = 0; i < this.active.length; i++)
+        {
+            if (this.active[i].callback === callback)
+            {
+                return this.active[i];
+            }
+        }
+    },
+
+    getIndex: function (callback)
+    {
+        for (var i = 0; i < this.active.length; i++)
+        {
+            if (this.active[i].callback === callback)
+            {
+                return i;
+            }
+        }
+
+        return null;
+    },
+
+    has: function (callback)
+    {
+        return (this.get(callback));
+    },
+
+    add: function (callback, priority, once)
+    {
+        var listener = this.get(callback);
+
+        if (!listener)
+        {
+            //  The listener doesn't exist, so create one
+            listener = EventListener(this.type, callback, priority, once);
+        }
+        else
+        {
+            //  Listener already exists, abort
+            return;
+        }
+
+        if (this.state === CONST.DISPATCHER_IDLE)
+        {
+            //  The Dispatcher isn't doing anything, so we don't need a pending state
+            listener.state = CONST.LISTENER_ACTIVE;
+        }
+
+        this.active.push(listener);
+
+        this.active.sort(this.sortHandler);
+    },
+
+    sortHandler: function (listenerA, listenerB)
+    {
+        if (listenerB.priority < listenerA.priority)
+        {
+            return -1;
+        }
+        else if (listenerB.priority > listenerA.priority)
+        {
+            return 1;
+        }
+        else
+        {
+            return 0;
+        }
+    },
+
+    remove: function (callback)
+    {
+        if (this.state === CONST.DISPATCHER_IDLE)
+        {
+            //  The Dispatcher isn't doing anything, so we can remove right away
+            var i = this.getIndex(callback);
+
+            if (i !== null)
+            {
+                this.active.splice(i, 1);
+            }
+        }
+        else if (this.state === CONST.DISPATCHER_DISPATCHING)
+        {
+            //  The Dispatcher is working, so we flag the listener for removal at the end
+            var listener = this.get(callback);
+
+            if (listener)
+            {
+                listener.state = CONST.LISTENER_REMOVING;
+            }
+        }
+    },
+
+    dispatch: function (event)
+    {
+        if (this.state !== CONST.DISPATCHER_IDLE)
+        {
+            throw new Error('Error: Failed to execute \'EventDispatcher.dispatch\' on \'' + this.type + '\': The event is already being dispatched.');
+        }
+        else if (this.active.length === 0)
+        {
+            //  This was a valid dispatch call, we just had nothing to do ...
+            return true;
+        }
+
+        this.state = CONST.DISPATCHER_DISPATCHING;
+
+        console.log('Dispatching', this.active.length, 'listeners');
+
+        var listener;
+
+        event.reset(this.dispatcher);
+
+        for (var i = 0; i < this.active.length; i++)
+        {
+            listener = this.active[i];
+
+            if (listener.state !== CONST.LISTENER_ACTIVE)
+            {
+                continue;
+            }
+
+            listener.callback.call(this.dispatcher, event);
+
+            //  Has the callback changed the state of this binding?
+            if (this.state !== CONST.DISPATCHER_DISPATCHING)
+            {
+                //  Yup! Let's break out
+                break;
+            }
+
+            //  Was it a 'once' listener?
+            if (listener.once)
+            {
+                listener.state = CONST.LISTENER_REMOVING;
+            }
+
+            //  Has the event been halted by the callback?
+            if (!event._propagate)
+            {
+                //  Break out, a listener has called Event.stopPropagation
+                break;
+            }
+        }
+
+        //  Dispatch over, or aborted
+        if (this.state === CONST.DISPATCHER_REMOVING)
+        {
+            this.removeAll();
+        }
+        else if (this.state === CONST.DISPATCHER_DESTROYED)
+        {
+            this.dispatcher.delete(this.type);
+        }
+        else
+        {
+            //  All done, just purge the list
+            this.tidy();
+
+            this.state = CONST.DISPATCHER_IDLE;
+        }
+    },
+
+    //  Removes all listeners
+    //  If this is currently being dispatched then don't remove 'pending' listeners
+    //  (i.e. ones that were added during the dispatch), only active ones
+    removeAll: function ()
+    {
+        if (this.state === CONST.DISPATCHER_IDLE)
+        {
+            this.active.length = 0;
+        }
+        else
+        {
+            var i = this.active.length;
+
+            while (i--)
+            {
+                if (this.active[i].state !== CONST.LISTENER_PENDING)
+                {
+                    this.active.slice(i, 1);
+                }
+            }
+
+            this.state = CONST.DISPATCHER_IDLE;
+        }
+    },
+
+    tidy: function ()
+    {
+        var i = this.active.length;
+
+        while (i--)
+        {
+            if (this.active[i].state === CONST.LISTENER_REMOVING)
+            {
+                this.active.slice(i, 1);
+            }
+            else if (this.active[i].state === CONST.LISTENER_PENDING)
+            {
+                this.active[i].state === CONST.LISTENER_ACTIVE;
+            }
+        }
+    },
+
+    destroy: function ()
+    {
+        this.active.length = 0;
+        this.dispatcher = undefined;
+        this.type = '';
+        this.state = CONST.DISPATCHER_DESTROYED;
+    }
+
+};
+
+module.exports = EventBinding;

v3/src/events/EventDispatcher.js

@@ -1,88 +1,42 @@
+var EventBinding = require('./EventBinding');
+
 var EventDispatcher = function ()
 {
-    this.listeners = {};
+    this.bindings = {};
-
-    this._state = EventDispatcher.STATE_PENDING;
 };
 
-EventDispatcher.STATE_PENDING = 0;
-EventDispatcher.STATE_DISPATCHING = 1;
-EventDispatcher.STATE_REMOVING_ALL = 2;
-EventDispatcher.STATE_DESTROYED = 3;
-
 EventDispatcher.prototype.constructor = EventDispatcher;
 
 EventDispatcher.prototype = {
 
-    //  Private
+    getBinding: function (type)
-    add: function (type, listener, priority, isOnce)
     {
-        if (this.listeners === undefined)
+        if (this.bindings.hasOwnProperty(type))
         {
-            //  Has the EventDispatcher been destroyed?
+            return this.bindings[type];
-            return;
-        }
-
-        // console.log('Add listener', type, listener);
-
-        if (!this.listeners[type])
-        {
-            this.listeners[type] = [];
-        }
-
-        var listeners = this.listeners[type];
-
-        if (this.has(type, listener))
-        {
-            this.update(type, listener, priority, isOnce);
-        }
-        else
-        {
-            listeners.push({ listener: listener, priority: priority, isOnce: isOnce, toRemove: false });
-        }
-
-        listeners.sort(this.sortHandler);
-    },
-
-    sortHandler: function (listenerA, listenerB)
-    {
-        if (listenerB.priority < listenerA.priority)
-        {
-            return -1;
-        }
-        else if (listenerB.priority > listenerA.priority)
-        {
-            return 1;
-        }
-        else
-        {
-            return 0;
         }
     },
 
-    update: function (type, listener, priority, isOnce)
+    createBinding: function (type)
     {
-        var listeners = this.listeners[type];
+        if (!this.getBinding(type))
-
-        for (var i = 0; i < listeners.length; i++)
         {
-            if (listeners[i].listener === listener)
+            this.bindings[type] = new EventBinding(this, type);
-            {
-                //  They're trying to add the same listener again, so just update the priority + once
-                listeners[i].priority = priority;
-                listeners[i].isOnce = isOnce;
-            }
         }
 
+        return this.bindings[type];
     },
 
-    //  Need to test what happens if array is sorted during DISPATCH phase (does it screw it all up?)
-
     on: function (type, listener, priority)
     {
         if (priority === undefined) { priority = 0; }
 
-        this.add(type, listener, priority, false);
+        var binding = this.createBinding(type);
+
+        if (binding)
+        {
+            binding.add(type, listener, priority, false);
+        }
 
         return this;
     },
@@ -91,69 +45,39 @@ EventDispatcher.prototype = {
     {
         if (priority === undefined) { priority = 0; }
 
-        this.add(type, listener, priority, true);
+        var binding = this.createBinding(type);
+
+        if (binding)
+        {
+            binding.add(type, listener, priority, true);
+        }
 
         return this;
     },
 
-    total: function (type)
-    {
-        if (!this.listeners || !this.listeners[type])
-        {
-            return -1;
-        }
-
-        return this.listeners[type].length;
-    },
-
     has: function (type, listener)
     {
-        if (!this.listeners || !this.listeners[type])
+        var binding = this.getBinding(type);
+
+        if (binding)
+        {
+            return binding.has(listener);
+        }
+        else
         {
             return false;
         }
-
-        var listeners = this.listeners[type];
-
-        for (var i = 0; i < listeners.length; i++)
-        {
-            if (listeners[i].listener === listener)
-            {
-                return true;
-            }
-        }
-
-        return false;
     },
 
     //  Removes an event listener.
     //  If there is no matching listener registered with the EventDispatcher, a call to this method has no effect.
     off: function (type, listener)
     {
-        if (!this.listeners || !this.listeners[type])
+        var binding = this.getBinding(type);
-        {
-            return this;
-        }
 
-        var listeners = this.listeners[type];
+        if (binding)
-
-        for (var i = 0; i < listeners.length; i++)
         {
-            if (listeners[i].listener === listener)
+            binding.remove(listener);
-            {
-                if (this._state === EventDispatcher.STATE_DISPATCHING)
-                {
-                    console.log('Flag listener for removal', type);
-                    listeners[i].toRemove = true;
-                }
-                else
-                {
-                    console.log('Remove listener', type);
-                    listeners.splice(i, 1);
-                }
-
-                break;
-            }
         }
 
         return this;
@@ -161,130 +85,71 @@ EventDispatcher.prototype = {
 
     dispatch: function (event)
     {
-        //  Add in a dispatch lock, to stop the dispatcher from being invoked during an event callback
+        var binding;
 
-        if (this._state !== EventDispatcher.STATE_PENDING || !this.listeners[event.type])
+        if (Array.isArray(event))
         {
-            return false;
+            for (var i = 0; i < event.length; i++)
-        }
-
-        var listeners = this.listeners[event.type];
-
-        //  This was a valid dispatch call, we just had nothing to do ...
-        if (listeners.length === 0)
             {
-            return true;
+                binding = this.getBinding(event[i].type);
-        }
 
-        this._state = EventDispatcher.STATE_DISPATCHING;
+                if (binding)
-
-        event.reset(this);
-
-        var toRemove = [];
-
-        var entry;
-        var entries = listeners.slice();
-        // var entries = listeners;
-
-        console.log('Dispatching', entries.length, 'listeners');
-
-        for (var i = 0; i < entries.length; i++)
                 {
-            entry = entries[i];
+                    return binding.dispatch(event[i]);
-
-            if (entry.toRemove)
-            {
-                toRemove.push(entry);
-                continue;
-            }
-
-            //  Add Custom Events
-            //  If this adjusts the entries.length for any reason, the reference is still valid
-            entry.listener.call(this, event);
-
-            //  Has the callback done something disastrous? Like called removeAll, or nuked the dispatcher?
-            if (this._state !== EventDispatcher.STATE_DISPATCHING)
-            {
-                //  Yup! Let's get out of here ...
-                break;
-            }
-
-            //  Was a 'once' or was removed during the callback
-            if (entry.isOnce || entry.toRemove)
-            {
-                toRemove.push(entry);
-            }
-
-            //  Has the event been halted?
-            if (!event._propagate)
-            {
-                //  Break out, a listener has called Event.stopPropagation
-                break;
                 }
             }
-
-        if (this._state === EventDispatcher.STATE_REMOVING_ALL)
-        {
-            this.removeAll();
-        }
-        else if (this._state === EventDispatcher.STATE_DESTROYED)
-        {
-            this.destroy();
         }
         else
         {
-            //  Anything in the toRemove list?
+            binding = this.getBinding(event.type);
 
-            console.log('Cleaning out', toRemove.length, 'listeners');
+            if (binding)
-
-            for (i = 0; i < toRemove.length; i++)
             {
-                this.off(event.type, toRemove[i].listener);
+                return binding.dispatch(event);
             }
-
-            toRemove.length = 0;
-
-            this._state = EventDispatcher.STATE_PENDING;
         }
-
-        return true;
     },
 
     //  Removes all listeners, but retains the event type entries
-    removeAll: function ()
+    removeAll: function (type)
     {
-        if (this._state === EventDispatcher.STATE_DISPATCHING)
+        var binding = this.getBinding(type);
-        {
-            this._state = EventDispatcher.STATE_REMOVING_ALL;
 
-            return;
+        if (binding)
-        }
-
-        for (var eventType in this.listeners)
         {
-            this.listeners[eventType].length = 0;
+            binding.removeAll();
         }
 
         return this;
     },
 
+    delete: function (type)
+    {
+        var binding = this.getBinding(type);
+
+        if (binding)
+        {
+            binding.destroy();
+
+            delete this.bindings[type];
+        }
+
+        return this;
+    },
+
+    deleteAll: function ()
+    {
+        for (var binding in this.bindings)
+        {
+            binding.destroy();
+        }
+
+        this.bindings = {};
+    },
+
     destroy: function ()
     {
-        if (this._state === EventDispatcher.STATE_DISPATCHING)
+        //  What would it do any differently to deleteAll?
-        {
-            this._state = EventDispatcher.STATE_DESTROYED;
-
-            return;
-        }
-
-        for (var eventType in this.listeners)
-        {
-            this.listeners[eventType].length = 0;
-
-            delete this.listeners[eventType];
-        }
-
-        this.listeners = undefined;
     }
 
 };

v3/src/events/EventListener.js

@@ -0,0 +1,14 @@
+var CONST = require('./const');
+
+var EventListener = function (type, callback, priority, once)
+{
+    return {
+        type: type,
+        callback: callback,
+        priority: priority,
+        once: once,
+        state: CONST.LISTENER_PENDING
+    };
+};
+
+module.exports = EventListener;

v3/src/events/const.js

@@ -0,0 +1,14 @@
+var EVENT_CONST = {
+
+    DISPATCHER_IDLE: 0,
+    DISPATCHER_DISPATCHING: 1,
+    DISPATCHER_REMOVING: 2,
+    DISPATCHER_DESTROYED: 3,
+
+    LISTENER_PENDING: 4,
+    LISTENER_ACTIVE: 5,
+    LISTENER_REMOVING: 6
+
+};
+
+module.exports = EVENT_CONST;