图片遮罩

 

<mx:Canvas width="100%" height="100%" >
		<mx:Image source="../assets/Desert.jpg" x="10" y="10" mask="{maskCanvas}">
			<mx:filters>
				<filters:DropShadowFilter />
			</mx:filters>
		</mx:Image>
		<mx:Canvas x="81" y="62" width="344" height="274" backgroundColor="#ff0000" id="maskCanvas" cornerRadius="15" borderStyle="solid" />
	</mx:Canvas>

<?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"
					   xmlns:filters="flash.filters.*"
					   showStatusBar="false" backgroundAlpha="0"
					   >
	<fx:Declarations>
		<!-- 将非可视元素（例如服务、值对象）放在此处 -->
	</fx:Declarations>

	<mx:Image source="../assets/Desert.jpg" mask="{maskCanvas}" />
	
	<mx:Canvas width="100%" height="100%" id="maskCanvas" cornerRadius="9" borderStyle="solid" />
	
</s:WindowedApplication>