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Can not get accurate location while travelling in bus without internet

I am developing offline car tracker android application. It will update location after 5 min and stores it in SQLite.I used FusedLocationAPI but can not get accurate location while travelling in bus without Internet. I am getting accuracy 999m and getting same location after every 5 minutes.
I set alarm manager to 5 minutes.
public static void startAlarmManager(Context context)
{
preferences =context.getSharedPreferences(Constant.SHARED_PREF_NAME, Context.MODE_PRIVATE);
int duration= Integer.parseInt(preferences.getString(Constant.DURATION_SHARED_PREF,Constant.CONSTANT_DURATION_SHARED_PREF));
Log.d("duration",duration+"");
alarmManager = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
gpsTrackerIntent = new Intent(context, GpsTrackerAlarmReceiver.class);
pendingIntent = PendingIntent.getBroadcast(context, 0, gpsTrackerIntent, 0);
alarmManager.setRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP,
SystemClock.elapsedRealtime(),
5*60000,
pendingIntent);
}
It will fire broadcast receiver.
public class GpsTrackerAlarmReceiver extends WakefulBroadcastReceiver {
private static final String TAG = "GpsTrackerAlarmReceiver";
#Override
public void onReceive(Context context, Intent intent) {
LocationManager manager = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE );
boolean statusOfGPS = manager.isProviderEnabled(LocationManager.GPS_PROVIDER);
if(statusOfGPS) {
context.startService(new Intent(context, LocationService.class));
}
}
}
This is location service. I am getting location with this way.
public class LocationService extends Service implements
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
private static final String TAG = "LocationService";
public static GoogleApiClient googleApiClient;
private LocationRequest locationRequest;
public Context context;
private DatabaseHelper db;
private boolean currentlyProcessingLocation = false;
#Override
public void onCreate() {
super.onCreate();
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.d(TAG, "onStartCommand");
if (!currentlyProcessingLocation) {
currentlyProcessingLocation = true;
startTracking();
}
return START_NOT_STICKY;
}
private void startTracking() {
if (GooglePlayServicesUtil.isGooglePlayServicesAvailable(this) == ConnectionResult.SUCCESS) {
googleApiClient = new GoogleApiClient.Builder(this)
.addApi(LocationServices.API)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.build();
if (!googleApiClient.isConnected() || !googleApiClient.isConnecting()) {
googleApiClient.connect();
}
} else {
Log.e(TAG, "unable to connect to google play services.");
}
}
#Override
public void onConnected(#Nullable Bundle bundle) {
Log.d(TAG, "onConnected");
locationRequest = LocationRequest.create();
locationRequest.setInterval(1000); // milliseconds
locationRequest.setFastestInterval(1000); // the fastest rate in milliseconds at which your app can handle location updates
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
LocationServices.FusedLocationApi.requestLocationUpdates(
googleApiClient, locationRequest, this);
}
#Override
public void onConnectionSuspended(int i) {
Log.e(TAG, "GoogleApiClient connection has been suspend");
}
#Override
public void onLocationChanged(Location location) {
Log.d(TAG, "onLocationChanged");
startupdate(location);
}
private void startupdate(Location location) {
if (location != null) {
db=new DatabaseHelper(this);
db.insertLocation(location.getLatitude(), location.getLongitude(), "FusedApi Provider", location.getAccuracy());
stopLocationUpdates();
stopSelf();
}
}
public void stopLocationUpdates() {
if (googleApiClient != null && googleApiClient.isConnected()) {
googleApiClient.disconnect();
}
}
#Override
public void onConnectionFailed(#NonNull ConnectionResult connectionResult) {
Log.e(TAG, "onConnectionFailed");
stopLocationUpdates();
stopSelf();
}
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
}
Please help...if i am wrong. Thanks in advance.

When GPS is not practical you can use LocationManager.NETWORK_PROVIDER, this is location from the phone carrier that is less accurate than GPS but is available everywhere the carrier has a tower. The way I do it is a set a flag isGpsAvailable() to see if that is true I use GPS otherwise I use network provided location. This Google's doc provides detailed solutions including code snippets that you can use and change the way you it fits your needs.

Recieved runtime permission for ACCESS_FINE_LOCATION, but still getting SecurityException

The flow goes like this. I get permission for Location(FINE and COARSE). OnPermissionGrantResult:
public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
switch (requestCode) {
case LOCATION:
if(grantResults[0] == 0){
(new AsyncTask<Void, Void, Void>(){
#Override protected Void doInBackground(Void... params){
getAndSetLocation();
}
}).execute();
}
break;
}
}
}
public void getAndSetLocation(){
startGPSService();
//GPS Tracker is the GPS Service
while(GPSTracker.location==null) {
try {
synchronized (lock) {
lock.wait();
}
} catch (InterruptedException e) {
Log.e(TAG, "getLocation: "+e.getLocalizedMessage() );
}
}
location = new Location(GPSTracker.location);
stopGPSService();
}
GPSTracker service
public class GPSTracker extends android.app.Service implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, com.google.android.gms.location.LocationListener {
private LocationRequest mLocationRequest;
private GoogleApiClient mGoogleApiClient;
private static final String TAG = GPSTracker.class.getSimpleName();
public static Location location;
#Override
public void onCreate() {
super.onCreate();
buildGoogleApiClient();
Log.i(TAG, "onCreate");
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.i(TAG, "onStartCommand");
if (!mGoogleApiClient.isConnected())
mGoogleApiClient.connect();
return START_STICKY;
}
#Override
public void onConnected(Bundle bundle) {
Log.i(TAG, "onConnected" + bundle);
Location l;
try {
l = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
}catch (SecurityException e){ //Error here
l = null;
}
if (l != null) {
Log.i(TAG, "lat " + l.getLatitude());
Log.i(TAG, "lng " + l.getLongitude());
location = l;
synchronized (lock) {
lock.notify();
}
}
startLocationUpdate();
}
#Override
public void onConnectionSuspended(int i) {
Log.i(TAG, "onConnectionSuspended " + i);
}
#Override
public void onLocationChanged(Location location) {
Log.i(TAG, "lat " + location.getLatitude());
Log.i(TAG, "lng " + location.getLongitude());
GPSTracker.location = location;
lock.notify();
}
#Override
public void onDestroy() {
super.onDestroy();
}
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public void onConnectionFailed(#NonNull ConnectionResult connectionResult) {
Log.i(TAG, "onConnectionFailed ");
}
private void initLocationRequest() {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(5000);
mLocationRequest.setFastestInterval(2000);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
}
private void startLocationUpdate() {
initLocationRequest();
try {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}catch (SecurityException e){
Log.e(TAG, "startLocationUpdate: ", e);
}
}
private void stopLocationUpdate() {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
}
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addOnConnectionFailedListener(this)
.addConnectionCallbacks(this)
.addApi(LocationServices.API)
.build();
}
}
Error is being thrown at onConnected even though, permission was received. Is it because the service is still not aware of the received permission or is it the way it is being executed? Or is the async task, the issue? It works fine from the second time on, but the first time, it always throws a security exception.
Exception Trace:
java.lang.SecurityException: Client must have ACCESS_FINE_LOCATION permission to request PRIORITY_HIGH_ACCURACY locations.
Code which requests permission:
public static boolean checkForPermissions(Activity context, String[] permissions, final int requestCode) {
if (permissions == null) return true;
boolean resultFlag = true;
final List<String> requiredPermissions = new ArrayList<>();
if (Build.VERSION.SDK_INT >= 23){
for (String permission : permissions) {
if (context.checkCallingOrSelfPermission(permission) != PackageManager.PERMISSION_GRANTED) {
requiredPermissions.add(permission);
resultFlag = false;
}
}
}
// Request all permissions at once..
if(requiredPermissions.size()!=0) {
requestPermissions(context, requiredPermissions.toArray(new String[0]), requestCode);
}
return resultFlag;
}
checkForPermissions(mContext, new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION}, LOCATION);

I think you need ACCESS_COARSE_LOCATION too.
reference

You forgot to connect to GoogleApiClient in GPSTracker
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addOnConnectionFailedListener(this)
.addConnectionCallbacks(this)
.addApi(LocationServices.API)
.build();
mGoogleApiClient.connect();
}
This will do.

last location is retrieved from location cache, now if you are starting app for first time there may not be any last location saved. in which case this line
l = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
returns null. now this only happens for first time because after that your app starts requesting updates and last location is no longer null.

Get LastKnownLocation in Android returns null

I am trying to fetch lastknown location but it is giving me null value. I tested whether GPS is enabled or not, it's returning true.
Even I went into Google Maps and pointed my location (thinking that location data might be cleared) but it still didn't work.
Here is my Code
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
boolean isgps=locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
Log.v("is GPs Enabled",isgps+"");
Location location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
updateNewLocation(location);
}
private void updateNewLocation(Location location) {
TextView myLocationText=(TextView)findViewById(R.id.myLocation);
if(location!=null){
double lat=location.getLatitude();
double lng=location.getLongitude();
myLocationText.setText("lat:"+lat+"\nlong:"+lng);
Log.v("Location","lat:"+lat+"\nlong:"+lng);
}
}

hi why trying to use getLastKnownLocation.It return your previous latitude and longitude.Most probably it retrun you null.It takes time to update and it return previous lat lng.It could be very old or new old.Its not accurate and correct. So,Its better you go for new approach.
I'm just referring you google Fused api for location any kind of updation or current.Its very accurate.
How you can fused api in your project.See i'll give you small example.
Step 1. Make this class GoogleLocationService.java
public class GoogleLocationService {
private GoogleServicesCallbacks callbacks = new GoogleServicesCallbacks();
LocationUpdateListener locationUpdateListener;
Context activity;
protected GoogleApiClient mGoogleApiClient;
protected LocationRequest mLocationRequest;
public static final long UPDATE_INTERVAL_IN_MILLISECONDS = 30000;
public GoogleLocationService(Context activity, LocationUpdateListener locationUpdateListener) {
this.locationUpdateListener = locationUpdateListener;
this.activity = activity;
buildGoogleApiClient();
}
protected synchronized void buildGoogleApiClient() {
//Log.i(TAG, "Building GoogleApiClient");
mGoogleApiClient = new GoogleApiClient.Builder(activity)
.addConnectionCallbacks(callbacks)
.addOnConnectionFailedListener(callbacks)
.addApi(LocationServices.API)
.build();
createLocationRequest();
mGoogleApiClient.connect();
}
protected void createLocationRequest() {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(UPDATE_INTERVAL_IN_MILLISECONDS);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
}
private class GoogleServicesCallbacks implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {
#Override
public void onConnected(Bundle bundle) {
startLocationUpdates();
}
#Override
public void onConnectionSuspended(int i) {
mGoogleApiClient.connect();
}
#Override
public void onConnectionFailed(#NonNull ConnectionResult connectionResult) {
if (connectionResult.getErrorCode() == ConnectionResult.SERVICE_VERSION_UPDATE_REQUIRED) {
Toast.makeText(activity, "Google play service not updated", Toast.LENGTH_LONG).show();
}
locationUpdateListener.cannotReceiveLocationUpdates();
}
#Override
public void onLocationChanged(Location location) {
if (location.hasAccuracy()) {
if (location.getAccuracy() < 30) {
locationUpdateListener.updateLocation(location);
}
}
}
}
private static boolean locationEnabled(Context context) {
boolean gps_enabled = false;
LocationManager lm = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
try {
gps_enabled = lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
} catch (Exception ex) {
ex.printStackTrace();
}
return gps_enabled;
}
private boolean servicesConnected(Context context) {
return isPackageInstalled(GooglePlayServicesUtil.GOOGLE_PLAY_STORE_PACKAGE, context);
}
private boolean isPackageInstalled(String packagename, Context context) {
PackageManager pm = context.getPackageManager();
try {
pm.getPackageInfo(packagename, PackageManager.GET_ACTIVITIES);
return true;
} catch (PackageManager.NameNotFoundException e) {
e.printStackTrace();
return false;
}
}
public void startUpdates() {
/*
* Connect the client. Don't re-start any requests here; instead, wait
* for onResume()
*/
if (servicesConnected(activity)) {
if (locationEnabled(activity)) {
locationUpdateListener.canReceiveLocationUpdates();
startLocationUpdates();
} else {
locationUpdateListener.cannotReceiveLocationUpdates();
Toast.makeText(activity, "Unable to get your location.Please turn on your device Gps", Toast.LENGTH_LONG).show();
}
} else {
locationUpdateListener.cannotReceiveLocationUpdates();
Toast.makeText(activity, "Google play service not available", Toast.LENGTH_LONG).show();
}
}
//stop location updates
public void stopUpdates() {
stopLocationUpdates();
}
//start location updates
private void startLocationUpdates() {
if (checkSelfPermission(activity, ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && checkSelfPermission(activity, ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
if (mGoogleApiClient.isConnected()) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, callbacks);
}
}
public void stopLocationUpdates() {
if (mGoogleApiClient.isConnected()) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, callbacks);
}
}
public void startGoogleApi() {
mGoogleApiClient.connect();
}
public void closeGoogleApi() {
mGoogleApiClient.disconnect();
}
}
Step2. Make this interface
LocationUpdateListener.java
public interface LocationUpdateListener {
/**
* Called immediately the service starts if the service can obtain location
*/
void canReceiveLocationUpdates();
/**
* Called immediately the service tries to start if it cannot obtain location - eg the user has disabled wireless and
*/
void cannotReceiveLocationUpdates();
/**
* Called whenever the location has changed (at least non-trivially)
* #param location
*/
void updateLocation(Location location);
/**
* Called when GoogleLocationServices detects that the device has moved to a new location.
* #param localityName The name of the locality (somewhere below street but above area).
*/
void updateLocationName(String localityName, Location location);
}
Step 3. Use this piece of code where you want to get location
private GoogleLocationService googleLocationService;
googleLocationService = new GoogleLocationService(context, new LocationUpdateListener() {
#Override
public void canReceiveLocationUpdates() {
}
#Override
public void cannotReceiveLocationUpdates() {
}
//update location to our servers for tracking purpose
#Override
public void updateLocation(Location location) {
if (location != null ) {
Timber.e("updated location %1$s %2$s", location.getLatitude(), location.getLongitude());
}
}
#Override
public void updateLocationName(String localityName, Location location) {
googleLocationService.stopLocationUpdates();
}
});
googleLocationService.startUpdates();
and call this onDestroy
if (googleLocationService != null) {
googleLocationService.stopLocationUpdates();
}
Thanks hope this help you.

Send GPS coordinates periodically

I am a windows application programmer and recently started learning android. I am planning to make an app that will send GPS coordinates periodically say after every 30 seconds after clicking "start" button and stop doing so by clicking "stop" button (I have already developed a web service accepting the data) . In windows I would use a timer and on every "tick" will find the GPS coordinates and send it. Please help in understanding how a similar thing can be done in android.

Please check how i'm using in my app and its working perfect.I'm using fused api for update location please follow few steps.
Step 1. Make this class
GoogleLocationService.java
public class GoogleLocationService {
private GoogleServicesCallbacks callbacks = new GoogleServicesCallbacks();
LocationUpdateListener locationUpdateListener;
Context activity;
protected GoogleApiClient mGoogleApiClient;
protected LocationRequest mLocationRequest;
public static final long UPDATE_INTERVAL_IN_MILLISECONDS = 30000;
public GoogleLocationService(Context activity, LocationUpdateListener locationUpdateListener) {
this.locationUpdateListener = locationUpdateListener;
this.activity = activity;
buildGoogleApiClient();
}
protected synchronized void buildGoogleApiClient() {
//Log.i(TAG, "Building GoogleApiClient");
mGoogleApiClient = new GoogleApiClient.Builder(activity)
.addConnectionCallbacks(callbacks)
.addOnConnectionFailedListener(callbacks)
.addApi(LocationServices.API)
.build();
createLocationRequest();
mGoogleApiClient.connect();
}
protected void createLocationRequest() {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(UPDATE_INTERVAL_IN_MILLISECONDS);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
}
private class GoogleServicesCallbacks implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {
#Override
public void onConnected(Bundle bundle) {
startLocationUpdates();
}
#Override
public void onConnectionSuspended(int i) {
mGoogleApiClient.connect();
}
#Override
public void onConnectionFailed(#NonNull ConnectionResult connectionResult) {
if (connectionResult.getErrorCode() == ConnectionResult.SERVICE_VERSION_UPDATE_REQUIRED) {
Toast.makeText(activity, "Google play service not updated", Toast.LENGTH_LONG).show();
}
locationUpdateListener.cannotReceiveLocationUpdates();
}
#Override
public void onLocationChanged(Location location) {
if (location.hasAccuracy()) {
if (location.getAccuracy() < 30) {
locationUpdateListener.updateLocation(location);
}
}
}
}
private static boolean locationEnabled(Context context) {
boolean gps_enabled = false;
LocationManager lm = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
try {
gps_enabled = lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
} catch (Exception ex) {
ex.printStackTrace();
}
return gps_enabled;
}
private boolean servicesConnected(Context context) {
return isPackageInstalled(GooglePlayServicesUtil.GOOGLE_PLAY_STORE_PACKAGE, context);
}
private boolean isPackageInstalled(String packagename, Context context) {
PackageManager pm = context.getPackageManager();
try {
pm.getPackageInfo(packagename, PackageManager.GET_ACTIVITIES);
return true;
} catch (PackageManager.NameNotFoundException e) {
e.printStackTrace();
return false;
}
}
public void startUpdates() {
/*
* Connect the client. Don't re-start any requests here; instead, wait
* for onResume()
*/
if (servicesConnected(activity)) {
if (locationEnabled(activity)) {
locationUpdateListener.canReceiveLocationUpdates();
startLocationUpdates();
} else {
locationUpdateListener.cannotReceiveLocationUpdates();
Toast.makeText(activity, "Unable to get your location.Please turn on your device Gps", Toast.LENGTH_LONG).show();
}
} else {
locationUpdateListener.cannotReceiveLocationUpdates();
Toast.makeText(activity, "Google play service not available", Toast.LENGTH_LONG).show();
}
}
//stop location updates
public void stopUpdates() {
stopLocationUpdates();
}
//start location updates
private void startLocationUpdates() {
if (checkSelfPermission(activity, ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && checkSelfPermission(activity, ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
if (mGoogleApiClient.isConnected()) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, callbacks);
}
}
public void stopLocationUpdates() {
if (mGoogleApiClient.isConnected()) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, callbacks);
}
}
public void startGoogleApi() {
mGoogleApiClient.connect();
}
public void closeGoogleApi() {
mGoogleApiClient.disconnect();
}
}
Step2. Make this interface
LocationUpdateListener.java
public interface LocationUpdateListener {
/**
* Called immediately the service starts if the service can obtain location
*/
void canReceiveLocationUpdates();
/**
* Called immediately the service tries to start if it cannot obtain location - eg the user has disabled wireless and
*/
void cannotReceiveLocationUpdates();
/**
* Called whenever the location has changed (at least non-trivially)
* #param location
*/
void updateLocation(Location location);
/**
* Called when GoogleLocationServices detects that the device has moved to a new location.
* #param localityName The name of the locality (somewhere below street but above area).
*/
void updateLocationName(String localityName, Location location);
}
Step 3. Call this on your oncreate
private GoogleLocationService googleLocationService;
googleLocationService = new GoogleLocationService(context, new LocationUpdateListener() {
#Override
public void canReceiveLocationUpdates() {
}
#Override
public void cannotReceiveLocationUpdates() {
}
//update location to our servers for tracking purpose
#Override
public void updateLocation(Location location) {
if (location != null ) {
Timber.e("updated location %1$s %2$s", location.getLatitude(), location.getLongitude());
}
}
#Override
public void updateLocationName(String localityName, Location location) {
googleLocationService.stopLocationUpdates();
}
});
googleLocationService.startUpdates();
and call this onDestroy
if (googleLocationService != null) {
googleLocationService.stopLocationUpdates();
}
Hope this will help you to solve your problem.

Take a look to RxGpsService (An Android service to retrieve GPS locations and route stats using RxJava). It retrieves a RouteStats object which contains the current speed, distance, time elapsed and waypoints. Also you can play/stop the chrono in order to discard locations when chrono is stopped.

How to get Current Location using seperate class in Android

I need to get current location using seperate class which not in the Activity. This is my code and it doesnt't work. Anyone have idea to fix this.This application is always crash when I try to get location details.
package com.example.ishanfx.departmentapp.network;
import android.content.Context;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
public class LocationHandler implements LocationListener,GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener {
private LocationManager locationManager;
Location mLastLocation;
LocationRequest mLocationRequest;
private String latitude;
private String longitude;
Context context;
private static GoogleApiClient mGoogleApiClient;
public LocationHandler(Context context) {
this.context = context;
locationManager = (LocationManager) context
.getSystemService(Context.LOCATION_SERVICE);
buildGoogleApiClient();
}
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(context)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mGoogleApiClient.connect();
}
private void setMostRecentLocation(Location lastKnownLocation) {
}
public String getLatitude() {
return latitude;
}
public String getLongitude() {
return longitude;
}
#Override
public void onLocationChanged(Location location) {
double lon = (double) (location.getLongitude());
double lat = (double) (location.getLatitude());
latitude = lat + "";
longitude = lon + "";
}
/*
* (non-Javadoc)
*
* #see
* android.location.LocationListener#onProviderDisabled(java.lang.String)
*/
#Override
public void onProviderDisabled(String arg0) {
// TODO Auto-generated method stub
}
/*
* (non-Javadoc)
*
* #see
* android.location.LocationListener#onProviderEnabled(java.lang.String)
*/
#Override
public void onProviderEnabled(String arg0) {
// TODO Auto-generated method stub
}
#Override
public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
// TODO Auto-generated method stub
}
#Override
public void onConnected(Bundle bundle) {
mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
mGoogleApiClient);
if (mLastLocation != null) {
latitude =String.valueOf(mLastLocation.getLatitude());
longitude = String.valueOf(mLastLocation.getLongitude());
}
}
#Override
public void onConnectionSuspended(int i) {
}
#Override
public void onConnectionFailed(ConnectionResult connectionResult) {
}
}
This is the mainActivity.When I call this application will crash.
LocationHandler appLocationManager = new LocationHandler(HomeActivity.this);
Toast.makeText(getApplicationContext(), appLocationManager.getLatitude().toString(), Toast.LENGTH_SHORT).show();
Toast.makeText(getApplicationContext(), appLocationManager.getLongitude().toString(), Toast.LENGTH_SHORT).show();
This is the Log
FATAL EXCEPTION: main
java.lang.NullPointerException
at com.example.ishanfx.departmentapp.HomeActivity.onOptionsItemSelected(HomeActivity.java:172)
at android.app.Activity.onMenuItemSelected(Activity.java:2502)
at android.support.v4.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:361)
at android.support.v7.app.AppCompatActivity.onMenuItemSelected(AppCompatActivity.java:147)
at android.support.v7.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:100)
at android.support.v7.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:100)
at android.support.v7.app.ToolbarActionBar$2.onMenuItemClick(ToolbarActionBar.java:68)
at android.support.v7.widget.Toolbar$1.onMenuItemClick(Toolbar.java:172)
at android.support.v7.widget.ActionMenuView$MenuBuilderCallback.onMenuItemSelected(ActionMenuView.java:760)
at android.support.v7.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:811)
at android.support.v7.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:152)
at android.support.v7.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:958)
at android.support.v7.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:948)
at android.support.v7.view.menu.MenuPopupHelper.onItemClick(MenuPopupHelper.java:191)
at android.widget.AdapterView.performItemClick(AdapterView.java:292)
at android.widget.AbsListView.performItemClick(AbsListView.java:1065)
at android.widget.AbsListView$PerformClick.run(AbsListView.java:2522)
at android.widget.AbsListView$1.run(AbsListView.java:3183)
at android.os.Handler.handleCallback(Handler.java:605)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4441)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
at dalvik.system.NativeStart.main(Native Method)

I have updated above class in a clean way.
public class LocationHandler implements LocationListener,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener {
private Context mContext;
private GoogleApiClient mGoogleApiClient;
private LocationRequest mLocationRequest;
private OnLocationUpdateListener onLocationUpdateListener;
public LocationHandler(Context mContext) {
this.mContext = mContext;
buildGoogleApiClient();
createLocationRequest();
}
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(mContext)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mGoogleApiClient.connect();
}
public void startLocationUpdates(Context mContext) {
if (ActivityCompat.checkSelfPermission(mContext,
Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED
&& ActivityCompat.checkSelfPermission(mContext,
Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
LocationServices.FusedLocationApi.requestLocationUpdates(
mGoogleApiClient, mLocationRequest, this);
}
private void stopLocationUpdate(Context mContext) {
LocationServices.FusedLocationApi.removeLocationUpdates(
mGoogleApiClient, this);
}
//other new Methods but not using right now..
protected void createLocationRequest() {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(10000);//set the interval in which you want to get locations
mLocationRequest.setFastestInterval(5000);//if a location is available sooner you can get it (i.e. another app is using the location services)
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
}
#Override
public void onConnected(#Nullable Bundle bundle) {
startLocationUpdates(mContext);
}
#Override
public void onConnectionSuspended(int i) {
}
#Override
public void onConnectionFailed(#NonNull ConnectionResult connectionResult) {
}
#Override
public void onLocationChanged(Location location) {
if(mGoogleApiClient.isConnected() && onLocationUpdateListener != null){
onLocationUpdateListener.onLocationChange(location);
}
}
public void setOnLocationUpdateListener(OnLocationUpdateListener onLocationUpdateListener) {
this.onLocationUpdateListener = onLocationUpdateListener;
}
}
where OnLocationUpdateListener is
public interface OnLocationUpdateListener {
void onLocationChange(Location location);
void onError(EnumUtil.ErrorType errorType);
}

It takes a little time for the onConnected event to fire.
You need to give it a little time before making your toasts.
I'd add an isConnected property to your LocationHandler class like so:
private boolean isconnected = false;
public boolean isConnected() {
return isconnected;
}
#Override
public void onConnected(Bundle bundle) {
mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
mGoogleApiClient);
if (mLastLocation != null) {
latitude =String.valueOf(mLastLocation.getLatitude());
longitude = String.valueOf(mLastLocation.getLongitude());
}
this.isconnected = true;
}
Then in MainActivity
LocationHandler appLocationManager = new LocationHandler(HomeActivity.this);
while(!appLocationManager.isConnected()) {
// wait for a bit
}
if (appLocationManager.isConnected()) {
Toast.makeText(getApplicationContext(), appLocationManager.getLatitude().toString(), Toast.LENGTH_SHORT).show();
Toast.makeText(getApplicationContext(), appLocationManager.getLongitude().toString(), Toast.LENGTH_SHORT).show();
}

You have to set the value of latitude and longitude using setter and then get using getter.. since no value is getting set the getter is returning null value thus null pointer exception.

Here is another solution with FusedLocationProviderClient as FusedLocationApi is deprecated.
public class LocationHandler {
private Activity activity;
private FusedLocationProviderClient mFusedLocationProviderClient;
private Location mLastKnownLocation;
private LocationCallback mLocationCallback;
private LocationRequest mLocationRequest;
private OnLocationUpdateListener onLocationUpdateListener;
private boolean updateStartedInternally = false;
public LocationHandler(Activity activity, OnLocationUpdateListener onLocationUpdateListener) {
this.activity = activity;
this.onLocationUpdateListener = onLocationUpdateListener;
mFusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(activity);
createLocationRequest();
getDeviceLocation();
mLocationCallback = new LocationCallback() {
#Override
public void onLocationResult(LocationResult locationResult) {
List<Location> locationList = locationResult.getLocations();
if (locationList.size() > 0) {
//The last location in the list is the newest
Location location = locationList.get(locationList.size() - 1);
mLastKnownLocation = location;
if (onLocationUpdateListener != null) {
onLocationUpdateListener.onLocationChange(location);
if(updateStartedInternally){
stopLocationUpdate();
}
}
}
}
};
}
private void getDeviceLocation() {
/*
* Get the best and most recent location of the device, which may be null in rare
* cases when a location is not available.
*/
try {
Task locationResult = mFusedLocationProviderClient.getLastLocation();
locationResult.addOnCompleteListener(activity, task -> {
if (task.isSuccessful()) {
// Set the map's camera position to the current location of the device.
mLastKnownLocation = (Location) task.getResult();
if (mLastKnownLocation == null) {
updateStartedInternally = true;
mFusedLocationProviderClient.requestLocationUpdates(mLocationRequest, mLocationCallback, Looper.myLooper());
} else {
onLocationUpdateListener.onLocationChange(mLastKnownLocation);
}
} else {
onLocationUpdateListener.onError("Can't get Location");
}
});
} catch (SecurityException e) {
Log.e("Exception: %s", e.getMessage());
onLocationUpdateListener.onError(e.getMessage());
}
}
public void startLocationUpdates() {
if (ActivityCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
updateStartedInternally = false;
mFusedLocationProviderClient.requestLocationUpdates(mLocationRequest, mLocationCallback, Looper.myLooper());
}
private void stopLocationUpdate() {
mFusedLocationProviderClient.removeLocationUpdates(mLocationCallback);
}
//other new Methods but not using right now..
protected void createLocationRequest() {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(10000);//set the interval in which you want to get locations
mLocationRequest.setFastestInterval(5000);//if a location is available sooner you can get it (i.e. another app is using the location services)
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
}
}
where OnLocationUpdateListener is
public interface OnLocationUpdateListener {
void onLocationChange(Location location);
void onError(String error);
}