How to wait for a OnOcation Result before continuing when getting the device location in android

Question

I have an application in which I need to get the device location , in my code after getting the device's location i store them in shared preferences and then after clicking on a button I retrieve the latitude and longitude and use them in other method calls , but sometimes after activating the GPS and calling the "getCurrentLocation" method (Listed below) , I got error saying that the latitude and longitude values stored in shared prefs are null even if I made a loading screen that lasts 8 seconds after calling the getCurrentLocation method in order to wait for to return value , how to make my app wait for the getCurrent Location methid untill it returnsa value ??

Lets say that I am calling it on the OnCreate lifecycle method or onButton click , how to wait for it to return a value ??

public void getCurrentLocation(Activity currentActivity) {

        LocationRequest request = new LocationRequest();
        request.setInterval(10000);
        request.setFastestInterval(5000);
        request.setPriority(request.PRIORITY_HIGH_ACCURACY);
        FusedLocationProviderClient client =
                LocationServices.getFusedLocationProviderClient(currentActivity);
        int permission = ContextCompat.checkSelfPermission(currentActivity,
                Manifest.permission.ACCESS_FINE_LOCATION);
        if (permission == PackageManager.PERMISSION_GRANTED) {
            // Request location updates and when an update is
            // received, update text view
            client.requestLocationUpdates(request, new LocationCallback() {
                @Override
                public void onLocationResult(LocationResult locationResult) {
                    Location location = locationResult.getLastLocation();
                    if (location != null) {

                        // Use the location object to get Latitute and Longitude and then update your text view.
                        currentLocation = location;
                        sharedPreferences = getSharedPreferences(getPackageName() + ".prefs", Context.MODE_PRIVATE);
                        editor = sharedPreferences.edit();

                        editor.putString("lat", String.valueOf(location.getLatitude()));
                        editor.putString("lng", String.valueOf(location.getLongitude()));
                        editor.apply();

//                        Intent i = new Intent(currentActivity,Loading.class);
//                        startActivity(i);


                    }
                }

            }, null);

        }
    }

Answer 1

Location Data on Maps SDK for Android has the ActivityCompat.OnRequestPermissionsResultCallback callback function which you can utilize to check if you have accessed the device location or not.

For example:

public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    if (requestCode != LOCATION_PERMISSION_REQUEST_CODE) {
        return;
    }

    if (PermissionUtils.isPermissionGranted(permissions, grantResults, Manifest.permission.ACCESS_FINE_LOCATION)) {
        // Permission to access device location has been granted
        // Do next task here
        enableMyLocation();
    } else {
        // Permission was denied. Display an error message
        // Display the missing permission error dialog when the fragments resume.
        permissionDenied = true;
    }
}