在Flex中给datagrid添加右键菜单项的具体实现

<?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"
creationComplete="initApp()">
<s:layout>
<s:HorizontalLayout horizontalAlign="center" verticalAlign="middle"/>
</s:layout>
<fx:Script>
<![CDATA[
import mx.controls.Alert;
import mx.events.DataGridEvent;
import mx.events.FlexEvent;

import spark.events.GridEvent;
private var myContextMenu:ContextMenu;

private function initApp():void
{
popUpMenu();
}

private function popUpMenu():void
{
myContextMenu = new ContextMenu();
removeDefaultItems();
addCustomMenuItems();
//监听右键菜单弹出后的事件
myContextMenu.addEventListener(ContextMenuEvent.MENU_SELECT, menuSelectedHandler);
myDataGrid.contextMenu = myContextMenu;
}
//删除原有菜单项
private function removeDefaultItems():void
{
myContextMenu.hideBuiltInItems();
var defaultItems:ContextMenuBuiltInItems = myContextMenu.builtInItems;
defaultItems.print = false;
}
//添加用户自定义菜单项
private function addCustomMenuItems():void
{
var item:ContextMenuItem = new ContextMenuItem("删除行");
//默认的菜单项
item.visible = false;
myContextMenu.customItems.push(item);
//监听选择菜单项后的事件
item.addEventListener(ContextMenuEvent.MENU_ITEM_SELECT, itemSelectedHandler);
}
//弹出菜单后的事件处理函数
private function menuSelectedHandler(event:ContextMenuEvent):void
{
var item:ContextMenuItem = myContextMenu.customItems[0] as ContextMenuItem;

if (myDataGrid.selectedIndex >= 0)
{
item.visible = true;
}
else
{
item.visible = false;
}
}
//选择菜单项后的事件处理函数
private function itemSelectedHandler(event:ContextMenuEvent):void
{

if (myDataGrid.selectedIndex >= 0)
{
myDataGrid.dataProvider.removeItemAt(myDataGrid.selectedIndex);
}
}

]]>
</fx:Script>
<s:DataGrid requestedRowCount="4" id="myDataGrid"
width="500">
<s:columns>
<s:ArrayList>
<s:GridColumn dataField="dataField1" headerText="列 1" id="col1"></s:GridColumn>
<s:GridColumn dataField="dataField2" headerText="列 2"></s:GridColumn>
<s:GridColumn dataField="dataField3" headerText="列 3"></s:GridColumn>
</s:ArrayList>
</s:columns>
<s:typicalItem>
<fx:Object dataField1="示例数据" dataField2="示例数据" dataField3="示例数据"></fx:Object>
</s:typicalItem>
<s:ArrayList>
<fx:Object dataField1="数据1" dataField2="数据1" dataField3="数据1"></fx:Object>
<fx:Object dataField1="数据2" dataField2="数据2" dataField3="数据2"></fx:Object>
<fx:Object dataField1="数据3" dataField2="数据3" dataField3="数据3"></fx:Object>
<fx:Object dataField1="数据4" dataField2="数据4" dataField3="数据4"></fx:Object>
</s:ArrayList>
</s:DataGrid>

</s:Application>