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

    <mx:Binding source="textInputSrc.text"
            destination="textInputDst.text" />

    <mx:Form>
        <mx:FormItem label="source:">
            <mx:TextInput id="textInputSrc" />
        </mx:FormItem>
        <mx:FormItem label="destination:">
            <mx:TextInput id="textInputDst"
                    width="{textInputSrc.width}" />
        </mx:FormItem>
    </mx:Form>

</mx:Application>