<s:DropDownList xmlns:fx="http://ns.adobe.com/mxml/2009" xmlns:mx="library://ns.adobe.com/flex/mx" xmlns:s="library://ns.adobe.com/flex/spark"
    prompt="Select One">
    
    <s:dataProvider>
    	<mx:ArrayCollection>
    		<fx:String>Very long item name to see how it will be displayed in the DropDownList</fx:String>
    		<fx:String>Short Item</fx:String>
    		<fx:String>Select One</fx:String>
		</mx:ArrayCollection>
	</s:dataProvider>
	
</s:DropDownList>