Ans:

I think this is pretty good example for you. Please check this.

Itemrenderer.mxml

<?xml version="1.0" encoding="utf-8"?>
<s:ItemRenderer xmlns:fx="http://ns.adobe.com/mxml/2009" 
    xmlns:mx="library://ns.adobe.com/flex/mx" 
    xmlns:s="library://ns.adobe.com/flex/spark"
    autoDrawBackground="false">

    <fx:Script>
        <![CDATA[

            [Bindable]
            public var myBGColor:int = 0xFFFFFF;

            override public function set itemIndex(value:int):void { 
                if ((value%2) == 0) {
                    myBGColor= 0xFFFFFF;
                }
                if ((value%2) == 1) {
                    myBGColor= 0xCCFF66;
                }
            }
        ]]>
    </fx:Script>

    <s:states> 
        <s:State name="normal"/> 
        <s:State name="hovered"/> 
    </s:states> 

    <s:Rect id="myRect" 
        left="0" right="0" top="0" bottom="0" 
        alpha="1.0"> 
        <s:stroke> 
            <s:SolidColorStroke 
                color="0xA8C6EE" 
                weight="1"/> 
        </s:stroke> 
        <s:fill> 
            <s:SolidColor
                color="{myBGColor}"/> 
        </s:fill> 
    </s:Rect>     

    <s:Label id="labelDisplay" 
        verticalCenter="0" 
        left="3" right="3" top="6" bottom="4" 
        fontSize.hovered='14' fontStyle.hovered="italic"/> 
</s:ItemRenderer>

main.mxml

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" 
    xmlns:mx="library://ns.adobe.com/flex/mx" 
    xmlns:s="library://ns.adobe.com/flex/spark">

    <s:SkinnableDataContainer 
        itemRenderer="myComponents.MyAlternatingItemRenderer"> 
        <s:layout>
            <s:VerticalLayout/>
        </s:layout>
        <mx:ArrayList>
            <fx:String>Bill Smith</fx:String>
            <fx:String>Dave Jones</fx:String>
            <fx:String>Mary Davis</fx:String>
            <fx:String>Debbie Cooper</fx:String>
        </mx:ArrayList> 
    </s:SkinnableDataContainer> 
</s:Application>