flex4.5 DataGrid控制某行不可编辑

网上关于flex4.5的DataGrid例子很少，自己做的时候也遇到了很多问题。

应用程序中的DataGrid：（要用自定义的itemEditor）

?

<s:DataGrid id="osinfoData" width="100%" height="100%" alternatingRowColors="[#eeffff,#ffffff]" editable="true" dataProvider="{infoproperties}">
	<s:columns>
		<s:ArrayList>
			<s:GridColumn  headerText="名称" dataField="name" editable="false"/>
			<s:GridColumn headerText="值" dataField="value" editable="true" itemEditor="com.control.itemeditor.DataGridEditItemEditor"/>
		</s:ArrayList>
	</s:columns>
</s:DataGrid>

infoproperties列表格式：(edit控制该行是否可编辑)

	var infoproperties:ArrayCollection=new ArrayCollection();
	infoproperties.addItem({name:"id",value:"1",edit:false});
	infoproperties.addItem({name:"名称",edit:true});
	infoproperties.addItem({name:"xml名称",edit:true});
	infoproperties.addItem({name:"注释",edit:true});
	infoproperties.addItem({name:"创建时间",value:"2012-10-12 08:00:00",edit:false});
	infoproperties.addItem({name:"创建人",value:"me",edit:false});
	infoproperties.addItem({name:"最后修改时间",edit:false});
	infoproperties.addItem({name:"最后修改人",edit:false});

自定义DataGridEditItemEditor.mxml

<?xml version="1.0" encoding="utf-8"?>
<s:GridItemEditor xmlns:fx=http://ns.adobe.com/mxml/2009 xmlns:s="library://ns.adobe.com/flex/spark" xmlns:mx="library://ns.adobe.com/flex/mx" clipAndEnableScrolling="true">
	<fx:Script>
		<![CDATA[
			public var newValue:String;
			override public function set data(value:Object):void{
				super.data=value;
				txt.text=data.value;
				txt.editable=data.edit;
			}
		]]>
	</fx:Script>
	<s:TextInput id="txt" alpha="1" width="100%" height="100%" change="super.value = txt.text" updateComplete="newValue=txt.text;"/> 
</s:GridItemEditor>

注意：txt.text，和txt.editable要在set data时设置，写在TextInput标签里，初始化的时候data是null，取不到其中的值