Flex中如何创建自定义排序DataGrid控件的例子

接下来的例子演示了如何利用SortField类以及自定义的比较函数，来创建可以自定义排序的DataGrid控件。

让我们先来看一下Demo（

可以右键View Source或点击这里察看源代码

）：

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下面是完整代码(或点击这里察看)：



Download: main.mxml
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
<mx:Script>
<![CDATA[
import mx.collections.SortField;
import mx.collections.Sort;
import mx.controls.dataGridClasses.DataGridColumn;
import mx.utils.ObjectUtil;

private function sortOld():void {
var sortField:SortField = new SortField();
sortField.compareFunction = test2_compareFunc;
sortField.descending = checkBox.selected;

var oldSort:Sort = new Sort();
oldSort.fields = [sortField];

xmlListColl.sort = oldSort;
xmlListColl.refresh();
}

private function sortNew():void {
var sortField:SortField = new SortField();
sortField.compareFunction = test3_compareFunc;
sortField.descending = checkBox.selected;

var sort:Sort = new Sort();
sort.fields = [sortField];

xmlListColl.sort = sort;
xmlListColl.refresh();
}

private function resetSort():void {
xmlListColl.sort = null;
xmlListColl.refresh();
}

private function dataGridCol_labelFunc(item:XML, col:DataGridColumn):String {
return item.*.(@name == col.dataField).text();
}

private function test2_compareFunc(itemA:XML, itemB:XML):int {
var valueA:String = itemA.test2.text();
var valueB:String = itemB.test2.text();
return ObjectUtil.stringCompare(valueA, valueB);
}

private function test3_compareFunc(itemA:XML, itemB:XML):int {
var valueA:String = itemA.test3.text();
var valueB:String = itemB.test3.text();
return ObjectUtil.stringCompare(valueA, valueB);
}
]]>
</mx:Script>

<mx:XML id="tests" source="tests.xml" />
<mx:XMLListCollection id="xmlListColl" source="{tests.test}" />

<mx:ApplicationControlBar dock="true">
<mx:CheckBox id="checkBox" label="descending:" labelPlacement="left" />

<mx:Button label="Sort 'old'"
click="sortOld();" />
<mx:Button label="Sort 'new'"
click="sortNew();" />
<mx:Button label="Reset sort"
click="resetSort();" />
</mx:ApplicationControlBar>

<mx:DataGrid id="dataGrid"
dataProvider="{xmlListColl}"
width="300"
verticalScrollPolicy="on"
sortableColumns="true">
<mx:columns>
<mx:DataGridColumn dataField="old"
labelFunction="dataGridCol_labelFunc"
sortCompareFunction="test2_compareFunc" />
<mx:DataGridColumn dataField="new"
labelFunction="dataGridCol_labelFunc"
sortCompareFunction="test3_compareFunc" />
</mx:columns>
</mx:DataGrid>
</mx:Application>

下面是测试用代码：

Download: tests.xml
<?xml version="1.0" encoding="utf-8"?>
<tests>
<test name="group1">
<test2 name="old">One (old)</test2>
<test3 name="new">Un (new)</test3>
</test>
<test name="group2">
<test2 name="old">Two (old)</test2>
<test3 name="new">Deux (new)</test3>
</test>

<test name="group8">
<test2 name="old">Eight (old)</test2>
<test3 name="new">Huit (new)</test3>
</test>
</tests>

本文转自：http://blog.minidx.com/2008/04/10/699.html