<?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" xmlns:component="component.*"
     >
 <fx:Script>
  <![CDATA[
   import mx.collections.ArrayCollection;
   [Bindable]
   public var acList:ArrayCollection = new ArrayCollection([
    {label:"JAVA",selected:false},
    {label:".NET",selected:false},
    {label:"C++",selected:false},
    {label:"FLEX",selected:false}]);
   public function getSelectionLabel():void{
      lbSelections.text = "";
      ddlMultiSelection.labelDisplay.text = "MultiSelected";
      for (var i:int = 0; i < acList.length; i++)
     {
         if(acList[i].selected){
            lbSelections.text += " " + acList[i].label;
          }
      }
   }
  ]]>
 </fx:Script>
 <s:HGroup width="100%" height="100" left="20" top="20" verticalAlign="middle">
      <s:DropDownList id="ddlMultiSelection"
              itemRenderer="renderers.MultiSelectItemRenderer"
              dataProvider="{acList}" close="getSelectionLabel()" />
       <s:Label id="lbSelections" text="Selected Items...."/>
 </s:HGroup>
</s:Application>

<?xml version="1.0" encoding="utf-8"?>
<s:ItemRenderer xmlns:fx="http://ns.adobe.com/mxml/2009"
    xmlns:s="library://ns.adobe.com/flex/spark"
    xmlns:mx="library://ns.adobe.com/flex/mx"
    autoDrawBackground="true" width="100%">
 <fx:Script>
  <![CDATA[
   import mx.core.IFlexDisplayObject;
   private function evnetMouseEventControll(event:MouseEvent):void{
       event.stopImmediatePropagation();
   }
   private function eventChangeSelection():void{
       data.selected = checkbox.selected;
   }
  ]]>
 </fx:Script>
 <s:CheckBox id="checkbox"
    width="100%"
    selected="{data.selected}"
    label="{data.label}"
    mouseUp="evnetMouseEventControll(event)"
    mouseDown="evnetMouseEventControll(event)"
    change="eventChangeSelection()"/>
 
</s:ItemRenderer>