AIR检测网络

    package com.juyou.util.net
    {
        import flash.events.StatusEvent;
        import flash.net.URLRequest;  

        import air.net.URLMonitor;
        /**
         * 网络监听
         *
         */
        public class NetChecker
        {
            private static var request:URLRequest = new URLRequest("http://www.baidu.com");
            private static var monitor:URLMonitor;
            /**检测间隔时间*/
            public static var _interval:Number = 10000;
            private static var available:Boolean = true;
            private static var observerList:Vector.<INetObserver> = new Vector.<INetObserver>();
            public function NetChecker()
            {  

            }
            /**
             * 注册观察者对象
             * @param obj    观察者对象
             */
            public static function attach(obj:INetObserver):void
            {
                if(observerList.indexOf(obj) == -1)
                {
                    observerList.push(obj);
                }
            }  

            /**
             * 删除观察者对象
             * @param obj    观察者对象
             */
            public static function detach(obj:INetObserver):void{
                var index:int = observerList.indexOf(obj);
                if(index == -1)
                    return;
                observerList.splice(index,1);
            }  

            /**
             * 通知所有注册的观察者对象
             */
            private static function nodifyObservers():void{
                for each(var obj:INetObserver in observerList)
                {
                    obj.updateNetAvailable(available);
                }
            }  

            /**
             * 开始监听网络状况
             *
             */
            public static function monitorNetwork():void
            {
                if(!monitor)
                    monitor = new URLMonitor(request);
                monitor.pollInterval = _interval;
                monitor.addEventListener(StatusEvent.STATUS,onStatusHandler);
                monitor.start();
            }  

            /**
             * 设置监听网络间隔
             * @param val
             *
             */
            public static function set interval(val:Number):void
            {
                if(_interval == val)return;
                _interval = val;
                if(monitor && monitor.running)
                {
                    monitor.stop();
                    monitor.pollInterval = _interval;
                    monitor.start();
                }
            }  

            public static function get interval():Number
            {
                return _interval;
            }  

            /**
             * 停止监听网络状态
             *
             */
            public static function stopMonitor():void
            {
                if(monitor)
                    monitor.stop();
            }  

            /**
             * 判断当前网络是否可用
             * @return
             *
             */
            public static function get networkAvailable():Boolean
            {
                return available;
            }  

            private static function onStatusHandler(e:StatusEvent):void
            {
    //          trace( ">>onStatusEvent::evt.code=" + e );
                if(e.level == "status")
                {
                    var flag:Boolean = false;
                    if(monitor.available && !available)
                    {
                        trace("网络已连接");
                        available = true;
                        flag = true;
                    }
                    else if(!monitor.available && available)
                    {
                        available = false;
                        trace("没有检测到网络");
                        flag = true;
                    }  

                    if(flag)
                    {
                        nodifyObservers();
                    }
                }  

            }  

        }
    }  

    package
    {
        public interface INetObserver
        {
            function updateNetAvailable(ava:Boolean):void;
        }
    }