<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" xmlns:s="library://ns.adobe.com/flex/spark" xmlns:local="*" width="440" viewSourceURL="srcview/index.html"> <fx:Script> <![CDATA[ import mx.collections.ArrayList; private function createItems(n:int):ArrayList { var arr:Array = new Array(); for (var i:int = 0; i < n; i++){ arr.push(i); } return new ArrayList(arr); } ]]> </fx:Script> <s:layout> <s:VerticalLayout horizontalAlign="center" paddingTop="10" /> </s:layout> <s:Label text="useVirtualLayout = false, 20 items" fontWeight="bold" fontSize="16" /> <s:List id="notVirtual" itemRenderer="SimpleRenderer" width="400" height="116" useVirtualLayout="false" dataProvider="{createItems(20)}"> <s:layout> <local:SimpleHorizontalLayout /> </s:layout> </s:List> <s:Label text="useVirtualLayout = true, 1000 items" fontWeight="bold" fontSize="16" /> <s:List id="virtual" itemRenderer="SimpleRenderer" width="400" height="116" useVirtualLayout="true" dataProvider="{createItems(1000)}"> <s:layout> <local:SimpleHorizontalLayout /> </s:layout> </s:List> </s:Application>