如何反向播放效果

Question

在一个函数中，我调用效果的 play 方法，在另一个函数中，我调用反向方法。 play 方法有效，但反向方法无效。 propertyChangesArray 似乎用于存储先前的效果起始值，但在调用反向时该属性为 null。我该怎么做？

代码：

        private var targetEffect:SetAction = new SetAction();
        public var sequence:Sequence = new Sequence();

        protected function play_clickHandler(event:MouseEvent):void {
            targetEffect.target = sparkImage;
            targetEffect.property = "width";
            targetEffect.captureStartValues();
            targetEffect.value = 300;
            trace("properties change array " + targetEffect.mx_internal::propertyChangesArray); // [Object]

            if (sequence.children.length==0) {
                sequence.addChild(targetEffect);
            }


            sequence.captureStartValues();
            trace("properties change array " + sequence.mx_internal::propertyChangesArray); // [Object]
            sequence.play();
        }


        protected function reverse_clickHandler(event:MouseEvent):void {
            var o:Object = targetEffect.mx_internal::propertyChangesArray;
            trace("reverse properties change array " + o); // null
            o = sequence.mx_internal::propertyChangesArray;
            trace("reverse  " + o); // null
            targetEffect.reverse();
            sequence.reverse();
        }

Answer 1

调用reverse()后，需要调用play()：

targetEffect.reverse(  );
targetEffect.play(  );