sprite: fix memory leak

Author: andrewrk

lib/sprite.js

@@ -18,6 +18,7 @@ function Sprite(animationName, params) {
   this.rotation    = params.rotation == null ? 0 : params.rotation;
   this.alpha       = params.alpha == null ? 1 : params.alpha;
 
+  setUpListeners(this);
   this.setAnimationName(animationName);
   this.setLoop(params.loop);
   this.setVisible(params.visible == null ? true : params.visible);
@@ -177,12 +178,16 @@ Sprite.prototype.getFrameIndex = function(){
 };
 
 Sprite.prototype['delete'] = function(){
+  if (this.interval) this.interval();
+  this.removeAllListeners();
   if (this.batch) this.batch.remove(this);
   this.batch = null;
 };
 
 function setUpInterval(self) {
-  if (self.interval) self.interval.cancel();
+  if (self.interval) self.interval();
+  self.interval = null;
+  if (self.animationEndListenCount === 0) return;
   var _schedule = self._loop ? schedule : wait;
   var now = new Date();
   var timeSinceStart = (now - self.animationStartDate) / 1000;
@@ -194,24 +199,29 @@ function setUpInterval(self) {
 
 function wait(sec, cb) {
   var interval = setTimeout(cb, sec * 1000);
-  return {
-    cancel: function(){
-      if (interval != null) {
-        clearTimeout(interval);
-        interval = null;
-      }
-    }
+  return function(){
+    clearTimeout(interval);
   };
 }
 
 function schedule(sec, cb) {
   var interval = setInterval(cb, sec * 1000);
-  return {
-    cancel: function(){
-      if (interval != null) {
-        clearInterval(interval);
-        interval = null;
-      }
-    }
+  return function(){
+    clearInterval(interval);
   };
 }
+
+function setUpListeners(self) {
+  self.on('newListener', function(event) {
+    if (event === 'animationend') {
+      self.animationEndListenCount += 1;
+      setUpInterval(self);
+    }
+  });
+  self.on('removeListener', function(event) {
+    if (event === 'animationend') {
+      self.animationEndListenCount -= 1;
+      setUpInterval(self);
+    }
+  });
+}