Точный путь не помогает((.Подробный код .

Код AS3:
<?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">
<fx:Script>
<![CDATA[
var a:int=0;
protected function button1_clickHandler(event:MouseEvent):void
{
var treb1:Object= new Object();
treb1.df_id=L_ID.text;
treb1.df_name=L_Name.text;
treb1.df_mark=L_Mark.text;
if (spisokXML.ychenik[0] == null )
{
a=0;
}
else
{
a=spisokXML.children().length()-1
a=a+1;
}
spisokXML.appendChild(<ychenik ID=" "> </ychenik>);
spisokXML.ychenik[a].@ID=a;
spisokXML.ychenik[a].df_id=treb1.df_id;
spisokXML.ychenik[a].df_name=treb1.df_name;
spisokXML.ychenik[a].df_mark=treb1.df_mark;
DataG.dataProvider=spisokXML.ychenik;
a++
}
protected function button2_clickHandler(event:MouseEvent):void
{
// TODO Auto-generated method stub
var fr:FileReference = new FileReference();
fr.save( spisokXML, 'spisok.xml')
}
]]>
</fx:Script>
<fx:Declarations>
<!-- Разместить невизуальные элементы (например, службы или объекты значений) -->
<fx:XML id="spisokXML" xmlns="" format="e4x" source="spisok.xml" />
</fx:Declarations>
<mx:DataGrid id="DataG" x="91" y="191" width="515" height="207"
dataProvider="{spisokXML.ychenik}" editable="true">
<mx:columns>
<mx:DataGridColumn editable="true" dataField="df_id" headerText="Id" />
<mx:DataGridColumn editable="true" dataField="df_name" headerText="Name"/>
<mx:DataGridColumn editable="true" dataField="df_mark" headerText="Mark"/>
</mx:columns>
</mx:DataGrid>
<s:Button x="223" y="471" label="add" click="button1_clickHandler(event)"/>
<s:TextInput id="L_ID" x="165" y="42"/>
<s:TextInput id="L_Name" x="165" y="77"/>
<s:TextInput id="L_Mark" x="165" y="119"/>
<s:Button x="435" y="470" label="save" click="button2_clickHandler(event)"/>
</s:WindowedApplication>