13.8.过滤和排序XMLListCollection

<nutrition>
<food>
<name>Avocado Dip</name>
<calories>110</calories>
<total-fat>11</total-fat>
<saturated-fat>3</saturated-fat>
<cholesterol>5</cholesterol>
<sodium>210</sodium>
<carb>2</carb>
<fiber>0</fiber>
<protein>1</protein>
</food>
</nutrition>

coll.filterFunction = lowCalFilter;
private function lowCalFilter(value:Object):Boolean {
if(Number(value.calories) < 200) {
return true;
}
return false;
}

var sort:Sort = new Sort();
sort.fields = [new SortField("calories", false,false, true)];
coll.sort = sort;
coll.refresh();

<mx:VBox xmlns:mx="http://www.adobe.com/2006/mxml" width="400"
height="300" creationComplete="xmlService.send()">
<mx:HTTPService url="assets/data.xml" resultFormat="xml"
id="xmlService" result="createXMLCollection(event)"/>
<mx:Script>
<![CDATA[
import mx.collections.SortField;
import mx.collections.Sort;
import mx.rpc.events.ResultEvent;
import mx.collections.XMLListCollection;
[Bindable]
private var coll:XMLListCollection;
private function
createXMLCollection(event:ResultEvent):void {
var list:XMLList = new XMLList(event.result);
coll = new XMLListCollection(list.food);
var sort:Sort = new Sort();
sort.fields = [new SortField("calories", false, false, true)];
coll.sort = sort;
coll.refresh();
}
private function applyFilter():void {
coll.filterFunction = lowCalFilter;
coll.refresh();
}
private function lowCalFilter(value:Object):Boolean {
if(Number(value.calories) < 200) {
return true;
}
return false;
}

]]>
</mx:Script>
<mx:DataGrid dataProvider="{coll}">
<mx:columns>
<mx:DataGridColumn dataField="calories"/>
<mx:DataGridColumn dataField="name"/>
</mx:columns>
</mx:DataGrid>
<mx:Button click="applyFilter()" label="filter"/>
</mx:VBox>

private function lowFatFilter(value:Object):Boolean {
if(value.calories(@fat) < Number(value.calories)/5) {
return true;
}
return false;
}