<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="middle"
        backgroundColor="white"
        creationComplete="init();" viewSourceURL="srcview/index.html">

    <mx:Script>
        <![CDATA[
            import mx.controls.Alert;

            private function init():void {
                var userAgent:String = ExternalInterface.call("navigator.userAgent.toString");
                Alert.show(userAgent, "navigator.userAgent:");
            }
        ]]>
    </mx:Script>

    <mx:ApplicationControlBar dock="true">
        <mx:Button label="Display user agent"
                click="init();" />
    </mx:ApplicationControlBar>

</mx:Application>