Flex 4中的List组件自动滚动
下面的例子中的scrollToIndex()方法向您展示了如何将滚动条滚动至特定的区域。
<?xml version="1.0" encoding="utf-8"?><!-- http://blog.flexexamples.com/2009/05/30/setting-the-vertical-scroll-position-on-a-spark-list-control-in-flex-4/ --><s:Application name="Spark_List_layout_VerticalLayout_verticalScrollPosition_test" xmlns:fx="http://ns.adobe.com/mxml/2009" xmlns:s="library://ns.adobe.com/flex/spark" xmlns:mx="library://ns.adobe.com/flex/mx"><s:controlBarContent><mx:Form styleName="plain"><mx:FormItem label="verticalScrollPosition:"><s:HSlider id="slider" /></mx:FormItem></mx:Form></s:controlBarContent><fx:Script><![CDATA[import mx.events.FlexEvent;protected function list_creationCompleteHandler(evt:FlexEvent):void {slider.maximum = list.dataGroup.contentHeight - list.height;}]]></fx:Script><s:List id="list"horizontalCenter="0"verticalCenter="0"creationComplete="list_creationCompleteHandler(event);"><s:layout><s:VerticalLayout horizontalAlign="justify" requestedRowCount="4" verticalScrollPosition="{slider.value}" /></s:layout><s:dataProvider><s:ArrayList><fx:String>The</fx:String><fx:String>Quick</fx:String><fx:String>Brown</fx:String><fx:String>Fox</fx:String><fx:String>Jumps</fx:String><fx:String>Over</fx:String><fx:String>The</fx:String><fx:String>Lazy</fx:String><fx:String>Dog</fx:String></s:ArrayList></s:dataProvider></s:List></s:Application>下面的这个是自动滚动到List内容最下方：
<?xml version="1.0" encoding="utf-8"?><!-- shlei.iteye.com --><s:Application name="Spark_List_layout_VerticalLayout_verticalScrollPosition_test" xmlns:fx="http://ns.adobe.com/mxml/2009" xmlns:s="library://ns.adobe.com/flex/spark" xmlns:mx="library://ns.adobe.com/flex/mx"><fx:Script><![CDATA[import flash.utils.clearTimeout;import flash.utils.setTimeout;import mx.collections.ArrayCollection;import mx.events.FlexEvent;[Bindable]private var ac:ArrayCollection=new ArrayCollection();private var i:int=0;[Bindable]private var j:int;protected function list_creationCompleteHandler(evt:FlexEvent):void {add();}private function add():void{var k:uint = setTimeout(add,1000);i++;ac.addItem(i);/** 最主要的是下面这句，延迟获取List组件的内容高度最大值，否则拿不到内容高度最大值 **/if(-5<one())callLater(one);if(20==i)clearTimeout(k);}private function one():int{return j=list.dataGroup.contentHeight - list.height;}]]></fx:Script><s:List id="list"horizontalCenter="0"verticalCenter="0"dataProvider="{ac}"creationComplete="list_creationCompleteHandler(event);"><s:layout><s:VerticalLayout horizontalAlign="justify" requestedRowCount="4" verticalScrollPosition="{j}" /></s:layout></s:List></s:Application>参考 http://blog.flexexamples.com/2007/11/08/scrolling-to-a-specific-index-in-a-flex-list-control/
by Peter Dehaan and others