Filtering an XMLListCollection using Regular Expressions

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2009/04/01/filtering-an-xmllistcollection-using-regular-expressions/ -->
<s:Application name="XMLListCollection_filterFunction_RegExp_test"
        xmlns:fx="http://ns.adobe.com/mxml/2009"
        xmlns:s="library://ns.adobe.com/flex/spark"
        xmlns:mx="library://ns.adobe.com/flex/mx"
        backgroundColor="white">
    <s:layout>
        <s:VerticalLayout horizontalAlign="center" verticalAlign="middle" />
    </s:layout>
 
    <fx:Script>
        <![CDATA[
            private function textInput_change():void {
                if (textInput.text.length == 0) {
                    xmlListColl.filterFunction = null;
                } else {
                    xmlListColl.filterFunction = xmlListColl_filterFunc;
                }
                xmlListColl.refresh();
            }
 
            private function xmlListColl_filterFunc(item:Object):Boolean {
                if (textInput.text.length == 0) return true;
                var f:String = "ig";
                var wasRegExp:RegExp = new RegExp(textInput.text, f);
                var nowRegExp:RegExp = new RegExp(textInput.text, f);
                var wasMatch:Boolean = wasRegExp.test(item.@was);
                var nowMatch:Boolean = nowRegExp.test(item.@now);
 
                return (wasMatch || nowMatch);
            }
        ]]>
    </fx:Script>
 
    <fx:Declarations>
        <fx:XML id="nodesXML" source="nodes.xml" />
        <mx:XMLListCollection id="xmlListColl"
                source="{nodesXML.node}"
                filterFunction="xmlListColl_filterFunc" />
    </fx:Declarations>
 
    <s:controlBarContent>
        <mx:Form styleName="plain">
            <mx:FormItem label="Filter:">
                <s:TextInput id="textInput"
                        change="textInput_change();" />
            </mx:FormItem>
        </mx:Form>
    </s:controlBarContent>
 
    <mx:DataGrid id="dataGrid"
            dataProvider="{xmlListColl}"
            verticalScrollPolicy="on"
            width="90%"
            rowCount="10">
        <mx:columns>
            <mx:DataGridColumn dataField="@was" headerText="Was:" />
            <mx:DataGridColumn dataField="@now" headerText="Now:" />
        </mx:columns>
    </mx:DataGrid>
 
</s:Application>