     {
         super();
     }
+    
+    //--------------------------------------------------------------------------
+    //
+    //  Variables
+    //
+    //--------------------------------------------------------------------------
+    
+    /**
+     *  @private
+     *  This flag indicates when a user has called preventDefault on the
+     *  KeyboardEvent dispatched when the back key is pressed.
+     */
+    private var backKeyEventPreventDefaulted:Boolean = false;
     
     //--------------------------------------------------------------------------
     //

    private function deviceKeyUpHandler(event:KeyboardEvent):void
    {
        var key:uint = event.keyCode;
        
        if (key == Keyboard.BACK && canCancelBackKeyBehavior)
            backKeyHandler();
    }
    

        
        // We want to prevent the default down behavior for back key if 
        // the navigator has a view to pop back to
        if (key == Keyboard.BACK)
        {
            backKeyEventPreventDefaulted = event.isDefaultPrevented();
            
            if (canCancelBackKeyBehavior)
                event.preventDefault();
        }
    }
    
    /**
