TCPSocket Service stops on device sleep mode

Question

I have a bounded service which performs TCP Socket connection and sends some data repeatedly. After the device goes into sleep mode thread stops and so the data send. What am I doing wrong?

As far as I know, service bounded to the Main Activity has to be START_STICKY but that doesn't fix my problem.

MainActivity class where the service is bounded and the connect button click starts socket sending thread in the AsyncTask:

public class MainActivity extends AppCompatActivity {

public MainActivity() {
    super();
}

private CTIController CTIControl;
protected boolean mBound = false;

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

@Override
protected void onStart() {
    super.onStart();

    Intent intent = new Intent(this, CTIController.class);
    bindService(intent, mConnection, Context.BIND_AUTO_CREATE);
}

@Override
protected void onStop() {
    super.onStop();
    if (mBound) {
        //disconnect socket and stop sending thread         
        CTIControl.GetControllersFactory().GetCTI2Controller().OnDisconnect();          
        unbindService(mConnection);
        mBound = false;
    }
}

private ServiceConnection mConnection = new ServiceConnection() {
    @Override
    public void onServiceConnected(ComponentName name, IBinder service) {
        LocalBinder binder = (LocalBinder) service;
        CTIControl = binder.getService();
        mBound = true;
    }

    @Override
    public void onServiceDisconnected(ComponentName name) {
         mBound = false;
    }
};

/** Callled when the user clicks connect button */
public void ConnectClick(View view) {                       
    new ConnectOperation().execute("");     
}

private class ConnectOperation extends AsyncTask<String, Void, String> {
    @Override
    protected String doInBackground(String... params) {
        EditText ip = (EditText)findViewById(R.id.ip);
        EditText port = (EditText)findViewById(R.id.port);

        //start socket connection and run sending thread
        CTIControl.TryConnect(ip.getText().toString(), port);

        return "Executed";
    }   
}

The CTIController Service which controls the Socket connection:

public class CTIController extends Service implements ICTIController {  

private final IBinder mBinder = new LocalBinder();

public TryConnect(String ipAddress, int port) throws IOException{

    this.ClientSocket = new Socket();
    this.ClientSocket.connect(new InetSocketAddress(ipAddress, port), 10000);
    //... start sending data repeatedly

}

public class LocalBinder extends Binder {
    public CTIController getService() {
        return CTIController.this;
    }
}

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

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

        return START_STICKY;
    }
}

And my manifest file:

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.PERSISTENT_ACTIVITY" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS" />

<application
    android:allowBackup="true"
    android:persistent="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <service android:name=".controller.CTIController" android:exported="false"/>
    <activity
        android:name=".MainActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>

</manifest>

Answer 1

Do change in onStartCommand of your service.

return START_REDELIVER_INTENT; instead of return START_STICKY;

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

       return START_REDELIVER_INTENT;
    }
}