how to connect bluetooth using AlarmManager Android

Question

I am working in Android with Bluetooth. I can obtain a connection and results from bluetooth device inside MainActivity

now, i want to connect and to interact with the bluetoth device from a AlarManager when app is dead.

actually, i have the source but runtimes do not match

what is my problem? The Thread of BackgroundService does not wait the Thread of bluetooth. I use Thread.sleep(2000); for to wait the bluetooth.

The bluetooth connect and connects and returns the information but I can not process the result because BackgroundService dies first

(BluetoothLeService extend from Service)

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Intent alarm = new Intent(this, AlarmReceiver.class);
        boolean alarmRunning = (PendingIntent.getBroadcast(this, 0, alarm, PendingIntent.FLAG_NO_CREATE) != null);
        if (alarmRunning == false) {
            PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0, alarm, 0);
            AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
            alarmManager.setRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime(), 120000, pendingIntent); // 1800000
        }
    }
}

My BroadcastReceiver

public class AlarmReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        Intent background = new Intent(context, BackgroundService.class);
        context.startService(background);
    }
}

My BackgroundService

public class BackgroundService extends Service {
    private boolean isRunning;
    private Thread backgroundThread;
    private CommandManager manager;
    private BluetoothLeService mBluetoothLeService;

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public void onCreate() {
        this.isRunning = false;
        manager = CommandManager.getInstance(getApplicationContext());
        Intent bindIntent = new Intent(getApplicationContext(), BluetoothLeService.class);
        bindService(bindIntent, mServiceConnection, Context.BIND_AUTO_CREATE);
        LocalBroadcastManager.getInstance(getApplicationContext()).registerReceiver(
                BLEStatusChangeReceiver, makeGattUpdateIntentFilter());
        this.backgroundThread = new Thread(myTask);
    }

    private Runnable myTask = new Runnable() {
        public void run() {
            // Do something here
            manager.findBand();

            try {
                Thread.sleep(2000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            manager.getDataFromDevice();// for obtain data from bluetooth

            stopSelf();
        }
    };


    @Override
    public void onDestroy() {
        Log.e("onDestroy","prepared");
        try { Thread.sleep(15000); }
        catch (InterruptedException e) { e.printStackTrace(); }

        Log.e("onDestroy","YES");
        unbindService(mServiceConnection);
        this.isRunning = false;
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        if(!this.isRunning) {
            this.isRunning = true;
            this.backgroundThread.start();
        }
        return START_STICKY;
    }

    // Code to manage Service lifecycle.
    private final ServiceConnection mServiceConnection = new ServiceConnection() {
        @Override
        public void onServiceConnected(ComponentName componentName, IBinder service) {
            mBluetoothLeService = ((BluetoothLeService.LocalBinder) service).getService();
            Log.i("STATUS", "onServiceConnected---==---");
            if (!mBluetoothLeService.initialize()) {
                Log.e("STATUS BLUETOOTH", "Unable to initialize Bluetooth");
            }
            mBluetoothLeService.connect("mac device here", false);
        }

        @Override
        public void onServiceDisconnected(ComponentName componentName) {
            mBluetoothLeService = null;
            Log.i("STATUS", "onServiceDisconnected");
        }
    };

    private final BroadcastReceiver BLEStatusChangeReceiver = new BroadcastReceiver() {
        @SuppressLint("UseValueOf")
        public void onReceive(Context context, Intent intent) {
            /**
             * HERE RECEPTION DATA BLUETOOTH
             */
        }
    };

    private IntentFilter makeGattUpdateIntentFilter() {
        final IntentFilter intentFilter = new IntentFilter();
        intentFilter.addAction(BroadcastCommand.ACTION_DATA_AVAILABLE);
        intentFilter.addAction(BroadcastCommand.ACTION_GATT_CONNECTED);
        intentFilter.addAction(BroadcastCommand.ACTION_GATT_DISCONNECTED);
        return intentFilter;
    }

}

PD: I hope it is enough information ... if I miss something, I'll respond soon

Answer 1

You should either move to a Foreground service or acquire a PowerManager.WakeLock before launching your Service and release it when your task is done. However, still some resource access might be limited while the phone is in Doze mode.