@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    textView = (TextView) findViewById(R.id.textView);
    IntentFilter filter = new IntentFilter();
    filter.addAction("SOME_ACTION");
    receiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            textView.setText("hey");
        }
    };
    registerReceiver(receiver, filter);
    buttonStart = (Button) findViewById(R.id.start);
    buttonStart.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            startService(new Intent(MainActivity.this, LocalService.class));
        }
    });
}

@Override
protected void onDestroy() {
    super.onDestroy();
    unregisterReceiver(receiver);
}

public class LocalService extends Service
{
    private static Timer timer = new Timer();

    public IBinder onBind(Intent arg0)
    {
        return null;
    }

    public void onCreate()
    {
        super.onCreate();
        startService();
    }

    private void startService()
    {
        timer.scheduleAtFixedRate(new mainTask(), 0, 5000);
    }

    private class mainTask extends TimerTask
    {
        public void run()
        {
            Intent intent = new Intent();
            intent.setAction("SOME_ACTION");
            sendBroadcast(intent);
        }
    }

    public void onDestroy()
    {
        super.onDestroy();
    }
}