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How I can create a Background service in android?

I need to create a service that allow my application to work also when I close it, I've tried with STICKY_SERVICE but it doesn't work... if anyone can decribe me how I can do this please answer this question.

It works with android 7.1 and it doesn't with other versions

Here is my code...

public class SensorService extends Service {
public int counter=0;

public SensorService(Context applicationContext) {
    super();
    Log.i("HERE", "here I am!");
}

public SensorService() {
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    super.onStartCommand(intent, flags, startId);
    startTimer();
    return START_STICKY;
}

@Override
public void onDestroy() {
    super.onDestroy();
    Log.i("EXIT", "ondestroy!");
    stoptimertask();
    Intent broadcastIntent = new Intent("RestartSensor");
    sendBroadcast(broadcastIntent);
}

private Timer timer;
private TimerTask timerTask;
long oldTime=0;
public void startTimer() {
    //set a new Timer
    timer = new Timer();

    //initialize the TimerTask's job
    initializeTimerTask();

    //schedule the timer, to wake up every 1 second
    timer.schedule(timerTask, 1000, 1000); //
}

/**
 * it sets the timer to print the counter every x seconds
 */
public void initializeTimerTask() {
    timerTask = new TimerTask() {
        public void run() {
            Log.i("in timer", "in timer ++++  "+ (counter++));
        }
    };
}

/**
 * not needed
 */
public void stoptimertask() {
    //stop the timer, if it's not already null
    if (timer != null) {
        timer.cancel();
        timer = null;
    }
}

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

This is my service Restarter...

public class SensorRestarterBroadcastReceiver extends BroadcastReceiver {

@Override
public void onReceive(Context context, Intent intent) {
    Log.i(SensorRestarterBroadcastReceiver.class.getSimpleName(), "Service Stops");
    context.startService(new Intent(context, SensorService.class));
}
}

And the mainClass

public class MainActivity extends AppCompatActivity {

Intent mServiceIntent;
private SensorService mSensorService;

Context ctx;

public Context getCtx() {
    return ctx;
}


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    ctx = this;
    setContentView(R.layout.activity_main);
    mSensorService = new SensorService(getCtx());
    mServiceIntent = new Intent(getCtx(), mSensorService.getClass());
    if (!isMyServiceRunning(mSensorService.getClass())) {
        startService(mServiceIntent);
    }
}

private boolean isMyServiceRunning(Class<?> serviceClass) {
    ActivityManager manager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
    for (ActivityManager.RunningServiceInfo service : manager.getRunningServices(Integer.MAX_VALUE)) {
        if (serviceClass.getName().equals(service.service.getClassName())) {
            Log.i ("isMyServiceRunning?", true+"");
            return true;
        }
    }
    Log.i ("isMyServiceRunning?", false+"");
    return false;
}


@Override
protected void onDestroy() {
    stopService(mServiceIntent);

    Log.i("MAINACT", "onDestroy!");
    super.onDestroy();
}
}

This restartthe service correctly but after 3/4 seconds it die.

I've added this to my manifest

<service
        android:name=".SensorService"
        android:enabled="true" >
    </service>

    <receiver
        android:name=".SensorRestarterBroadcastReceiver"
        android:enabled="true"
        android:exported="true"
        android:label="RestartServiceWhenStopped">
        <intent-filter>
            <action android:name="RestartSensor"/>
        </intent-filter>
    </receiver>

Add the following code to your sensor service and edit as per your need. You need to bind the sticky service to a notification to keep the service alive and start in the foreground.

@Override public void onCreate() { super.onCreate();

 Intent notifIntent = new Intent(this, SensorService.class); PendingIntent pi = PendingIntent.getActivity(this, 0, notifIntent, 0); Notification notification = new NotificationCompat.Builder(this) .setSmallIcon(R.drawable.smslogo_100x100) .setColor(ContextCompat.getColor(this, R.color.colorAccent)) .setContentTitle(getResources().getString(R.string.app_name)) .setContentText("Running") .setContentIntent(pi) .build(); startForeground(101010, notification); }

This will rectify the issue you are facing and the service will run forever.

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