FusedLocationApi.getLastLocation всегда имеет значение null, даже onCreated ()

2 Reson для этого

1. getLastLocation () не всегда указывает местоположение. Вы также должны написать обновление местоположения
2. На некоторых устройствах иногда сервис Google Play не подключается

Поэтому, чтобы избежать этого, вам нужно также получить местоположение из GPS, рассмотрите следующий код

добавьте эти зависимости в свой градиент сборки

compile 'com.google.android.gms:play-services-location:10.2.1'
compile 'cn.pedant.sweetalert:library:1.3'

Добавьте этот класс для получения местоположения - LocationResolver.java

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.IntentSender;
import android.content.pm.PackageManager;
import android.location.Location;
import android.location.LocationManager;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.provider.Settings;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.text.TextUtils;
import android.util.Log;
import android.widget.Toast;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.location.LocationSettingsRequest;


import cn.pedant.SweetAlert.SweetAlertDialog;

import static android.content.Context.LOCATION_SERVICE;



public class LocationResolver implements GoogleApiClient.ConnectionCallbacks,
        GoogleApiClient.OnConnectionFailedListener, LocationListener, android.location.LocationListener {

    // The minimum distance to change Updates in meters
    private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // 10 meters
    // The minimum time between updates in milliseconds
    private static final long MIN_TIME_BW_UPDATES = 1000 * 60 ; // 1 minute

    //Location Request code
    private final int REQUEST_LOCATION = 2;
    //Google Api Client
    private GoogleApiClient mGoogleApiClient;

    //Location request for google fused location Api
    private LocationRequest mLocationRequest;

    //Location manager for location services
    private LocationManager mLocationManager;

    private OnLocationResolved mOnLocationResolved;

    private Activity mActivity;

    //Location permission Dialog
    private SweetAlertDialog mDialog;

    public LocationResolver(Activity activity){
        mActivity=activity;
        buildGoogleApiClient();
        mLocationManager = (LocationManager) activity.getSystemService(LOCATION_SERVICE);
        createLocationRequest();
    }

    public void resolveLocation(Activity activity, OnLocationResolved onLocationResolved){
        this.mOnLocationResolved = onLocationResolved;
        this.mActivity=activity;

        if (isEveryThingEnabled()){
            startLocationPooling();
        }
    }

    public interface OnLocationResolved{
        void onLocationResolved(Location location);
    }


    /*
  * Checking every criteria are enabled for getting location from device
  * */
    public boolean isEveryThingEnabled() {
        if (!isLocationPermissionEnabled()) {
            showPermissionRequestDialog();
            return false;
        } else if (!isLocationEnabled(mActivity)) {
            showLocationSettingsDialog();
            return false;
        } else if (!isConnected()) {
            showWifiSettingsDialog(mActivity);
            return false;
        }

        return true;
    }


    /*
   * This function checks if location permissions are granted or not
   * */
    public boolean isLocationPermissionEnabled() {

        return !(Build.VERSION.SDK_INT >= 23 &&
                ContextCompat.checkSelfPermission(mActivity, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
                ContextCompat.checkSelfPermission(mActivity, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED);
    }


    /*
    * Previous location permissions were denied , this function opens app settings page
    * So user can enable permission manually
    * */
    private void startAppDetailsActivity() {

        final Intent i = new Intent();
        i.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
        i.addCategory(Intent.CATEGORY_DEFAULT);
        i.setData(Uri.parse("package:" + mActivity.getPackageName()));

        mActivity.startActivity(i);
    }



    private void showLocationSettingsDialog() {
        SweetAlertDialog builder = new SweetAlertDialog(mActivity, SweetAlertDialog.WARNING_TYPE);
        builder.setTitleText("Need Location");
        builder.setContentText("In order for the app to work seamlessly.Please  enable Location Service.");
        builder.setConfirmText("Enable");
        builder.setConfirmClickListener(new SweetAlertDialog.OnSweetClickListener() {
            @Override
            public void onClick(SweetAlertDialog dialog) {
                dialog.cancel();
                startLocationSettings();
            }
        });
        builder.setCancelText("Cancel");
        builder.setCancelClickListener(new SweetAlertDialog.OnSweetClickListener() {
            @Override
            public void onClick(SweetAlertDialog dialog) {
                dialog.cancel();

            }
        });

        builder.show();
    }

    private void startLocationSettings() {
        mActivity.startActivity(new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS));
    }

    /*
    * location permissions were denied with "do not show"  unchecked.. this function shows a dialog describing why this app
    * need location permission.
    * */
    private void showPermissionRequestDialog() {
        if (mDialog != null)
            mDialog.cancel();
        mDialog = new SweetAlertDialog(mActivity, SweetAlertDialog.NORMAL_TYPE);
        mDialog.setTitleText("You need location permission");
        mDialog.setContentText("Enable location permission");
        mDialog.setConfirmText("grant");
        mDialog.setConfirmClickListener(new SweetAlertDialog.OnSweetClickListener() {
            @Override
            public void onClick(SweetAlertDialog dialog) {
                dialog.cancel();
                ActivityCompat.requestPermissions(mActivity,
                        new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
                        REQUEST_LOCATION);
            }
        });
        mDialog.setCancelText("Cancel");
        mDialog.setCancelClickListener(new SweetAlertDialog.OnSweetClickListener() {
            @Override
            public void onClick(SweetAlertDialog dialog) {
                dialog.cancel();
            }
        });
        mDialog.show();
    }

    /*
    *
    *
    *  Previously Permission Request was cancelled with 'Dont Ask Again',
    *  Redirect to Settings after showing Information about why you need the permission
    *
    * */
    private void showPermissionDeniedDialog() {

        if (mDialog != null)
            mDialog.cancel();
        mDialog = new SweetAlertDialog(mActivity, SweetAlertDialog.NORMAL_TYPE);
        mDialog.setTitleText("Need Location Permission");


        mDialog.setContentText("Enable location permission");
        mDialog.setConfirmText("grant");
        mDialog.setConfirmClickListener(new SweetAlertDialog.OnSweetClickListener() {
            @Override
            public void onClick(SweetAlertDialog dialog) {
                dialog.cancel();
                startAppDetailsActivity();
            }
        });
        mDialog.setCancelText("Cancel");
        mDialog.setCancelClickListener(new SweetAlertDialog.OnSweetClickListener() {
            @Override
            public void onClick(SweetAlertDialog dialog) {
                dialog.cancel();

            }
        });

        mDialog.show();
    }


    public void onRequestPermissionsResult(int requestCode,
                                           String permissions[], int[] grantResults) {
        switch (requestCode) {
            case REQUEST_LOCATION: {
                // If request is cancelled, the result arrays are empty.
                if (grantResults.length > 0
                        && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    startLocationPooling();
                } else {
                    if (ActivityCompat.shouldShowRequestPermissionRationale(mActivity,
                            Manifest.permission.ACCESS_FINE_LOCATION) && ActivityCompat.shouldShowRequestPermissionRationale(mActivity,
                            Manifest.permission.ACCESS_COARSE_LOCATION)) {
                        showPermissionRequestDialog();

                    } else {
                        showPermissionDeniedDialog();

                    }
                }
            }
        }


    }

    /*
    * Starting location pooling
    * */
    public void startLocationPooling() {


        if (ActivityCompat.checkSelfPermission(mActivity, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(mActivity, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            //
            //    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;

        }
        Location location = LocationServices.FusedLocationApi.getLastLocation(
                mGoogleApiClient);
        if (location != null) {
            mOnLocationResolved.onLocationResolved(location);
        } else {
            if (mGoogleApiClient.isConnected())//if googleClient can get location from device the go for location update
                startLocationUpdates();
            else getLocation(); //Google Client cannot connected to its server. so we are fetching location directly from device
        }

    }

    private synchronized void buildGoogleApiClient() {
        mGoogleApiClient = new GoogleApiClient.Builder(mActivity)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
    }



    public void onDestroy() {

        mGoogleApiClient.disconnect();
    }

    public void onStop() {
        if (mDialog != null) {
            mDialog.cancel();
        }
        stopLocationUpdates();
        mGoogleApiClient.disconnect();
    }

    public void onStart() {

        mGoogleApiClient.connect();
    }

    @Override
    public void onConnected(Bundle bundle) {

        // startLocationPooling();

    }

    /*
   * checks whether the device connected or not*/
    public boolean isConnected() {
        try {
            ConnectivityManager cm = (ConnectivityManager) mActivity.getSystemService(Context.CONNECTIVITY_SERVICE);
            NetworkInfo netInfo = cm.getActiveNetworkInfo();

            return netInfo != null && netInfo.isConnected();
        } catch (Exception e) {
            return false;
        }
    }

    @Override
    public void onConnectionSuspended(int i) {

        mGoogleApiClient.connect();
    }

    @Override
    public void onLocationChanged(Location location) {
        if (location != null) {
           mOnLocationResolved.onLocationResolved(location);
            stopLocationUpdates();
        }

    }

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

    @Override
    public void onProviderEnabled(String s) {
    }

    @Override
    public void onProviderDisabled(String s) {

    }



    @Override
    public void onConnectionFailed(ConnectionResult connectionResult) {
        if (connectionResult.hasResolution()) {
            try {
                // Start an Activity that tries to resolve the error
                connectionResult.startResolutionForResult(mActivity, ConnectionResult.RESOLUTION_REQUIRED);
            } catch (IntentSender.SendIntentException e) {
                e.printStackTrace();
            }
        } else {
            Log.e("TAG", "Location services connection failed with code==>" + connectionResult.getErrorCode());
            Log.e("TAG", "Location services connection failed Because of==> " + connectionResult.getErrorMessage());
        }

    }

    private void createLocationRequest() {
        Log.i("TAG", "CreateLocationRequest");
        mLocationRequest = new LocationRequest();
        long UPDATE_INTERVAL = 10 * 1000;
        mLocationRequest.setInterval(UPDATE_INTERVAL);
        long FASTEST_INTERVAL = 10000;
        mLocationRequest.setFastestInterval(FASTEST_INTERVAL);
        mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
        LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder()
                .addLocationRequest(mLocationRequest);
        //**************************
        builder.setAlwaysShow(true); //this is the key ingredient
        //**************************

    }

    private void startLocationUpdates() {

        Log.i("TAG", "StartLocationUpdates");

        if (Build.VERSION.SDK_INT >= 23) {
            if (ContextCompat.checkSelfPermission(mActivity, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED && ContextCompat.checkSelfPermission(mActivity, Manifest.permission.ACCESS_COARSE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
                // TODO: Consider calling
                LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient,
                        mLocationRequest, this);

            }
        } else {
            LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient,
                    mLocationRequest, this);
        }

    }

    private void stopLocationUpdates() {

        try {
            if (mGoogleApiClient.isConnected())
                LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);

            if (mLocationManager != null) {
                mLocationManager.removeUpdates(this);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }


    public void getLocation() {
        try {


            // getting GPS status
            Boolean isGPSEnabled = mLocationManager
                    .isProviderEnabled(LocationManager.GPS_PROVIDER);

            // getting network status
            Boolean isNetworkEnabled = mLocationManager
                    .isProviderEnabled(LocationManager.NETWORK_PROVIDER);

            if (!isGPSEnabled && !isNetworkEnabled) {
                Log.e("Location", "No provider enabled");
            } else {
                if (ActivityCompat.checkSelfPermission(mActivity, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(mActivity, 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;
                }
                Location location = null;
                // First get location from Network Provider
                if (isNetworkEnabled) {
                    if (mLocationManager != null) {
                        location = mLocationManager
                                .getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
                        if (location != null) {
                           mOnLocationResolved.onLocationResolved(location);
                        } else {
                            mLocationManager.requestLocationUpdates(
                                    LocationManager.NETWORK_PROVIDER,
                                    MIN_TIME_BW_UPDATES,
                                    MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                            Log.d("Network", "Network");
                        }
                    }
                }
                // if GPS Enabled get lat/long using GPS Services
                if (isGPSEnabled) {
                    if (location == null) {
                        if (mLocationManager != null) {
                            location = mLocationManager
                                    .getLastKnownLocation(LocationManager.GPS_PROVIDER);
                            if (location != null) {
                                mOnLocationResolved.onLocationResolved(location);
                            } else {
                                mLocationManager.requestLocationUpdates(
                                        LocationManager.GPS_PROVIDER,
                                        MIN_TIME_BW_UPDATES,
                                        MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                                Log.d("GPS Enabled", "GPS Enabled");
                            }
                        }
                    }
                }
            }

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


    }


    /*
   * checks whether the device connected or not*/
    public static boolean isNetWorkConnected(Context  context) {
        try {
            ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
            NetworkInfo netInfo = cm.getActiveNetworkInfo();

            return netInfo != null && netInfo.isConnected();
        } catch (Exception e) {
            return false;
        }
    }


    public   void showWifiSettingsDialog(final Context  context) {
        SweetAlertDialog builder = new SweetAlertDialog(context, SweetAlertDialog.WARNING_TYPE);
        builder.setTitleText("Need Internet");
        builder.setContentText("Please enable your internet connection");

        builder.setConfirmText("Enable");
        builder.setConfirmClickListener(new SweetAlertDialog.OnSweetClickListener() {
            @Override
            public void onClick(SweetAlertDialog dialog) {
                dialog.cancel();
                startWifiSettings(context);
            }
        });
        builder.setCancelText("Cancel");
        builder.setCancelClickListener(new SweetAlertDialog.OnSweetClickListener() {
            @Override
            public void onClick(SweetAlertDialog dialog) {
                dialog.cancel();

            }
        });

        builder.show();

    }

    private   void startWifiSettings(Context context) {
        try {
            context.startActivity(new Intent(Settings.ACTION_WIFI_SETTINGS));
        } catch (Exception e) {
            Toast.makeText(context, "Something went wrong", Toast.LENGTH_SHORT).show();
        }
    }

    public static boolean isLocationEnabled(Context context) {
        int locationMode = 0;
        String locationProviders;

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
            try {
                locationMode = Settings.Secure.getInt(context.getContentResolver(), Settings.Secure.LOCATION_MODE);

            } catch (Settings.SettingNotFoundException e) {
                e.printStackTrace();
                return false;
            }

            return locationMode != Settings.Secure.LOCATION_MODE_OFF;

        } else {
            locationProviders = Settings.Secure.getString(context.getContentResolver(), Settings.Secure.LOCATION_PROVIDERS_ALLOWED);
            return !TextUtils.isEmpty(locationProviders);
        }
    }


}

В своей деятельности следуйте этим шагам

Создать и инициализировать переменную LocationResolver

  private LocationResolver mLocationResolver;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
mLocationResolver=new LocationResolver(this);

}

А также добавьте эти строки в свою деятельность

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

@Override
protected void onStop() {
    super.onStop();
    mLocationResolver.onStop();
}

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

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    mLocationResolver.onRequestPermissionsResult(requestCode, permissions, grantResults);
}

Использование: когда вам нужно местоположение, используйте этот код для определения местоположения

    void retrieveLocation() {

 mLocationResolver.resolveLocation(this, new LocationResolver.OnLocationResolved() {
            @Override
            public void onLocationResolved(Location location) {
                // Do what ever you want
            }
        });
    }