flex mx_internal_uid的在数据传递时重复的解决方法

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml">
?<mx:Script>
??<![CDATA[
???import mx.utils.UIDUtil;
???import mx.collections.ArrayCollection;
???import mx.utils.ObjectUtil;
???
???[Bindable]
???public var dataArr:Array = [{label:"Red",data:"#FF0000"},
????{label:"Green",data:"#00FF00"},
????{label:"Blue",data:"#0000FF"}
???];
???[Bindable]
???public var problemArr:Array = new Array();
???
???private function addFromTopDG():void {
????problemArr.push(fromDG.selectedItem);
????//problemArr.push(ObjectUtil.copy(fromDG.selectedItem));
????toDG.dataProvider = problemArr;
???}
???
???private function addFromTopDG2():void {
????var obj:Object = ObjectUtil.copy(fromDG.selectedItem);
????obj.mx_internal_uid = UIDUtil.createUID();
????//这里千万不要直接fromDG.selectedItem.mx_internal_uid = UIDUtil.createUID();
????//因为上面说过这样引用关系还存在。
????(toDG.dataProvider as ArrayCollection).addItem(obj);
????obj = null;//这个就靠自己的CODE 风格啦，不要也没关系
???}
??]]>
?</mx:Script>
?<mx:DataGrid id="fromDG" width="600" height="200" dataProvider="{dataArr}">
??<mx:columns>
???<mx:Array>
????<mx:DataGridColumn width="300" dataField="mx_internal_uid"/>
????<mx:DataGridColumn dataField="label"/>
????<mx:DataGridColumn dataField="data"/>
???</mx:Array>
??</mx:columns>
?</mx:DataGrid>
?<mx:Button label="Add from Top_DG" click="addFromTopDG()"/>
?<mx:DataGrid id="toDG" width="600" height="200" dataProvider="{problemArr}">
??<mx:columns>
???<mx:Array>
????<mx:DataGridColumn width="300" dataField="mx_internal_uid"/>
????<mx:DataGridColumn dataField="label"/>
????<mx:DataGridColumn dataField="data"/>
???</mx:Array>
??</mx:columns>
?</mx:DataGrid>
</mx:Application>

来源：

http://www.voidcn.com/article/p-relvxpxg-bra.html