<?xml version="1.0" encoding="utf-8"?>
<mx:Application 
    xmlns="*"
    xmlns:mx="http://www.adobe.com/2006/mxml" 
    creationComplete="init();" viewSourceURL="srcview/index.html" >
    
    <mx:Script>
        <![CDATA[
            private function init():void {
                var array:Array = new Array();
                var array2:Array = new Array();
                
                for(var i:int=1; i<20; i++) {
                    array.push("Item " + i);
                    array2.push("Item " + (i + 20));            
                }
                
                list.dataProvider = array;
                list2.dataProvider = array2;
            }
        ]]>
    </mx:Script>
    
    <mx:HBox width="300" height="300">
        
        <DragSelectList id="list" 
            dragEnabled="true" dropEnabled="true" dragMoveEnabled="true"
            allowMultipleSelection="true"
             width="50%" height="100%" 
             itemRenderer="CheckBoxItemRenderer"
              />
         
        <DragSelectList id="list2" 
            dragEnabled="true" dropEnabled="true" dragMoveEnabled="true"
            allowMultipleSelection="true"
             width="50%" height="100%" 
             itemRenderer="CheckBoxItemRenderer"
              />
              
    </mx:HBox>
         
</mx:Application>