获取用户的当前位置并存储在Firebase数据库上

Question

I working on android app and I want the user when he/she open specific activity the app get the location of the user or the latitude and longitude of the user without using google map activity or even open it i use this code but with no result

 LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
    if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
        return;
    }
    if (lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER)) {
        lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, new android.location.LocationListener() {
            @Override
            public void onLocationChanged(Location location) {
                 latitude = location.getLatitude();
                 longitude = location.getLongitude();
                LatLng latLng = new LatLng(latitude, longitude);
                Log.i("loc", latitude+"::"+longitude);

            }

            @Override
            public void onStatusChanged(String provider, int status, Bundle extras) {

            }

            @Override
            public void onProviderEnabled(String provider) {

            }

            @Override
            public void onProviderDisabled(String provider) {

            }
        });
    } else if (lm.isProviderEnabled(lm.GPS_PROVIDER)) {
        lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, new android.location.LocationListener() {
            @Override
            public void onLocationChanged(Location location) {
                latitude = location.getLatitude();
                longitude = location.getLongitude();
                LatLng latLng = new LatLng(latitude, longitude);
                Log.i("loc", latitude+"::"+longitude);

            }

            @Override
            public void onStatusChanged(String provider, int status, Bundle extras) {

            }

            @Override
            public void onProviderEnabled(String provider) {

            }

            @Override
            public void onProviderDisabled(String provider) {

            }
        });
    }

I put this code in my oncreate method but the value also be 0.0

thanks in advance

Answer 1

The Location tracker service

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

        private Location getLocation() {

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

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

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

                if (!checkGPS && !checkNetwork) {
                    Toast.makeText(mContext, "No Service Provider is available", Toast.LENGTH_SHORT).show();
                } else {
                    this.canGetLocation = true;

                    // if GPS Enabled get lat/long using GPS Services
                    if (checkGPS) {

                        if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                            // TODO: Consider calling
                            //    ActivityCompat#requestPermissions
                            // here to request the missing permissions, and then overriding
                            //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
                            //                                          int[] grantResults)
                            // to handle the case where the user grants the permission. See the documentation
                            // for ActivityCompat#requestPermissions for more details.
                        }
                        locationManager.requestLocationUpdates(
                                LocationManager.GPS_PROVIDER,
                                MIN_TIME_BW_UPDATES,
                                MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                        if (locationManager != null) {
                            loc = locationManager
                                    .getLastKnownLocation(LocationManager.GPS_PROVIDER);
                            if (loc != null) {
                                latitude = loc.getLatitude();
                                longitude = loc.getLongitude();
                            }
                        }


                    }


                    /*if (checkNetwork) {


                        if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                            // TODO: Consider calling
                            //    ActivityCompat#requestPermissions
                            // here to request the missing permissions, and then overriding
                            //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
                            //                                          int[] grantResults)
                            // to handle the case where the user grants the permission. See the documentation
                            // for ActivityCompat#requestPermissions for more details.
                        }
                        locationManager.requestLocationUpdates(
                                LocationManager.NETWORK_PROVIDER,
                                MIN_TIME_BW_UPDATES,
                                MIN_DISTANCE_CHANGE_FOR_UPDATES, this);

                        if (locationManager != null) {
                            loc = locationManager
                                    .getLastKnownLocation(LocationManager.NETWORK_PROVIDER);

                        }

                        if (loc != null) {
                            latitude = loc.getLatitude();
                            longitude = loc.getLongitude();
                        }
                    }*/

                }


            } 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 is not Enabled!");

            alertDialog.setMessage("Do you want 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 stopListener() {
            if (locationManager != null) {

                if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                    // TODO: Consider calling
                    //    ActivityCompat#requestPermissions
                    // here to request the missing permissions, and then overriding
                    //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
                    //                                          int[] grantResults)
                    // to handle the case where the user grants the permission. See the documentation
                    // for ActivityCompat#requestPermissions for more details.
                    return;
                }
                locationManager.removeUpdates(LocationTrack.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) {

        }
    }

Use the location tracker service in Activity like below

    locationTrack = new LocationTrack(MainActivity.this);


                    if (locationTrack.canGetLocation()) {


                        double longitude = locationTrack.getLongitude();
                        double latitude = locationTrack.getLatitude();

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

                        locationTrack.showSettingsAlert();
                    }

Refer this link which explained this.