flex 监听网络连接情况

NativeApplication.nativeApplication.addEventListener(Event.NETWORK_CHANGE, onNetworkChange);
private var monitor:URLMonitor;
            public var urlStr:String;
            public function onNetworkChange(event:Event):void
            {
                trace("网络连接发生改变");
                //监视网络状态
                var url:URLRequest=new URLRequest(urlStr);
                url.method = "GET";
                monitor = new URLMonitor(url);
                monitor.addEventListener(StatusEvent.STATUS, onMonitor);
                monitor.start();
            } 
            private function onMonitor(event:Event):void 
            { 
                monitor.removeEventListener(StatusEvent.STATUS, onMonitor);
                trace("连接"+monitor.available); 
                if(monitor.available){
                    //网络连接可用
                    //处理联网操作 
                    setDataHandler();
                    papersViewId.initVu();
                    dispatchEvent(new NetOkEvent(NetOkEvent.NETOK_EVENT));
                } 
                else 
                { 
                    //网络连接不可用，相关处理 
                    dispatchEvent(new NetErrorEvent(NetErrorEvent.NETERROR_EVENT));
                } 
            }