flex3 comboBox 变身可输入可过滤搜索下拉选项，实例代码片段

<fx:Script>
    <![CDATA[
      ...............
      private var enterpriseInfoRO:RemoteObject=ServiceLocator.getInstance().getRemoteObject("enterpriseInfo_RO_ID") as RemoteObject;
      private var reportRO:RemoteObject=ServiceLocator.getInstance().getRemoteObject("reportRO") as RemoteObject;


      [Bindable]
      private var enterprise_info:Array=[];
      [Bindable] 
      public var inputEStr:String;
      
      private var checkBox:CheckBox;
      [Event(name="onDocumentLoadedError", type="flash.events.ErrorEvent")]
      
      ............

      //加载企业信息
      public function loadEnterpriseInfo():void
      {
        enterpriseInfoRO.getEnterprisesListByTID(cityInfo_CB_ID.selectedItem.value);
        enterpriseInfoRO.addEventListener(ResultEvent.RESULT, enterpriseInfo_Handle);
      }

      public function enterpriseInfo_Handle(e:ResultEvent):void
      {
        enterpriseInfoRO.removeEventListener(ResultEvent.RESULT, enterpriseInfo_Handle);
        if (e.result != null)
        {
          /**********返回列表*************/
          var tempList:ArrayCollection=e.result as ArrayCollection;
          var arr:Array=tempList.toArray();
          enterprise_info=[];
          for (var a in arr)
          {
            enterprise_info.push({label: arr[a][1], value: arr[a][0]});
          }
          enterpriseInfo_CB_ID.selectedIndex=0;
          //flag=true;
          loadReport();
        }
      }

      //加载报表信息
      public function loadReport():void
      {
        currentState='state1';
        inputEStr=enterpriseInfo_CB_ID.text;
        if (enterpriseInfo_CB_ID.selectedItem != null)
        {

          reportRO.getReportInfo(enterpriseInfo_CB_ID.selectedItem.value, time_ID.getTime_flag(), time_ID.getDate());
          reportRO.addEventListener(ResultEvent.RESULT, reportInfo_Handle);
        }
      }
      
      protected function search_keyUpHandler(event:KeyboardEvent):void
      {
        if(event.keyCode.toString()=='32'||event.keyCode.toString()=='13'||event.keyCode.toString()=='8'){
          inputEStr=enterpriseInfo_CB_ID.text;
          enterpriseInfoRO.getEnterprisesListByValue(cityInfo_CB_ID.selectedItem.value,StringUtil.trim(inputEStr));
          enterpriseInfoRO.addEventListener(ResultEvent.RESULT,_result_enterprise_bySearch); 
        }
      }
      
      private  function _result_enterprise_bySearch(e:ResultEvent):void{
        enterpriseInfoRO.removeEventListener(ResultEvent.RESULT,_result_enterprise_bySearch);
        if(e.result != null){
          /**********返回列表*************/
          var tempList: ArrayCollection = e.result as ArrayCollection;
          var arr: Array = tempList.toArray();
          var index:int=0;
          enterprise_info=[]; 
          for(var a in arr)
          {
            enterprise_info.push({label:arr[a][0],value:int(arr[a][1])});
            index++
          }

          enterpriseInfo_CB_ID.text=inputEStr;
          enterpriseInfo_CB_ID.open();
        }
        
      }
      public function reportInfo_Handle(e:ResultEvent):void
      {
        reportRO.removeEventListener(ResultEvent.RESULT, reportInfo_Handle);
        report_group_id.removeAllElements();
        if (e.result != null)
        {
          /**********返回列表*************/
          var tempList:ArrayCollection=e.result as ArrayCollection;
          var arr:Array=tempList.toArray();
          for (var a in arr)
          {
            var vGroup:VGroup=new VGroup();
            
            var image:Image=new Image();
            image.source=(String(arr[a][3]) == "0" ? "assets/png/report.png" : "assets/png/report2.png");
            image.name=String(arr[a][2]);
            image.useHandCursor="false";
            image.buttonMode="true";
            image.mouseChildren="false";
            image.addEventListener(MouseEvent.CLICK, reportDetail);
            
            vGroup.addElement(image);
            
            var hGroup:HGroup=new HGroup();
            
            var label:Label=new Label();
            label.text="表" + arr[a][1];
            
            var cb:CheckBox=new CheckBox();
            cb.label="审核";
            cb.selected=(String(arr[a][3]) == "0" ? false : true);
            cb.id=String(arr[a][0])+"##"+String(arr[a][2]);
            cb.addEventListener(Event.CHANGE,cb_change);
            
            hGroup.addElement(label);
            hGroup.addElement(cb);
            vGroup.addElement(hGroup);
            report_group_id.addElement(vGroup);
            
          }
          enterpriseInfo_CB_ID.text=inputEStr;
        }
      }

    



    ]]>
  </fx:Script>



  <s:BorderContainer width="100%"
        ..............    
        <mx:FormItem label="企业:"
               indicatorGap="0">
          <mx:ComboBox id="enterpriseInfo_CB_ID"
                 dataProvider="{enterprise_info}"
                 selectedIndex="0"
                 editable="true"
                 minWidth="100"
                 change="loadReport()"
                 keyUp="search_keyUpHandler(event)"
                 width="200"/>
        </mx:FormItem>

        ..............
  </s:BorderContainer>