Longitude and latitude are displayed as 0 in Android

  ************* TrackGPS.java *****************************  

    import android.app.AlertDialog;
    import android.app.Service;
    import android.content.Context;
    import android.content.DialogInterface;
    import android.content.Intent;

    import android.content.pm.PackageManager;
    import android.location.Location;
    import android.location.LocationListener;
    import android.location.LocationManager;
    import android.os.Bundle;
    import android.os.IBinder;
    import android.provider.Settings;
    import android.support.v4.app.ActivityCompat;
    import android.util.Log;
    import android.widget.Toast;

    /**
     * Created by ANQ on 8/8/2016.
     */

    public class TrackGPS extends Service implements LocationListener {

        private final Context mContext;


        boolean checkGPS = false;


        boolean checkNetwork = false;

        boolean canGetLocation = false;

        Location loc;
        double latitude;
        double longitude;


        private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10;


        private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1;
        protected LocationManager locationManager;

        public TrackGPS(Context mContext) {
            this.mContext = mContext;
            getLocation();
        }

        private Location getLocation() {

            try {
                locationManager = (LocationManager) mContext
                        .getSystemService(LOCATION_SERVICE);

                // getting GPS status
                checkGPS = locationManager
                        .isProviderEnabled(LocationManager.GPS_PROVIDER);

                // getting network status
                checkNetwork = locationManager
                        .isProviderEnabled(LocationManager.NETWORK_PROVIDER);

                if (!checkGPS && !checkNetwork) {
                    Toast.makeText(mContext, "No Service Provider Available", Toast.LENGTH_SHORT).show();
                } else {
                    this.canGetLocation = true;
                    // First get location from Network Provider
                    if (checkNetwork) {
                        Toast.makeText(mContext, "Network", Toast.LENGTH_SHORT).show();

                        try {
                            locationManager.requestLocationUpdates(
                                    LocationManager.NETWORK_PROVIDER,
                                    MIN_TIME_BW_UPDATES,
                                    MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                            Log.d("Network", "Network");
                            if (locationManager != null) {
                                loc = locationManager
                                        .getLastKNownLocation(LocationManager.NETWORK_PROVIDER);

                            }

                            if (loc != null) {
                                latitude = loc.getLatitude();
                                longitude = loc.getLongitude();
                            }
                        }
                        catch(SecurityException e){

                        }
                    }
                }
                // if GPS Enabled get lat/long using GPS Services
                if (checkGPS) {
                    Toast.makeText(mContext,"GPS",Toast.LENGTH_SHORT).show();
                    if (loc == null) {
                        try {
                            locationManager.requestLocationUpdates(
                                    LocationManager.GPS_PROVIDER,
                                    MIN_TIME_BW_UPDATES,
                                    MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                            Log.d("GPS Enabled", "GPS Enabled");
                            if (locationManager != null) {
                                loc = locationManager
                                        .getLastKNownLocation(LocationManager.GPS_PROVIDER);
                                if (loc != null) {
                                    latitude = loc.getLatitude();
                                    longitude = loc.getLongitude();
                                }
                            }
                        } catch (SecurityException e) {

                        }
                    }
                }

            } catch (Exception e) {
                e.printStackTrace();
            }

            return loc;
        }

        public double getLongitude() {
            if (loc != null) {
                longitude = loc.getLongitude();
            }
            return longitude;
        }

        public double getLatitude() {
            if (loc != null) {
                latitude = loc.getLatitude();
            }
            return latitude;
        }

        public boolean canGetLocation() {
            return this.canGetLocation;
        }

        public void showSettingsAlert() {
            AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);


            alertDialog.setTitle("GPS Not Enabled");

            alertDialog.setMessage("Do you wants to turn On GPS");


            alertDialog.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
                    mContext.startActivity(intent);
                }
            });


            alertDialog.setNegativeButton("No", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    dialog.cancel();
                }
            });


            alertDialog.show();
        }


        public void stopUsingGPS() {
            if (locationManager != null) {

                locationManager.removeUpdates(TrackGPS.this);
            }
        }

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

        @Override
        public void onLocationChanged(Location location) {

        }

        @Override
        public void onStatusChanged(String s, int i, Bundle bundle) {

        }

        @Override
        public void onProviderEnabled(String s) {

        }

        @Override
        public void onProviderDisabled(String s) {

        }
    }






************* MainActivity.java ****************

    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;

    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;
    import android.view.View;
    import android.widget.Button;
    import android.widget.Toast;

    public class MainActivity extends AppCompatActivity {

        private Button b_get;
        private TrackGPS gps;
        double longitude;
        double latitude;
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            b_get = (Button)findViewById(R.id.get);



            b_get.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {

                    gps = new TrackGPS(MainActivity.this);


                    if(gps.canGetLocation()){


                        longitude = gps.getLongitude();
                        latitude = gps .getLatitude();

                        Toast.makeText(getApplicationContext(),"Longitude:"+Double.toString(longitude)+"\nLatitude:"+Double.toString(latitude),Toast.LENGTH_SHORT).show();
                    }
                    else
                    {

                        gps.showSettingsAlert();
                    }

                }
            });
        }

        @Override
        protected void onDestroy() {
            super.onDestroy();
            gps.stopUsingGPS();
        }
    }

When I run the application, the latitude and longitude are displayed as 0.0, and I'm testing the application with Android marshmallows“ http://clover.studio/2016/08/09/getting-current-location-in-android-using-location-manager/ ”This is the link I used to create the application

resolvent:

Please manage the required marshmallow licenses

First, you add this permission to the manifest file

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

After your activity, first declare two variables like this,

 private static final int REQUEST_CODE_PERMISSION = 1;
 String mPermission = Manifest.permission.ACCESS_FINE_LOCATION;

After oncreate method

 if(Build.VERSION.SDK_INT>= 23) {

        if (checkSelfPermission(mPermission) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(MainActivity.this,
                    new String[]{mPermission,
                    },
                    REQUEST_CODE_PERMISSION);
            return;
        }

        else
        {
            *here manage your code if permission already access
        }
    }