ActionScript-Flex：点击表格中的“确认”按钮，为什么页面显示没变呢

Question

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" 
               xmlns:s="library://ns.adobe.com/flex/spark" 
               xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
    <fx:Declarations>
        <!-- 将非可视元素（例如服务、值对象）放在此处 -->
    </fx:Declarations>
    
    <fx:Script>
        <![CDATA[
            import mx.collections.ArrayCollection;
            import mx.controls.Alert;
            //绑定表格用的数据  
            [Bindable]
            private var arr:ArrayCollection = new ArrayCollection([
                {neName:"教工路文一路路口相机_4", neType:"相机" , neAlarmType:"设备告警" , removeStatus:"未清除" , confirmStatus:"未确认" , neAlarmGrade:"2级"},
                {neName:"学院路文一路路口相机_3", neType:"相机" , neAlarmType:"环境告警" , removeStatus:"未清除" , confirmStatus:"未确认" , neAlarmGrade:"3级"},
                {neName:"文一路莫干山路路口相机_1", neType:"相机" , neAlarmType:"连接通信告警" , removeStatus:"未清除" , confirmStatus:"未确认" , neAlarmGrade:"1级"},
                {neName:"文一路莫干山路路口相机_3", neType:"相机" ,  neAlarmType:"性能告警" , removeStatus:"未清除" , confirmStatus:"未确认" , neAlarmGrade:"4级"}
            ]); 
            
            //删除告警信息
            public function deleteAlarmRecord():void{
                arr.removeItemAt(alarmGrid.selectedIndex);
            }
            //确认告警信息
            public function confirmAlarmInfo():void{
                arr.getItemAt(alarmGrid.selectedIndex).confirmStatus = "已确认";
                alarmGrid.dataProvider=arr;
            }
        ]]>
    </fx:Script>
    
    <s:DataGrid id="alarmGrid" width="600" height="285" requestedRowCount="4" dataProvider="{arr}">
        <s:columns>
            <s:ArrayList>
                <s:GridColumn dataField="neName" headerText="名称"></s:GridColumn>
                <s:GridColumn dataField="neType" headerText="类型"></s:GridColumn>
                <s:GridColumn dataField="removeStatus" headerText="清除状态"></s:GridColumn>
                <s:GridColumn dataField="confirmStatus" headerText="确认状态"></s:GridColumn>
                <s:GridColumn headerText="操作">
                    <s:itemRenderer>
                        <fx:Component>
                            <s:GridItemRenderer>
                                <s:HGroup> 
                                    <mx:LinkButton toolTip="清除" label="清除" click="outerDocument.deleteAlarmRecord();" textDecoration="underline" color="#2066CF" fontWeight="normal"/> 
                                    <mx:LinkButton toolTip="确认" label="确认" click="outerDocument.confirmAlarmInfo()" textDecoration="underline" color="#2066CF" fontWeight="normal"/> 
                                </s:HGroup>
                            </s:GridItemRenderer>
                        </fx:Component>
                    </s:itemRenderer>
                </s:GridColumn>
            </s:ArrayList>
        </s:columns>
    </s:DataGrid>
    
</s:Application>

Answer 1

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
<fx:Declarations>
<!-- 将非可视元素（例如服务、值对象）放在此处 -->
</fx:Declarations>

<fx:Script>
<![CDATA[
import mx.collections.ArrayCollection;
//绑定表格用的数据
[Bindable]
private var arr:ArrayCollection = new ArrayCollection([
{neName:"教工路文一路路口相机_4", neType:"相机" , neAlarmType:"设备告警" , removeStatus:"未清除" , confirmStatus:"未确认" , neAlarmGrade:"2级"},
{neName:"学院路文一路路口相机_3", neType:"相机" , neAlarmType:"环境告警" , removeStatus:"未清除" , confirmStatus:"未确认" , neAlarmGrade:"3级"},
{neName:"文一路莫干山路路口相机_1", neType:"相机" , neAlarmType:"连接通信告警" , removeStatus:"未清除" , confirmStatus:"未确认" , neAlarmGrade:"1级"},
{neName:"文一路莫干山路路口相机_3", neType:"相机" , neAlarmType:"性能告警" , removeStatus:"未清除" , confirmStatus:"未确认" , neAlarmGrade:"4级"}
]);

//删除告警信息
public function deleteAlarmRecord():void
{
arr.removeItemAt(alarmGrid.selectedIndex);
}
//确认告警信息
public function confirmAlarmInfo(item:Object):void
{
item.confirmStatus = "已确认";
arr.itemUpdated(item);
}
]]>
</fx:Script>

<s:DataGrid id="alarmGrid" width="600" height="285" requestedRowCount="4" dataProvider="{arr}">
<s:columns>
<s:ArrayList>
<s:GridColumn dataField="neName" headerText="名称"></s:GridColumn>
<s:GridColumn dataField="neType" headerText="类型"></s:GridColumn>
<s:GridColumn dataField="removeStatus" headerText="清除状态"></s:GridColumn>
<s:GridColumn dataField="confirmStatus" headerText="确认状态"></s:GridColumn>
<s:GridColumn headerText="操作">
<s:itemRenderer>
<fx:Component>
<s:GridItemRenderer>
<s:HGroup>
<mx:LinkButton toolTip="清除" label="清除" click="outerDocument.deleteAlarmRecord();" textDecoration="underline" color="#2066CF" fontWeight="normal"/>
<mx:LinkButton toolTip="确认" label="确认" click="outerDocument.confirmAlarmInfo(data)" textDecoration="underline" color="#2066CF" fontWeight="normal"/>
</s:HGroup>
</s:GridItemRenderer>
</fx:Component>
</s:itemRenderer>
</s:GridColumn>
</s:ArrayList>
</s:columns>
</s:DataGrid>

</s:Application>

只是改变了对象的值，并没有通知控件更新，所以没有变化。
这种问题一般就两个思路，一是如上面代码所示，修改值之后手动通知组件更新；二是把组件的属性与对象的值绑定，通过对象的public方法来修改其属性值。