mLastKnownLocation возвращает ноль при отладке в журнале

Question

Я сделал проект с картой для отображения моего текущего местоположения в моем приложении, и когда я запускаю свое приложение, он отображает карту, но он не отображает мое текущее местоположение на моем эмуляторе, затем я отладил mLastKnownLocation, и он возвращает нуль , тогда я хотел бы знать, если что-то отсутствует в моем проекте, зная, что мой Wi-Fi включен, разрешение предоставляется с:

   <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

и у меня включен сервис google play

Моя картаДействие

    package com.example.tibdev.maps;

import android.Manifest;
import android.content.pm.PackageManager;
import android.location.Location;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.support.v4.content.ContextCompat;
import android.util.Log;

import com.google.android.gms.location.FusedLocationProviderClient;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback {

    private static final int PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION = 1;
    private boolean mLocationPermissionGranted;
    private Location mLastKnownLocation;
    private FusedLocationProviderClient mFusedLocationProviderClient;
    private GoogleMap mMap;
    private LatLng mDefaultLocation;
    public static float DEFAULT_ZOOM = 19;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_maps);
        // Obtain the SupportMapFragment and get notified when the map is ready to be used.
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);

        // Construct a FusedLocationProviderClient.
        mFusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this);
    }


    /**
     *
     * @param googleMap
     * start the map in the view
     */
    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;

        // Turn on the My Location layer and the related control on the map.
        updateLocationUI();

        // Get the current location of the device and set the position of the map.
        getDeviceLocation();

    }

    /**
     *
     * @param requestCode
     * @param permissions
     * @param grantResults
     * Callback for the result from requesting permissions.
     */

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        this.mLocationPermissionGranted = false;

        switch (requestCode) {
            case PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION : {
                //si le tableau pour les permission est vide
                if(grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    this.mLocationPermissionGranted = true;
                }
            }
        }

        this.updateLocationUI();
    }

    /**
     * for get the permission for the location of user
     */
    private void getLocationPermission() {
        if(ContextCompat.checkSelfPermission(this.getApplicationContext(), Manifest.permission.ACCESS_FINE_LOCATION)
                == PackageManager.PERMISSION_GRANTED) {
            this.mLocationPermissionGranted = true;
        } else {
            ActivityCompat.requestPermissions(this,
                    new String[]{android.Manifest.permission.ACCESS_FINE_LOCATION},
                    PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION);
        }
    }

    /**
     * Get the best and most recent location of the device, which may be null in rare
     * cases when a location is not available.
     */
    public void getDeviceLocation() {
        try {
            if(mLocationPermissionGranted) {
                Task locationResult = mFusedLocationProviderClient.getLastLocation();
                locationResult.addOnCompleteListener(this, new OnCompleteListener() {
                    @Override
                    public void onComplete(@NonNull Task task) {
                        if(task.isSuccessful()) {
                            mLastKnownLocation = (Location) task.getResult();
                            Log.d("MapsDebug", "Result : " + mLastKnownLocation);
                            if(mLastKnownLocation != null) {
                                // Add a marker and move the camera
                                LatLng location = new LatLng(mLastKnownLocation.getLatitude(), mLastKnownLocation.getLongitude());
                                mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(location, DEFAULT_ZOOM));
                                mMap.addMarker(new MarkerOptions().position(location).title("Your Position"));
                                mMap.moveCamera(CameraUpdateFactory.newLatLng(location));
                            }
                        } else {
                            Log.d("MapsError", "Current location is null. Using defaults.");
                            Log.e("MapsError", "Exception: %s", task.getException());
                            mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(mDefaultLocation, DEFAULT_ZOOM));
                            mMap.getUiSettings().setMyLocationButtonEnabled(false);
                        }
                    }
                });
            }

        } catch(SecurityException e) {
            Log.e("Exception: %s", e.getMessage());
        }
    }

    /**
     * Updates the map's UI settings based on whether the user has granted location permission.
     */
    private void updateLocationUI() {
        if (mMap == null) {
            return;
        }
        try {
            if (mLocationPermissionGranted) {
                mMap.setMyLocationEnabled(true);
                mMap.getUiSettings().setMyLocationButtonEnabled(true);
            } else {
                mMap.setMyLocationEnabled(false);
                mMap.getUiSettings().setMyLocationButtonEnabled(false);
                this.mLastKnownLocation = null;
                getLocationPermission();
            }
        } catch (SecurityException e)  {
            Log.e("Exception: %s", e.getMessage());
        }
    }
}