Getting started with flex – Hello World (runs in application)

<?xml version="1.0" encoding="utf-8"?>
<s:WindowedApplication xmlns:fx="http://ns.adobe.com/mxml/2009" 
                       xmlns:s="library://ns.adobe.com/flex/spark" 
                       xmlns:mx="library://ns.adobe.com/flex/mx">

    <s:Label text="Hello World!" />

</s:WindowedApplication>

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Getting started with flex – Hello World (runs in application) - CodeDay