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How to use getCurrentLocation of fused location provider client?

I am new for Android coding, and have writen a code to get location of Android Device but failed. Nothing changed (e.g. mLastKnownLocation or cityName) after runing, and no expception. I have already checked permission and build.gradle. Could you give me advices to implement it?
private void getDeviceLocation() {
try {
if (mLocationPermissionGranted) {
Task<Location> locationResult = mFusedLocationProviderClient.getCurrentLocation(Priority.PRIORITY_HIGH_ACCURACY,cancellationToken);
//Task<Location> locationResult = mFusedLocationProviderClient.getLastLocation();
locationResult.addOnCompleteListener(this, new OnCompleteListener<Location>(){
#Override
public void onComplete(#NonNull Task<Location> task) {
if (task.isSuccessful()) {
// Obtain the current location of the device
mLastKnownLocation = task.getResult();
String currentOrDefault = "Current";
if (mLastKnownLocation != null) {
Log.d(TAG, "Get current location");
} else {
Log.d(TAG, "Current location is null. Using defaults.");
currentOrDefault = "Default";
// Set current location to the default location
mLastKnownLocation = new Location("");
mLastKnownLocation.setLatitude(mDefaultLocation.latitude);
mLastKnownLocation.setLongitude(mDefaultLocation.longitude);
}
String city = "CorrectCity";
try {
List<Address> address =
geocoder.getFromLocation(mLastKnownLocation.getLatitude(),
mLastKnownLocation.getLongitude(), 1);
if(address.isEmpty())
city = "No_city";
else{
Address target = address.get(0);
if(target.getLocality()!=null)
city = target.getLocality();
else
city = target.getAdminArea();}
} catch (IOException e) {
Log.e("Exception: %s", e.getMessage());
}
cityName = city;
// Show location details on the location TextView
String msg = currentOrDefault + " Location: " +
Double.toString(mLastKnownLocation.getLatitude()) + ", " +
Double.toString(mLastKnownLocation.getLongitude())+ " " +
cityName;
locationTextView.setText(msg);
} else {
Log.d(TAG, "Current location is null. Using defaults.");
Log.e(TAG, "Exception: %s", task.getException());
/*mMap.moveCamera(CameraUpdateFactory
.newLatLngZoom(mDefaultLocation, DEFAULT_ZOOM));
mMap.getUiSettings().setMyLocationButtonEnabled(false);*/
}
}
});
}
} catch (SecurityException e) {
Log.e("Exception: %s", e.getMessage());
cityName = "ErrorCity";
}
}
}

You can get your last known location using the code below
FusedLocationProviderClient fusedLocationClient = LocationServices.getFusedLocationProviderClient(getContext());
fusedLocationClient.getLastLocation().addOnSuccessListener(location -> {
if (location != null) {
// your last known location is stored in `location`
}
});
refer: https://developer.android.com/training/location/retrieve-current
Using Location Manager
LocationManager manager = (LocationManager) this.getSystemService(LOCATION_SERVICE);
LocationListener listener = new LocationListener() {
#Override
public void onLocationChanged(#NonNull Location location) {
mMap.clear();
LatLng userLocation = new LatLng(location.getLatitude(), location.getLongitude());
mMap.addMarker(new MarkerOptions().position(userLocation).title("Me"));
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(userLocation, 15));
}
#Override
public void onProviderEnabled(#NonNull String provider) {
}
#Override
public void onProviderDisabled(#NonNull String provider) {
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
};
manager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, listener);

How to return current location on flutter using native android code in java

I am trying to get current location using native code for my flutter app.
It seemed more doable to implement something similar to Google Maps where the app asks the user whether they would like location turned on or not and if they say ok, then location is turned on automatically. I have been able to do this successfully but I also want to return the current location back to the flutter end. Now, I am obtaining the user action from onActivityResult() and then running the getLastLocation() method if resultCode == RESULT_OK. However, I want the flutter end to wait until the current location is obtained. I have tried using a lock mechanism but this causes the app to freeze. Currently, I have the naive implementation of just using Thread.sleep(long millis) until an affirmative result has been obtained at which point the result would be returned back to flutter.
This is the code to turn location on:
private void turnLocationOn(Context context) {
GoogleApiClient googleApiClient = new GoogleApiClient.Builder(context)
.addApi(LocationServices.API).build();
googleApiClient.connect();
LocationRequest locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(10000);
locationRequest.setFastestInterval(10000 / 2);
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder()
.addLocationRequest(locationRequest);
builder.setAlwaysShow(true);
Task<LocationSettingsResponse> result = LocationServices.getSettingsClient(this)
.checkLocationSettings(builder.build());
result.addOnCompleteListener(new OnCompleteListener<LocationSettingsResponse>() {
#Override
public void onComplete(#NonNull Task<LocationSettingsResponse> task) {
try {
LocationSettingsResponse response =
task.getResult(ApiException.class);
} catch (ApiException ex) {
switch (ex.getStatusCode()) {
case LocationSettingsStatusCodes
.RESOLUTION_REQUIRED:
try {
ResolvableApiException resolvableApiException =
(ResolvableApiException) ex;
resolvableApiException
.startResolutionForResult(MainActivity.this,
LOCATION_SETTINGS_REQUEST);
} catch (IntentSender.SendIntentException e) {
e.printStackTrace();
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
break;
}
}
}
});
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == LOCATION_SETTINGS_REQUEST) {
if (resultCode == RESULT_OK)
{
Log.i(TAG, "User turned on location");
callResult = true;
} else if (resultCode == RESULT_CANCELED) {
Log.i(TAG, "User declined location setting request");
callResult = false;
// setCallResult(false);
}
}
}
This is the method that sets the current location. It is an implementation of LocationListener:
#Override
public void onLocationChanged(Location location) {
callResult = true;
currLocation = location.getLatitude() + ", " + location.getLongitude();
}
This is the Method channel that returns a result back to flutter
new MethodChannel(getFlutterView(), CHANNEL).setMethodCallHandler(
new MethodChannel.MethodCallHandler() {
#Override
public void onMethodCall(MethodCall methodCall, MethodChannel.Result result) {
if (methodCall.method.equals("getCurrentLocation")) {
turnLocationOn(MainActivity.this);
while (!callResult) {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
result.success(currLocation);
} else {
result.notImplemented();
}
}
});
...and this is from the flutter end
final String result = await platform.invokeMethod('getCurrentLocation');
resultFromCall = "SUCCESS: $result";
debugPrint(resultFromCall);

Android - How to request location update in the new API?

I was playing a bit around the new location API from google (to get latitude and longitude values):
private void getLastLocation(){
FusedLocationProviderClient mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
try {
mFusedLocationClient.getLastLocation().addOnSuccessListener(new OnSuccessListener<Location>() {
#Override
public void onSuccess(Location location) {
if (location != null) {
double latitude = location.getLatitude();
double longitude = location.getLongitude();
Toast.makeText(getApplicationContext(), String.valueOf(latitude) + "/" + String.valueOf(longitude), Toast.LENGTH_LONG).show();
} else {
Toast.makeText(getApplicationContext(), "Cannot get location", Toast.LENGTH_LONG).show();
}
}
})
.addOnFailureListener(new OnFailureListener() {
#Override
public void onFailure(#NonNull Exception e) {
Log.d("LocationFetch", "Error trying to get last GPS location");
e.printStackTrace();
}
});
} catch (SecurityException e){
Log.d("LocationFetch", "Permission missing");
}
}
When I first tested this code, the location was always returning null. However, after opening Instagram (which did a location update on my phone - the geo icon appeared briefly), the location was returning my relevant longitude and latitude values.
How do I request a location update on my app using the new API to prevent location from being null or retrieve very old locations? (getLastLocation() is not enough, possibly LocationRequest?)
It is worth noting that I do not want interval updates, I want for it to happen within an Android Service when invoked once.

Firstly add this implementation in your build.gradle file
implementation 'com.google.android.gms:play-services-location:11.2.0'//include the latest version of play services
After that implement, (implements LocationListener) in your activity or fragment and after that implement its function and then
call this method in your onCreate() getLocation();
and then in this function add these lines
protected void getLocation() {
if (isLocationEnabled(MainActivity.this)) {
locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
criteria = new Criteria();
bestProvider = String.valueOf(locationManager.getBestProvider(criteria, true)).toString();
//You can still do this if you like, you might get lucky:
Location location = locationManager.getLastKnownLocation(bestProvider);
if (location != null) {
Log.e("TAG", "GPS is on");
latitude = location.getLatitude();
longitude = location.getLongitude();
Toast.makeText(MainActivity.this, "latitude:" + latitude + " longitude:" + longitude, Toast.LENGTH_SHORT).show();
searchNearestPlace(voice2text);
}
else{
//This is what you need:
locationManager.requestLocationUpdates(bestProvider, 1000, 0, this);
}
}
else
{
//prompt user to enable location....
//.................
}
}
After that in your onLocationChanged(Location location)
add these lines of code
#Override
public void onLocationChanged(Location location) {
//Hey, a non null location! Sweet!
//remove location callback:
locationManager.removeUpdates(this);
//open the map:
latitude = location.getLatitude();
longitude = location.getLongitude();
Toast.makeText(MainActivity.this, "latitude:" + latitude + " longitude:" + longitude, Toast.LENGTH_SHORT).show();
searchNearestPlace(voice2text);
}
and you are set to go!!!!
Cheers Happy Coding

It's work for me. Based on Official docs, every 10 seconds updates the Toast and shows your location:
private FusedLocationProviderClient fusedLocationClient;
private LocationRequest locationRequest;
private LocationCallback locationCallback;
#Override
protected void onResume() {
super.onResume();
startLocationUpdates();
}
private void startLocationUpdates() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// Activity#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 Activity#requestPermissions for more details.
return;
}
}
fusedLocationClient.requestLocationUpdates(locationRequest,
locationCallback,
Looper.getMainLooper());
}
#Override
protected void onPause() {
super.onPause();
stopLocationUpdates();
}
private void stopLocationUpdates() {
fusedLocationClient.removeLocationUpdates(locationCallback);
}
add bellow codes to onCreate method:
fusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(2*5000);
locationCallback=new LocationCallback(){
#Override
public void onLocationResult(LocationResult locationResult) {
if (locationResult == null) {
return;
}
for (Location location : locationResult.getLocations()) {
// if (location != null) {
String Lat = String.valueOf(location.getLatitude());
String Lon = String.valueOf(location.getLongitude());
Toast.makeText(getApplicationContext(), Lat + " - " + Lon, Toast.LENGTH_SHORT).show();
// }
}
}
};

Try this code.
In gradle
implementation 'com.google.android.gms:play-services-location:16.0.0'
In code
private void turnGPSOn() {
LocationRequest mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(10 * 1000)
.setFastestInterval(1 * 1000);
LocationSettingsRequest.Builder settingsBuilder = new LocationSettingsRequest.Builder()
.addLocationRequest(mLocationRequest);
settingsBuilder.setAlwaysShow(true);
Task<LocationSettingsResponse> result = LocationServices.getSettingsClient(this)
.checkLocationSettings(settingsBuilder.build());
result.addOnCompleteListener(new OnCompleteListener<LocationSettingsResponse>() {
#Override
public void onComplete(#NonNull Task<LocationSettingsResponse> task) {
try {
LocationSettingsResponse response =
task.getResult(ApiException.class);
if (gps.canGetLocation()) {
lat = String.valueOf(gps.getLatitude());
lon = String.valueOf(gps.getLongitude());
}
} catch (ApiException ex) {
switch (ex.getStatusCode()) {
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
try {
ResolvableApiException resolvableApiException =
(ResolvableApiException) ex;
resolvableApiException
.startResolutionForResult(SignupActivity.this,
REQUEST_CHECK_SETTINGS);
} catch (IntentSender.SendIntentException e) {
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
break;
}
}
}
});
}

Wait for device to fetch location data

In my app I fetch GPS coordinates from the user. When the GPS was just activated my app continues even before the coordinates were fetched, so the location is null.
I noticed that the onLocationChanged method does as it should and might somehow be a key to it, but how do I make sure that the code in the main class doesn’t fetch empty values and waits until the location is not null?
The main code:
if (ContextCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
requestPermissions(new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 1);
} else {
progressBar.setVisibility(View.VISIBLE);
GPSFetch t = new GPSFetch(getActivity().getApplicationContext());
Location location = t.getLocation();
if (location == null) {
//Toast
} else {
lat = location.getLatitude();
lon = location.getLongitude();
}
new GetContacts().execute();
}
The GPSFetch:
public Location getLocation(){
if (ContextCompat.checkSelfPermission( context, android.Manifest.permission.ACCESS_FINE_LOCATION ) != PackageManager.PERMISSION_GRANTED)
{
return null;
}
try {
LocationManager lm = (LocationManager) context.getSystemService(LOCATION_SERVICE);
boolean isGPSEnabled = lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
if (isGPSEnabled){
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 5000,10,this);
Location loc = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
return loc;
}else{
}
}catch (Exception e){
e.printStackTrace();
}
return null;
}
#Override
public void onLocationChanged(Location location) {
Log.d("4", "changed");
}

The method is called onLocationChanged. Which means that there IS a value.
Note: You are actually fetching a GPS coordinate from the local play services api of the android device. Read more about location services here

First you check your gps is on or not, if gps is on then onlocation changed method give lat and lon.
you can check using following code
public static boolean checkGps(Activity mContext) {
LocationManager service = (LocationManager) mContext.getSystemService(LOCATION_SERVICE);
boolean enabled = service.isProviderEnabled(LocationManager.GPS_PROVIDER);
return enabled;
}
its return true then gps on otherwise not
if gps not on then on gps programatically using this code
public void displayLocationSettingsRequest() {
GoogleApiClient googleApiClient = new GoogleApiClient.Builder(this)
.addApi(LocationServices.API).build();
googleApiClient.connect();
LocationRequest locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(10000);
locationRequest.setFastestInterval(10000 / 2);
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder().addLocationRequest(locationRequest);
builder.setAlwaysShow(true);
PendingResult<LocationSettingsResult> result = LocationServices.SettingsApi.checkLocationSettings(googleApiClient, builder.build());
result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
#Override
public void onResult(LocationSettingsResult result) {
final Status status = result.getStatus();
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
Log.e("LocationSetting.SUCCESS", "All location settings are satisfied.");
// openMap();
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
Log.e("LocationSetting.SUCCESS", "Location settings are not satisfied. Show the user a dialog to upgrade location settings ");
try {
// Show the dialog by calling startResolutionForResult(), and check the result
// in onActivityResult().
status.startResolutionForResult(HomeActivity.this, REQUEST_CHECK_SETTINGS);
} catch (IntentSender.SendIntentException e) {
Log.e("LocationSetting.SUCCESS", "PendingIntent unable to execute request.");
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
Log.e("LocationSetting.SUCCESS", "Location settings are inadequate, and cannot be fixed here. Dialog not created.");
break;
}
}
});
}
this ask you about gps on or cancel if you press ok then you can fetch result of its in onactivityresult method
like this
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 100) {
if (resultCode == Activity.RESULT_OK) {
String result = data.getStringExtra("result");
Log.e("RESULT_OK", result + "");
// now your gps is on you can handle your location code here
}
if (resultCode == Activity.RESULT_CANCELED) {
Utils.showToastPopup(this, "Please Turn On Gps");
// show custom popup when user denied this gps permission and check again
when click button or on resume
}
}
}
and then fetch your lat lon inside onlocationchanged
#Override
public void onLocationChanged(Location location) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}

Google Maps API shows location, but doesn't center

I'm working with the Google Maps API in Android Studio 2.2.3 and for some reason the location button works, but it doesn't center. Furthermore, I get a toast with the message that there no location was found.
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_map);
getLocationPermission();
}
private void getDeviceLocation() {
Log.d(TAG, "getDeviceLocation: getting the devices current location");
mFusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this);
try {
if (mLocationPermissionsGranted) {
Task location = mFusedLocationProviderClient.getLastLocation();
location.addOnCompleteListener(new OnCompleteListener() {
#Override
public void onComplete(#NonNull Task task) {
if (task.isSuccessful() && task.getResult() != null) {
Log.d(TAG, "onComplete: found location");
Location currentLocation = (Location) task.getResult();
moveCamera(new LatLng(currentLocation.getLatitude(), currentLocation.getLongitude()),
DEFAULT_ZOOM);
} else {
Log.d(TAG, "onComplete: current location is null");
Toast.makeText(MapActivity.this, "unable to get current location", Toast.LENGTH_SHORT).show();
Location currentLocation = (Location) task.getResult();
}
}
});
}
} catch (SecurityException e) {
}
}
The above code is what I to believe the code for finding the location, and then positioning the camera to that given location. I do not get any errors and when I set the LocationButton to true, and then click on it, it does center to my location.

By changing that code to
private void getDeviceLocation(){
try{
if(mLocationPermissionGranted){
Task locationResult = mFusedLocationProviderClient.getLastLocation();
locationResult.addOnCompleteListener(this, new OnCompleteListener() {
#Override
public void onComplete(#NonNull Task task) {
if(task.isSuccessful() && task.getResult() != null){
Log.d(TAG, "onComplete: location found!");
Location currentLocation = (Location) task.getResult();
float currentZoom = mMap.getCameraPosition().zoom;//edit (added line)
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(currentLocation.getLatitude(),
currentLocation.getLongitude()), DEFAULT_ZOOM));//edit (changed line)
}else{
Log.d(TAG, "onComplete: current location is null");
Toast.makeText(MapActivity.this, "unable to get current location", Toast.LENGTH_SHORT).show();
}
}
});
}
}catch (SecurityException e){
}
}
I managed so get a return with a location, after I manually set the location for the device because for some reason the location doesn't get determined rightaway.
For now the problem is solved!

Tried your code.
It didn't work for me but I solved the problem.
Here is the correct code.
private void getDeviceLocation(){
mFusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this);
try{
if(mLocationPermissionGranted){
Task location = mFusedLocationProviderClient.getLastLocation();
location.addOnCompleteListener(new OnCompleteListener() {
#Override
public void onComplete(#NonNull Task task) {
if(task.isSuccessful() && task.getResult() != null){
Toast.makeText(DriverMapActivity.this, "Task is successful", Toast.LENGTH_SHORT).show();
Location currentLocation = (Location) task.getResult();
mLatLng = new LatLng(currentLocation.getLatitude(), currentLocation.getLongitude());
moveCamera(mLatLng, DEFAULT_ZOOM);
}else{
Toast.makeText(DriverMapActivity.this, "Task is unsuccessful", Toast.LENGTH_SHORT).show();
}
}
});
}
}catch (SecurityException e){
Toast.makeText(this, "SecurityException Found", Toast.LENGTH_SHORT).show();
}
}
So, if your app is crashing, you might wanna try this instead.