/*
*初始化mqttclient
*/
private void init() {
    try {
      //MQTT的連接設置
      options = new MqttConnectOptions();
      //host為主機名，test為clientid即連接MQTT的客戶端ID，一般以客戶端唯一標識符表示，MemoryPersistence設置clientid的保存形式，默認為以內存保存
      client = new MqttClient(new Ip().host, username,
          new MemoryPersistence());
      //設置是否清空session,這里如果設置為false表示服務器會保留客戶端的連接記錄，這里設置為true表示每次連接到服務器都以新的身份連接
      options.setCleanSession(false);
//options.setWill(myTopic,null,2,false);

      //設置連接的用戶名
      options.setUserName(login_token);
      //設置連接的密碼
      options.setPassword(passWord.toCharArray());
      // 設置超時時間 單位為秒
      options.setConnectionTimeout(10);
      // 設置會話心跳時間 單位為秒 服務器會每隔1.5*20秒的時間向客戶端發(fā)送個消息判斷客戶端是否在線，但這個方法并沒有重連的機制
      options.setKeepAliveInterval(60);
      //設置回調
      client.setCallback(new MqttCallback() {
        @Override
        public void connectionLost(Throwable cause) {
          //連接丟失后，一般在這里面進行重連
          System.out.println("connectionLost----------");

        }

        @Override
        public void deliveryComplete(IMqttDeliveryToken token) {
          //publish后會執(zhí)行到這里
          System.out.println("deliveryComplete---------"
              + token.isComplete());
        }
        @Override
        public void messageArrived(String topicName, MqttMessage message)
            throws Exception {
          byte[] message1 = message.getPayload();
          // subscribe后得到的消息會執(zhí)行到這里面
          System.out.println("messageArrived----------" + message1[0] + Arrays.toString(message1));
          System.out.println(message1[0] == 5);
          String id = new String(subBytes(message1, 1, 16), "UTF-8");

          System.out.print("mqtt收到的id" + id);
          DeviceList device = getBookById(id);
          System.out.print("device" + device.getName());
          String name = device.getName();
          String gName = device.getgName();
          String type = device.getType();
          System.out.print("名字為" + name + gName);
          /**
          * 使用handler發(fā)送matt接收的消息，格式為二進制數(shù)據(jù)
          * */

          Message msg = new Message();
          msg.what = 1;
          if (message1[0] == 1) {
//            msg.obj = name + "設備心跳";
//            handler.sendMessage(msg);
            return;
          }
          if (message1[0] == 2) {
            msg.obj = gName + "" + name + "報警";
            msg.arg1 = Integer.parseInt(type);
            handler.sendMessage(msg);
            return;
          }
          if (message1[0] == 3) {
            msg.obj = gName + "" + name + "上線";
            handler.sendMessage(msg);
            return;
          }
          if (message1[0] == 4) {
            msg.obj = gName + "" + name + "離線";
            handler.sendMessage(msg);
            return;
          }
          if (message1[0] == 5) {
            if (message1[17] == 0) {
              msg.obj = gName + "" + name + "關門";
            } else {
              msg.obj = gName + "" + name + "開門";
            }


            handler.sendMessage(msg);
            return;
          }
          if (message1[0] == 20 && message1[17] > 0 && message1[17] < 20) {

            msg.obj = name + "電池電量: " + message1[17] + "%";
            handler.sendMessage(msg);
            System.out.println("電池:" + name + "電池電量: " + message1[17] + "%");
            return;
          }
          if (message1[17] > 0) {
            SharedPreferences sp = getActivity().getSharedPreferences(id, getActivity().MODE_PRIVATE);
            // 獲得sp的編輯器
            SharedPreferences.Editor ed = sp.edit();
            // 以鍵值對的顯示將用戶名和密碼保存到sp中
            ed.putString("battery", String.valueOf(message1[17]));
            // 提交用戶名和密碼
            ed.commit();
          }
        }
      });
    } catch (Exception e) {
      e.printStackTrace();
    }
  }

  public byte[] subBytes(byte[] src, int begin, int count) {
    byte[] bs = new byte[count];
    System.arraycopy(src, begin, bs, 0, count);
    return bs;
  }

  //根據(jù)id拿到屬性為id的Book對象。
  public static DeviceList getBookById(String id) {
    DeviceList book = new DeviceList();
    book.setId(id);//設置傳入的id值
    //books.indexOf()根據(jù)id比較對象是否相等
    return deviceList1.get(deviceList1.indexOf(book));
    //返回關聯(lián)id的Book對象。
  }
  
  private void connect() {
    new Thread(new Runnable() {

      @Override
      public void run() {
        try {
          client.connect(options);
          Message msg = new Message();
          msg.what = 2;
          handler.sendMessage(msg);
        } catch (Exception e) {
          e.printStackTrace();
          Message msg = new Message();
          msg.what = 3;
          handler.sendMessage(msg);
        }
      }
    }).start();
  }

  protected boolean onKeyDown(int keyCode, KeyEvent event) {
    if (client != null && keyCode == KeyEvent.KEYCODE_BACK) {
      try {
        client.disconnect();
      } catch (Exception e) {
        e.printStackTrace();
      }
    }
    return super.getActivity().onKeyDown(keyCode, event);
  }

  @Override
  public void onDestroy() {
    super.onDestroy();
    try {
      scheduler.shutdown();
      client.disconnect();
    } catch (MqttException e) {
      e.printStackTrace();
    }
  }

  private void startReconnect() {
    scheduler = Executors.newSingleThreadScheduledExecutor();
    scheduler.scheduleAtFixedRate(new Runnable() {

      @Override
      public void run() {
        if (!client.isConnected()) {
          connect();
        }
      }
    }, 0 * 1000, 10 * 1000, TimeUnit.MILLISECONDS);
  }
其次使用handlermessage接收消息，并已notifacation的形式展示在通知欄頁面
 handler = new Handler() {
      @Override
      public void handleMessage(Message msg) {
        super.handleMessage(msg);
        if (msg.what == 1) {
          NotificationManager manager = (NotificationManager) getActivity().getSystemService(Context.NOTIFICATION_SERVICE);
          Notification myNotify = new Notification();
          myNotify.icon = R.drawable.logo;
          myNotify.tickerText = "新消息";
          myNotify.when = System.currentTimeMillis();
          //使用默認的聲音
          myNotify.defaults |= Notification.DEFAULT_SOUND;

//使用默認的震動
          myNotify.defaults |= Notification.DEFAULT_VIBRATE;

//使用默認的聲音、振動、閃光
          myNotify.defaults = Notification.DEFAULT_ALL;
// myNotify.flags=Notification.FLAG_AUTO_CANCEL;
          // myNotify.flags = Notification.FLAG_NO_CLEAR;// 不能夠自動清除
          RemoteViews rv = new RemoteViews(getActivity().getPackageName(),
              R.layout.activity_notification1);
          rv.setTextViewText(R.id.tv_desc, (String) msg.obj);
          myNotify.contentView = rv;
          Intent intent = new Intent(getActivity(), MainActivity.class);
          //  intent.addCategory(Intent.CATEGORY_LAUNCHER);
          //  intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
          android.app.PendingIntent contentIntent = android.app.PendingIntent.getActivity(getActivity(), 0,
              intent, 0);
          myNotify.contentIntent = contentIntent;
          manager.notify(i1++, myNotify);
          PowerManager pm = (PowerManager) getActivity().getSystemService(Context.POWER_SERVICE);
          PowerManager.WakeLock wakeLock = pm.newWakeLock(PowerManager.ACQUIRE_CAUSES_WAKEUP |
              PowerManager.SCREEN_DIM_WAKE_LOCK, "target");
          boolean screen = pm.isScreenOn();
          if (!screen) {//如果滅屏
            wakeLock.acquire();
            wakeLock.release();
          }
          refresh();
        } else if (msg.what == 2) {
          System.out.println("連接成功");
          System.out.print("連接成功大小" + listDatas2.size());
          try {
            client.subscribe(myTopic, 1);
            client.subscribe(myTopic1, 1);
          } catch (MqttException e) {
            e.printStackTrace();
          }
        } else if (msg.what == 3) {
          //Toast.makeText(MainActivity.this, "連接失敗，系統(tǒng)正在重連", Toast.LENGTH_SHORT).show();
          System.out.println("連接失敗，系統(tǒng)正在重連");
        }
      }
    };