Android笔记之BroadCast判断网络状况

1、添加权限：

 <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

2、判断网络是否可用：

    private ConnectivityManager manager;

    private BroadcastReceiver receiver = new BroadcastReceiver() {

        @Override
        public void onReceive(Context context, Intent intent) {
            // TODO Auto-generated method stub
            // 通知用户网络连接变化
            NetworkInfo networkinfo = manager.getActiveNetworkInfo();  
            
               if (networkinfo == null || !networkinfo.isAvailable()) {  
                  Log.i("receive", "网络不可用");
               }  
            Log.i("MainActivity", "receive");
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        manager=(ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
    }

    // 注册广播
    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        IntentFilter filter=new IntentFilter();
        filter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
        registerReceiver(receiver, filter);
    }

    // 卸载广播
    @Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        if(receiver!=null){
            unregisterReceiver(receiver);
        }
    }

 3、更详细的网络信息

private BroadcastReceiver receiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            // TODO Auto-generated method stub
            // 提醒用户网络状况有异常
            // 分别获得2G和3G、wifi的网络状况
            //提醒用户的两种方式：吐司、通知
            NetworkInfo mobileInfo = manager
                    .getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
            NetworkInfo wifiInfo = manager
                    .getNetworkInfo(ConnectivityManager.TYPE_WIFI);
            if (!mobileInfo.isConnected() || !wifiInfo.isConnected()) {
                 Notification.Builder builder = new Notification.Builder(MainActivity.this);
                 builder.setContentText("提示信息");
                 builder.setContentText("网络状况有异常");
                 builder.setSmallIcon(R.drawable.ic_launcher);
                 notificationManager.notify(1001,builder.build());
            }
        }
    };

Done！