<?xml version="1.0" encoding="utf-8"?>
<mx:WindowedApplication xmlns:mx="http://www.adobe.com/2006/mxml" creationComplete="initApp()">

  <mx:Script>
    <![CDATA[
      import mx.collections.ArrayCollection;
      private var directory:File = File.documentsDirectory;

      private function initApp():void {
          directory.addEventListener(Event.SELECT, directorySelected);
      }
    
      private   function onClick():void {
        try
        {
            directory.browseForDirectory("Select Directory");
        }
        catch (error:Error)
        {
            trace("Failed:", error.message)
        }

      }

      private function directorySelected(event:Event):void {
          directory = event.target as File;
          var files:Array = directory.getDirectoryListing();
          var filenames:ArrayCollection = new ArrayCollection();

          for (var i:uint = 0; i < files.length; i++) {
            filenames.addItem(files[i].name);
          }
          fileList.dataProvider = filenames;
      }  
    ]]>
  </mx:Script>

  <mx:Button label="open" click="onClick()"/>
  <mx:List id="fileList" width="100%" height="100%"/>
    
</mx:WindowedApplication>