Animation - guard around destroy

- Allows sprites (and/or the animation) to be destroyed from within
  the onUpdate, onLoop, or onComplete events

Author: pnstickne

src/animation/Animation.js

@@ -192,17 +192,7 @@ Phaser.Animation.prototype = {
         this._timeNextFrame = this.game.time.time + this.delay;
 
         this._frameIndex = 0;
-
-        this.currentFrame = this._frameData.getFrame(this._frames[this._frameIndex]);
-
-        this._parent.setFrame(this.currentFrame);
-
-        //  TODO: Double check if required
-        if (this._parent.__tilePattern)
-        {
-            this._parent.__tilePattern = false;
-            this._parent.tilingTexture = false;
-        }
+        this.updateCurrentFrame(false);
 
         this._parent.events.onAnimationStart$dispatch(this._parent, this);
 
@@ -391,6 +381,7 @@ Phaser.Animation.prototype = {
             {
                 if (this.loop)
                 {
+                    // Update current state before event callback
                     this._frameIndex %= this._frames.length;
                     this.currentFrame = this._frameData.getFrame(this._frames[this._frameIndex]);
                     this.loopCount++;
@@ -403,29 +394,56 @@ Phaser.Animation.prototype = {
                 }
             }
 
-            this.currentFrame = this._frameData.getFrame(this._frames[this._frameIndex]);
+            return this.updateCurrentFrame(true);
 
-            if (this.currentFrame)
-            {
-                this._parent.setFrame(this.currentFrame);
+        }
 
-                if (this._parent.__tilePattern)
-                {
-                    this._parent.__tilePattern = false;
-                    this._parent.tilingTexture = false;
-                }
+        return false;
 
-                if (this.onUpdate)
-                {
-                    this.onUpdate.dispatch(this, this.currentFrame);
-                }
+    },
+
+    /**
+    * Changes the currentFrame per the _frameIndex, updates the display state,
+    * and triggers the update signal.
+    *
+    * Returns true if the current frame update was 'successful', false otherwise.
+    *
+    * @method Phaser.Animation#updateCurrentFrame
+    * @param {bool} signalUpdate - If true th onUpdate signal will be triggered.
+    * @private
+    */
+    updateCurrentFrame: function (signalUpdate) {
+
+        if (!this._frameData)
+        {
+            // The animation is already destroyed, probably from a callback
+            return false;
+        }
+
+        this.currentFrame = this._frameData.getFrame(this._frames[this._frameIndex]);
+
+        if (this.currentFrame)
+        {
+            this._parent.setFrame(this.currentFrame);
+
+            if (this._parent.__tilePattern)
+            {
+                this._parent.__tilePattern = false;
+                this._parent.tilingTexture = false;
             }
+        }
 
+        if (this.onUpdate && signalUpdate)
+        {
+            this.onUpdate.dispatch(this, this.currentFrame);
+            // False if the animation was destroyed from within a callback
+            return !!this._frameData;
+        }
+        else
+        {
             return true;
         }
 
-        return false;
-
     },
 
     /**
@@ -455,24 +473,7 @@ Phaser.Animation.prototype = {
         if (frame !== this._frameIndex)
         {
             this._frameIndex = frame;
-
-            this.currentFrame = this._frameData.getFrame(this._frames[this._frameIndex]);
-
-            if (this.currentFrame)
-            {
-                this._parent.setFrame(this.currentFrame);
-
-                if (this._parent.__tilePattern)
-                {
-                    this._parent.__tilePattern = false;
-                    this._parent.tilingTexture = false;
-                }
-            }
-
-            if (this.onUpdate)
-            {
-                this.onUpdate.dispatch(this, this.currentFrame);
-            }
+            this.updateCurrentFrame(true);
         }
 
     },
@@ -504,24 +505,7 @@ Phaser.Animation.prototype = {
         if (frame !== this._frameIndex)
         {
             this._frameIndex = frame;
-
-            this.currentFrame = this._frameData.getFrame(this._frames[this._frameIndex]);
-
-            if (this.currentFrame)
-            {
-                this._parent.setFrame(this.currentFrame);
-
-                if (this._parent.__tilePattern)
-                {
-                    this._parent.__tilePattern = false;
-                    this._parent.tilingTexture = false;
-                }
-            }
-
-            if (this.onUpdate)
-            {
-                this.onUpdate.dispatch(this, this.currentFrame);
-            }
+            this.updateCurrentFrame(true);
         }
 
     },
@@ -546,6 +530,12 @@ Phaser.Animation.prototype = {
     */
     destroy: function () {
 
+        if (!this._frameData)
+        {
+            // Already destroyed
+            return;
+        }
+
         this.game.onPause.remove(this.onPause, this);
         this.game.onResume.remove(this.onResume, this);