[BeDLiNt]

Можно так:

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" xmlns:custom="custom.*"
	layout="absolute">
<mx:Script>
<![CDATA[

	[Bindable]
	private var textData:String="text text text text text text text text text";
	
]]>
</mx:Script>
	<mx:Canvas width="150" height="500">
		<mx:VBox width="100%" height="100%">
			<mx:TextArea id="ta" text="{textData}" width="100%" wordWrap="true"
				verticalScrollPolicy="off" 
				change="ta.height=ta.textHeight+15" 
				creationComplete="ta.height=ta.textHeight+15"/>
			<mx:DataGrid width="100%">
				<mx:columns>
					<mx:DataGridColumn headerText="Column 1" dataField="col1"/>
					<mx:DataGridColumn headerText="Column 2" dataField="col2"/>
					<mx:DataGridColumn headerText="Column 3" dataField="col3"/>
				</mx:columns>
			</mx:DataGrid>
		</mx:VBox>
	</mx:Canvas>
</mx:Application>