Flex中对表格中某列的值进行数字格式化

1、问题背景

? ? ?一般的，表格中展示的比率，对比率的处理是：保留两位小数，并向上保留

2、实现实例

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" 
			   xmlns:s="library://ns.adobe.com/flex/spark" 
			   xmlns:mx="library://ns.adobe.com/flex/mx"
			   width="100%" height="100%" fontSize="12"
			   fontFamily="微软雅黑">
	<s:layout>
		<s:BasicLayout/>
	</s:layout>
	<fx:Script>
		<![CDATA[
			import mx.collections.ArrayCollection;
			import mx.events.FlexEvent;

			[Bindable]
			//表格数据绑定
			private var gridArray:ArrayCollection = new ArrayCollection([
				{week:"星期一",apple:"3676",rate:"0.7868"},{week:"星期二",apple:"4534",rate:"0.65454"},{week:"星期三",apple:"6758",rate:"0.876454"},{week:"星期四",apple:"9808",rate:"0.34224"},{week:"星期五",apple:"6567",rate:"0.9876523"},{week:"星期六",apple:"9000",rate:"0.566777"},{week:"星期日",apple:"4533",rate:"0.988787"}
			]);
			
			/**
			 * 对表格中的比率进行格式化
			 */
			private function formatDataGrid(item:Object,column:DataGridColumn):String
			{
				var temp:Number = item.rate;
				var data:String = dataFormatter.format(temp);
				return data;
			}
			
		]]>
	</fx:Script>
	<fx:Declarations>
		<!--格式化数字-->
		<mx:NumberFormatter id="dataFormatter" precision="2" rounding="up"/>
	</fx:Declarations>
	
	<mx:VBox width="100%" height="100%" paddingBottom="10" paddingLeft="10" paddingRight="20"
			 paddingTop="10" horizontalAlign="center">
		<mx:DataGrid id="dataGrid" width="100%" height="90%" dataProvider="{gridArray}" textAlign="center">
			<mx:columns>
				<mx:DataGridColumn headerText="星期" dataField="week"/>
				<mx:DataGridColumn headerText="苹果" dataField="apple"/>
				<mx:DataGridColumn headerText="比率" dataField="rate" labelFunction="formatDataGrid"/>
			</mx:columns>
		</mx:DataGrid>
		
	</mx:VBox>
</s:Application>