<?xml version="1.0" encoding="utf-8"?>

<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"

               xmlns:s="library://ns.adobe.com/flex/spark"

               xmlns:mx="library://ns.adobe.com/flex/mx"

               applicationComplete="onApplicationComplete(event)">

    <fx:Script>

        <![CDATA[

            import mx.events.FlexEvent;

            protected function onApplicationComplete(event:FlexEvent):void{

                // 统一进行事件的注册；

                circle.addEventListener(MouseEvent.MOUSE_DOWN,dragOn);

                circle.addEventListener(MouseEvent.MOUSE_UP,dragOff);

            }

            protected function dragOn(event:MouseEvent):void{

                // 这样就可以实现circle跟随鼠标拖动；

                circle.startDrag();

            }

            protected function dragOff(event:MouseEvent):void{

                // 这样就停止了circle的跟随鼠标拖动；

                circle.stopDrag();

            }

        ]]>

    </fx:Script>

    <fx:Declarations>

        <!-- 将非可视元素（例如服务、值对象）放在此处 -->

    </fx:Declarations>

    <s:Group id="circle">

        <s:Ellipse width="100" height="100">

            <s:fill>

                <s:SolidColor color="#009900"/>

            </s:fill>

            <s:stroke>

                <s:SolidColorStroke color="#000000" weight="2" />

            </s:stroke>

        </s:Ellipse>

    </s:Group>

</s:Application>