android 网络广播 类似QQ动态检查网络

    private ConnectivityManager mConnectivityManager;
    private NetworkInfo netInfo; 

在onCreate 注册广播

 IntentFilter mFilter = new IntentFilter();  mFilter.addAction(ConnectivityManager.CONNECTIVITY_ACTION); registerReceiver(myNetReceiver, mFilter);

一定要在onDestroy()方法注销广播
    @Override
    public void onDestroy() {
        super.onDestroy();
        if(myNetReceiver!=null){
               unregisterReceiver(myNetReceiver);
        }
    }

rl_error_item是布局文件类似QQ列表显示的未连接网络状态XML布局

    private BroadcastReceiver myNetReceiver = new BroadcastReceiver() { 

         @Override
         public void onReceive(Context context, Intent intent) { 

          String action = intent.getAction();
                if (action.equals(ConnectivityManager.CONNECTIVITY_ACTION)) { 

                    mConnectivityManager = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
                    netInfo = mConnectivityManager.getActiveNetworkInfo();
                    if(netInfo != null && netInfo.isAvailable()) {
                         //网络连接
                        String name = netInfo.getTypeName();
                        if(netInfo.getType()==ConnectivityManager.TYPE_WIFI || netInfo.getType()==ConnectivityManager.TYPE_ETHERNET || netInfo.getType()==ConnectivityManager.TYPE_MOBILE){
                            //3g网络
                              rl_error_item.setVisibility(View.GONE);
                        }
                      } else {
                          //网络断开
                          rl_error_item.setVisibility(View.VISIBLE);
                    }
                } 

           }
    };