flex 13 RichTextEditor Test

RichTextEditor.mxml
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
 <mx:RichTextEditor title="Title" horizontalCenter="0" verticalCenter="0" id="rte">
 </mx:RichTextEditor>
 <mx:Button label="go" width="39" horizontalCenter="136" verticalCenter="128" click="show()"/>
 <mx:Script>
  <![CDATA[
   import mx.controls.Alert;
   function show():void{
    mx.controls.Alert.show(rte.htmlText);
   }
  ]]>
 </mx:Script>
</mx:Application>