Fex4中使用Group滑动翻页

<?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" 
               minWidth="955" minHeight="600">
    <fx:Script>
        <![CDATA[
        import spark.core.NavigationUnit;
 
        /**
         * 上一页
         */
        private function prePageHandler():void
        {
            smp.valueBy = hGroup.getHorizontalScrollPositionDelta(NavigationUnit.PAGE_LEFT);
            anmiate.play();
        }
 
        /**
         * 下一页
         */
        private function nextPageHandler():void
        {
            smp.valueBy = hGroup.getHorizontalScrollPositionDelta(NavigationUnit.PAGE_RIGHT);
            anmiate.play();
        }
 
        ]]>
    </fx:Script>
    <fx:Declarations>
        <s:Animate id="anmiate" target="{hGroup}" duration="800">
            <s:motionPaths>
                <s:SimpleMotionPath id="smp" property="horizontalScrollPosition"/>
            </s:motionPaths>
        </s:Animate>
    </fx:Declarations>
    <s:Panel title="Flex4 Group新特性">
        <s:HGroup id="hGroup" gap="10" height="100" width="320" clipAndEnableScrolling="true">
            <s:Button width="100" height="100" label="1" fontSize="30"/>
            <s:Button width="100" height="100" label="2" fontSize="30"/>
            <s:Button width="100" height="100" label="3" fontSize="30"/>
            <s:Button width="100" height="100" label="4" fontSize="30"/>
            <s:Button width="100" height="100" label="5" fontSize="30"/>
            <s:Button width="100" height="100" label="6" fontSize="30"/>
            <s:Button width="100" height="100" label="7" fontSize="30"/>
        </s:HGroup>
        <s:controlBarContent>
            <s:HGroup width="100%" horizontalAlign="center">
                <s:Button label="上一页" click="prePageHandler()"/>
                <s:Button label="下一页" click="nextPageHandler()"/>
            </s:HGroup>
        </s:controlBarContent>
    </s:Panel>
</s:Application>