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Start Gps Tracking again when the android application On-Resumes()

I have build a system which is based upon tracking users current location dynamically as they move around places. The system works perfectly and updates current location of the users time after time into the firebase database. however when the application is minimized and resumed again to the same activity which is a map of course, it only shows the location of the user but does not update it in the fire-base database. now i know that the activity starts again from the OnResume() method, i have tried several things but every time i try to do something, it most of the time says that googleapiClient is not connected and then crashes right away. without manipulating the onResume, the app works perfectly but that does not update user position into the fire-base when the app is minimized and reopened from the onResume method. What should i do to the onResume() method that it starts sending user dynamic location into the firebase???
Below i have posted my code. Any help would be appreciated Thank You.
public class RequestLocationMap extends FragmentActivity implements OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks
, GoogleApiClient.OnConnectionFailedListener
, LocationListener {
private static final String TAG = "RequestLocationMap";
private GoogleMap mMap;
private GoogleApiClient googleApiClient;
private LocationRequest locationRequest;
private Location lastLocation;
private Marker currentUserLocationMarker;
public static final int Request_User_Location_Code = 99;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_request_location_map);
Log.d(TAG, "onCreate: called");
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
checkUserLocationPermission();
}
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
}
#Override
public void onMapReady(GoogleMap googleMap) {
Log.d(TAG, "onMapReady: called");
mMap = googleMap;
if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
buildGoogleApiClient();
mMap.setMyLocationEnabled(true);
}
}
public boolean checkUserLocationPermission() {
Log.d(TAG, "checkUserLocationPermission: called");
if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.ACCESS_FINE_LOCATION)) {
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, Request_User_Location_Code);
} else {
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, Request_User_Location_Code);
}
return false;
} else {
return true;
}
}
#Override
public void onRequestPermissionsResult(int requestCode, #NonNull String[] permissions, #NonNull int[] grantResults) {
Log.d(TAG, "onRequestPermissionsResult: here");
switch (requestCode) {
case Request_User_Location_Code:
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
if (googleApiClient == null) {
buildGoogleApiClient();
}
mMap.setMyLocationEnabled(true);
}
} else {
Toast.makeText(this, "Application requires location permission", Toast.LENGTH_SHORT).show();
}
}
}
protected synchronized void buildGoogleApiClient() {
Log.d(TAG, "buildGoogleApiClient: called");
googleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
googleApiClient.connect();
}
#Override
public void onConnected(#Nullable Bundle bundle) {
Log.d(TAG, "onConnected: called");
locationRequest = new LocationRequest();
locationRequest.setInterval(1000);
locationRequest.setFastestInterval(1000);
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
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();
final LocationSettingsStates state = result.getLocationSettingsStates();
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
try {
status.startResolutionForResult(
RequestLocationMap.this, 1000);
} catch (IntentSender.SendIntentException e) {
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
break;
}
}
});
if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
LocationServices.FusedLocationApi.requestLocationUpdates(googleApiClient, locationRequest, this);
}
}
#Override
public void onConnectionSuspended(int i) {
}
#Override
public void onConnectionFailed(#NonNull ConnectionResult connectionResult) {
}
#Override
public void onLocationChanged(Location location) {
Log.d(TAG, "onLocationChanged: called");
lastLocation = location;
if (currentUserLocationMarker != null) {
currentUserLocationMarker.remove();
}
LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title("Current Location");
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED));
currentUserLocationMarker = mMap.addMarker(markerOptions);
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
mMap.animateCamera(CameraUpdateFactory.zoomTo(14f));
DatabaseReference myTracking = FirebaseDatabase.getInstance().getReference().child("MyTracking");
GeoFire geoFire = new GeoFire(myTracking);
geoFire.setLocation(FirebaseAuth.getInstance().getCurrentUser().getUid(), new GeoLocation(location
.getLatitude(), location.getLongitude()));
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
Log.d(TAG, "onActivityResult: called");
switch (requestCode) {
case 1000:
switch (resultCode) {
case Activity.RESULT_OK: {
break;
}
case Activity.RESULT_CANCELED: {
// The user was asked to change settings, but chose not to
Toast.makeText(RequestLocationMap.this, "App required location permission", Toast.LENGTH_LONG).show();
finish();
break;
}
default: {
break;
}
}
break;
}
}
#Override
protected void onStop() {
Log.d(TAG, "onStop: called");
super.onStop();
LocationServices.FusedLocationApi.removeLocationUpdates(googleApiClient, this);
DatabaseReference myTracking = FirebaseDatabase.getInstance().getReference().child("MyTracking");
GeoFire geoFire = new GeoFire(myTracking);
geoFire.removeLocation(FirebaseAuth.getInstance().getCurrentUser().getUid());
}
#Override
protected void onResume() {
Log.d(TAG, "onResume: called");
super.onResume();
}
}

The problem with your app is that in the lifecycle method onStop() you request to stop receiving location updates from the FusedLocation API, but in the reciprocal method of onResume(). you never request for location updates. Furthermore, with the way your code is structured even if you did register for location updates inside of onResume(), you'd run into a problem with the GoogleClient API because it may not (more than likely, isn't) connected by the time onResume() gets executed.
I recommend that you call the method buildGoogleApiClient() from onResume instead of onCreate() (still perform the permissions check). This way the GoogleClient API is always connected while the activity is resumed. Remember to call "disconnect" on the GoogleClient API inside of onPause(). Inside of the location listener callback method you should perform a null check on the GoogleMap reference to prevent any NP-exceptions. GoogleMaps may be null during the first few executions of onLocationChanged(Location) because it may take more time to initialize the MapFragment than it does to receive the first location update from the FusedLocation API. I've seen the location API deliver a location update milliseconds after I requested updates.
Also, just good practice you should pair lifecycle methods with their reciprocals:
onCreate() -> onDestroy()
onStart() -> onStop()
onResume -> onPause()
Mixing and matching lifecycle callbacks can bite you down the line when you expecting a happens-before relationship, such as registering and deregistering for location updates when the app is paused and resumed.

display current location in MapFragment

I have a location class which creates an instance on MapFragment, and dependant on which activity the map is created from, will drop a different marker. I would also like the map to display a marker for the phones current location.
I'm assuming I can do something like this, but I cant work out how to get and update the phones current coordinates and assign that to myLocation.
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_location);
MapFragment googleMap = (MapFragment) getFragmentManager().findFragmentById(R.id.map);
googleMap.getMapAsync(this);
}
#Override
public void onMapReady(GoogleMap nMap){
if(MainMenu.bkSource == true) {
LatLng bkLatLng = new LatLng(54.5816008, -5.9651271);
LatLng myLocation = new LatLng(???);
nMap.addMarker(new MarkerOptions().position(bkLatLng).title("Burger King, Boucher Road"));
nMap.addMarker(new MarkerOptions().position(myLocation).title("You Are Here");
nMap.moveCamera(CameraUpdateFactory.newLatLngZoom(bkLatLng, 15));
nMap.animateCamera(CameraUpdateFactory.zoomTo(18.0f));
}
if(MainMenu.kfcSource == true){
LatLng bkLatLng = new LatLng(54.5771914, -5.9620562);
nMap.addMarker(new MarkerOptions().position(bkLatLng).title("KFC, Boucher Road"));
nMap.moveCamera(CameraUpdateFactory.newLatLngZoom(bkLatLng, 15));
nMap.animateCamera(CameraUpdateFactory.zoomTo(18.0f));
}
if(MainMenu.mcdSource == true){
LatLng bkLatLng = new LatLng(54.5879486, -5.9580009);
nMap.addMarker(new MarkerOptions().position(bkLatLng).title("McDonald's, Boucher Road"));
nMap.moveCamera(CameraUpdateFactory.newLatLngZoom(bkLatLng, 15));
nMap.animateCamera(CameraUpdateFactory.zoomTo(18.0f));
}
}

Here is an example Fragment that extends SupportMapFragment, on launch it will get the user's current location, place a Marker, and zoom in:
public class MapFragment extends SupportMapFragment
implements OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
GoogleMap mGoogleMap;
SupportMapFragment mapFrag;
LocationRequest mLocationRequest;
GoogleApiClient mGoogleApiClient;
Location mLastLocation;
Marker mCurrLocationMarker;
#Override
public void onResume() {
super.onResume();
setUpMapIfNeeded();
}
private void setUpMapIfNeeded() {
if (mGoogleMap == null) {
getMapAsync(this);
}
}
#Override
public void onPause() {
super.onPause();
//stop location updates when Activity is no longer active
if (mGoogleApiClient != null) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
}
}
#Override
public void onMapReady(GoogleMap googleMap)
{
mGoogleMap=googleMap;
mGoogleMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
//Initialize Google Play Services
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (ContextCompat.checkSelfPermission(getActivity(),
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
//Location Permission already granted
buildGoogleApiClient();
mGoogleMap.setMyLocationEnabled(true);
} else {
//Request Location Permission
checkLocationPermission();
}
}
else {
buildGoogleApiClient();
mGoogleMap.setMyLocationEnabled(true);
}
}
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(getActivity())
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mGoogleApiClient.connect();
}
#Override
public void onConnected(Bundle bundle) {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(1000);
mLocationRequest.setFastestInterval(1000);
mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
if (ContextCompat.checkSelfPermission(getActivity(),
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
}
#Override
public void onConnectionSuspended(int i) {}
#Override
public void onConnectionFailed(ConnectionResult connectionResult) {}
#Override
public void onLocationChanged(Location location)
{
mLastLocation = location;
if (mCurrLocationMarker != null) {
mCurrLocationMarker.remove();
}
//Place current location marker
LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title("Current Position");
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
mCurrLocationMarker = mGoogleMap.addMarker(markerOptions);
//move map camera
mGoogleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng,11));
}
public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
private void checkLocationPermission() {
if (ContextCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
// Should we show an explanation?
if (ActivityCompat.shouldShowRequestPermissionRationale(getActivity(),
Manifest.permission.ACCESS_FINE_LOCATION)) {
// Show an explanation to the user *asynchronously* -- don't block
// this thread waiting for the user's response! After the user
// sees the explanation, try again to request the permission.
new AlertDialog.Builder(getActivity())
.setTitle("Location Permission Needed")
.setMessage("This app needs the Location permission, please accept to use location functionality")
.setPositiveButton("OK", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
//Prompt the user once explanation has been shown
ActivityCompat.requestPermissions(getActivity(),
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION );
}
})
.create()
.show();
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(getActivity(),
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION );
}
}
}
#Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_LOCATION: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// permission was granted, yay! Do the
// location-related task you need to do.
if (ContextCompat.checkSelfPermission(getActivity(),
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
if (mGoogleApiClient == null) {
buildGoogleApiClient();
}
mGoogleMap.setMyLocationEnabled(true);
}
} else {
// permission denied, boo! Disable the
// functionality that depends on this permission.
Toast.makeText(getActivity(), "permission denied", Toast.LENGTH_LONG).show();
}
return;
}
// other 'case' lines to check for other
// permissions this app might request
}
}
}
Since the Location permission request needs to go through the Activity, you will need to route the result from the Activity to the Fragment's onRequestPermissionsResult() method:
public class MainActivity extends AppCompatActivity {
MapFragment mapFragment;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
mapFragment = new MapFragment();
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.add(R.id.mapframe, mapFragment);
transaction.commit();
}
#Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
if (requestCode == MapFragment.MY_PERMISSIONS_REQUEST_LOCATION){
mapFragment.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
else {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
}
}
The layout just contains a FrameLayout where the MapFragment goes.
activity_main.xml:

Use the following code for get current location:
#Override
public void onMapReady(GoogleMap googleMap) {
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) {
// 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;
}
mMap.setMyLocationEnabled(true);
}
If you want to add marker in current Location try this:
1.Implement LocationListener In your Activity.
2.Update LocationRequest:
LocationRequest mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(5000); //5 seconds
mLocationRequest.setFastestInterval(3000); //3 seconds
mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
3.create your marker on onLocationChanged(Location location)
Geocoder geocoder;
List<Address> addresses;
geocoder = new Geocoder(this, Locale.getDefault());
//place marker at current position
//mGoogleMap.clear();
Marker currLocationMarker;
if (currLocationMarker != null) {
currLocationMarker.remove();
}
latLng = new LatLng(location.getLatitude(), location.getLongitude());
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title("Current Position.......");
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
currLocationMarker = mMap.addMarker(markerOptions);
}
}

Map marker doesn't track me

I have an app: Map&Location. When I move the blue point indicator moves along with me but the marker doesn't. It stays fixed in one place, does anybody know what the problem is?
public class MapsActivity extends AppCompatActivity implements OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
GoogleMap mGoogleMap;
SupportMapFragment mapFrag;
LocationRequest mLocationRequest;
GoogleApiClient mGoogleApiClient;
Location mLastLocation;
Marker mCurrLocationMarker;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
checkLocationPermission();
}
mapFrag = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
mapFrag.getMapAsync(this);
}
#Override
public void onPause() {
super.onPause();
//stop location updates when Activity is no longer active
if (mGoogleApiClient != null) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
}
}
#Override
public void onMapReady(GoogleMap googleMap) {
mGoogleMap=googleMap;
mGoogleMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
//Initialize Google Play Services
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (ContextCompat.checkSelfPermission(this,
android.Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
buildGoogleApiClient();
mGoogleMap.setMyLocationEnabled(true);
}
}
else {
buildGoogleApiClient();
mGoogleMap.setMyLocationEnabled(true);
}
}
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mGoogleApiClient.connect();
}
#Override
public void onConnected(#Nullable Bundle bundle) {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(1000);
mLocationRequest.setFastestInterval(1000);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
}
#Override
public void onConnectionSuspended(int i) {
}
#Override
public void onConnectionFailed(#NonNull ConnectionResult connectionResult) {
}
#Override
public void onLocationChanged(Location location) {
mLastLocation = location;
if (mCurrLocationMarker != null) {
mCurrLocationMarker.remove();
}
//Place current location marker
LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title("Current Position");
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
mCurrLocationMarker = mGoogleMap.addMarker(markerOptions);
//move map camera
mGoogleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
mGoogleMap.animateCamera(CameraUpdateFactory.zoomTo(11));
//stop location updates
if (mGoogleApiClient != null) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
}
Geocoder geocoder = new Geocoder(getApplicationContext(), Locale.getDefault());
try {
List<Address> listAddress = geocoder.getFromLocation(location.getLatitude(),location.getLongitude(),1);
if(listAddress!=null&&listAddress.size()>0){
Log.i("Place info",listAddress.get(0).toString());
}
} catch (IOException e) {
e.printStackTrace();
}
}
public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
public boolean checkLocationPermission(){
if (ContextCompat.checkSelfPermission(this,
android.Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
// Should we show an explanation?
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
android.Manifest.permission.ACCESS_FINE_LOCATION)) {
//TODO:
// Show an expanation to the user *asynchronously* -- don't block
// this thread waiting for the user's response! After the user
// sees the explanation, try again to request the permission.
//Prompt the user once explanation has been shown
//(just doing it here for now, note that with this code, no explanation is shown)
ActivityCompat.requestPermissions(this,
new String[]{android.Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION);
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(this,
new String[]{android.Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION);
}
return false;
} else {
return true;
}
}
#Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_LOCATION: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// permission was granted, yay! Do the
// location-related task you need to do.
if (ContextCompat.checkSelfPermission(this,
android.Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
if (mGoogleApiClient == null) {
buildGoogleApiClient();
}
mGoogleMap.setMyLocationEnabled(true);
}
} else {
// permission denied, boo! Disable the
// functionality that depends on this permission.
Toast.makeText(this, "permission denied", Toast.LENGTH_LONG).show();
}
return;
}
// other 'case' lines to check for other
// permissions this app might request
}
}
}

You are removing location update when the first onLocationChange triggers.
Remove these lines:
//stop location updates
if (mGoogleApiClient != null) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
}

Android : Display Markers in MapActivity

This code below currently shows location of device. I am getting JSON from URL, and parsing it below. I want to display this as Markers in my MapActivity. I am getting java.lang.NullPointerException on mMap.addMarket(_markeroptions).
I am getting JSON data, that part is working, just not able to display it on Map. Your guidance will be helpful.
public class MapActivity extends FragmentActivity implements OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
// Add stDisplayListView code here
JSONArray jsonArray;
String json_string;
// End stDisplayListView
public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
LocationRequest mLocationRequest;
GoogleApiClient mGoogleApiClient;
private GoogleMap mMap;
Location mLastLocation;
Marker mCurrLocationMarker;
Marker doctorLocationMarker;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_map);
// int x =_st.jsonArray.length();
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
checkLocationPermission();
}
// Obtain the SupportMapFragment and get notified when the map is ready to be used.
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
}
/**
* Manipulates the map once available.
* This callback is triggered when the map is ready to be used.
* This is where we can add markers or lines, add listeners or move the camera. In this case,
* we just add a marker near Sydney, Australia.
* If Google Play services is not installed on the device, the user will be prompted to install
* it inside the SupportMapFragment. This method will only be triggered once the user has
* installed Google Play services and returned to the app.
*/
#Override
public void onMapReady(GoogleMap googleMap) {
// int count = _st.doctorAdapter.getCount();
// int i =1;
json_string = getIntent().getExtras().getString("JSON_DTA");
try {
int count =0 ;
//jsonObject = new JSONObject(json_string);
jsonArray = new JSONArray(json_string);
int _id;
String _doctorname;
String _doclat;
String _doclong;
//List<Marker> markers = new ArrayList<Marker>();
while(count < jsonArray.length())
{
JSONObject JO = jsonArray.getJSONObject(count);
_id = JO.getInt("id");
_doctorname = JO.getString("doctorname");
_doclat = JO.getString("latitude");
_doclong = JO.getString("longitude");
count++;
Double d = Double.parseDouble(_doclat);
Double e = Double.parseDouble(_doclong);
LatLng latLng = new LatLng(d,e);
//mMap = googleMap;
MarkerOptions _markeroptions = new MarkerOptions()
.position(latLng);
mMap.addMarker(_markeroptions);
}
}
catch (JSONException e) {
e.printStackTrace();
mMap = googleMap;
mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
//Initialize Google Play Services
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
buildGoogleApiClient();
mMap.setMyLocationEnabled(true);
}
}
else {
buildGoogleApiClient();
mMap.setMyLocationEnabled(true);
}
// int a = _st.json_string.length();
// Add a marker in Sydney and move the camera
//LatLng sydney = new LatLng(-34, 151);
//mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney"));
//mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));
}
}
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mGoogleApiClient.connect();
}
#Override
public void onConnected(#Nullable Bundle bundle) {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(1000);
mLocationRequest.setFastestInterval(1000);
mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
}
#Override
public void onConnectionSuspended(int i) {
}
#Override
public void onLocationChanged(Location location) {
mLastLocation = location;
if (mCurrLocationMarker != null) {
mCurrLocationMarker.remove();
}
//Place current location marker
LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title("Current Position");
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
mCurrLocationMarker = mMap.addMarker(markerOptions);
//move map camera
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
mMap.animateCamera(CameraUpdateFactory.zoomTo(11));
//stop location updates
if (mGoogleApiClient != null) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
}
//ParseJSONdata parseJSONdata = new ParseJSONdata();
}
#Override
public void onConnectionFailed(#NonNull ConnectionResult connectionResult) {
}
public boolean checkLocationPermission(){
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
// Asking user if explanation is needed
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.ACCESS_FINE_LOCATION)) {
// Show an expanation to the user *asynchronously* -- don't block
// this thread waiting for the user's response! After the user
// sees the explanation, try again to request the permission.
//Prompt the user once explanation has been shown
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION);
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION);
}
return false;
} else {
return true;
}
}
#Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_LOCATION: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// Permission was granted.
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
if (mGoogleApiClient == null) {
buildGoogleApiClient();
}
mMap.setMyLocationEnabled(true);
}
} else {
// Permission denied, Disable the functionality that depends on this permission.
Toast.makeText(this, "permission denied", Toast.LENGTH_LONG).show();
}
return;
}
// other 'case' lines to check for other permissions this app might request.
//You can add here other case statements according to your requirement.
}
}

When onMapReady() method is call you used map Object without initialization and after you initialize, so then have return null pointer.
mMap = googleMap; //Map initialize by this line
mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
//Initialize Google Play Services
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
buildGoogleApiClient();
mMap.setMyLocationEnabled(true);
}
}
else {
buildGoogleApiClient();
mMap.setMyLocationEnabled(true);
}
this code put above try catch in onMapReady() method and run your code.

Android mapping activity does not follow user or display location layer [duplicate]

I want google maps to show the location of the user. I tried this code, but it did not work on Android 6.
private GoogleMap map;
LocationManager lm;
LocationListener ll;
Location l;
LatLng pos;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.start_layout);
lm = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
ll = new LocationListener() {
#Override
public void onLocationChanged(Location location) {
l = (Location) location;
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {}
#Override
public void onProviderEnabled(String provider) {}
#Override
public void onProviderDisabled(String provider) {}
};
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.nMap);
mapFragment.getMapAsync(this);
}
#Override
public void onMapReady(GoogleMap googleMap) {
map = googleMap;
if(ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
lm.requestLocationUpdates(lm.NETWORK_PROVIDER, 0, 0, ll);
}
pos = new LatLng(l.getLatitude(), l.getLongitude());
// Add a marker in Sydney and move the camera
map.setMyLocationEnabled(true);
map.addMarker(new MarkerOptions().position(pos).title("Marker in Sydney"));
map.moveCamera(CameraUpdateFactory.newLatLng(pos));
}
Here are the permissions I've set:
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />

For using FusedLocationProviderClient with Google Play Services 11 and higher:
see here:
How to get current Location in GoogleMap using FusedLocationProviderClient
For using (now deprecated) FusedLocationProviderApi:
If your project uses Google Play Services 10 or lower, using the FusedLocationProviderApi is the optimal choice.
The FusedLocationProviderApi offers less battery drain than the old open source LocationManager API.
Also, if you're already using Google Play Services for Google Maps, there's no reason not to use it.
Here is a full Activity class that places a Marker at the current location, and also moves the camera to the current position.
It also checks for the Location permission at runtime for Android 6 and later (Marshmallow, Nougat, Oreo).
In order to properly handle the Location permission runtime check that is necessary on Android M/Android 6 and later, you need to ensure that the user has granted your app the Location permission before calling mGoogleMap.setMyLocationEnabled(true) and also before requesting location updates.
public class MapLocationActivity extends AppCompatActivity
implements OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
GoogleMap mGoogleMap;
SupportMapFragment mapFrag;
LocationRequest mLocationRequest;
GoogleApiClient mGoogleApiClient;
Location mLastLocation;
Marker mCurrLocationMarker;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getSupportActionBar().setTitle("Map Location Activity");
mapFrag = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
mapFrag.getMapAsync(this);
}
#Override
public void onPause() {
super.onPause();
//stop location updates when Activity is no longer active
if (mGoogleApiClient != null) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
}
}
#Override
public void onMapReady(GoogleMap googleMap)
{
mGoogleMap=googleMap;
mGoogleMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
//Initialize Google Play Services
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
//Location Permission already granted
buildGoogleApiClient();
mGoogleMap.setMyLocationEnabled(true);
} else {
//Request Location Permission
checkLocationPermission();
}
}
else {
buildGoogleApiClient();
mGoogleMap.setMyLocationEnabled(true);
}
}
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mGoogleApiClient.connect();
}
#Override
public void onConnected(Bundle bundle) {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(1000);
mLocationRequest.setFastestInterval(1000);
mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
}
#Override
public void onConnectionSuspended(int i) {}
#Override
public void onConnectionFailed(ConnectionResult connectionResult) {}
#Override
public void onLocationChanged(Location location)
{
mLastLocation = location;
if (mCurrLocationMarker != null) {
mCurrLocationMarker.remove();
}
//Place current location marker
LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title("Current Position");
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
mCurrLocationMarker = mGoogleMap.addMarker(markerOptions);
//move map camera
mGoogleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng,11));
}
public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
private void checkLocationPermission() {
if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
// Should we show an explanation?
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.ACCESS_FINE_LOCATION)) {
// Show an explanation to the user *asynchronously* -- don't block
// this thread waiting for the user's response! After the user
// sees the explanation, try again to request the permission.
new AlertDialog.Builder(this)
.setTitle("Location Permission Needed")
.setMessage("This app needs the Location permission, please accept to use location functionality")
.setPositiveButton("OK", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
//Prompt the user once explanation has been shown
ActivityCompat.requestPermissions(MapLocationActivity.this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION );
}
})
.create()
.show();
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION );
}
}
}
#Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_LOCATION: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// permission was granted, yay! Do the
// location-related task you need to do.
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
if (mGoogleApiClient == null) {
buildGoogleApiClient();
}
mGoogleMap.setMyLocationEnabled(true);
}
} else {
// permission denied, boo! Disable the
// functionality that depends on this permission.
Toast.makeText(this, "permission denied", Toast.LENGTH_LONG).show();
}
return;
}
// other 'case' lines to check for other
// permissions this app might request
}
}
}
activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:map="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/map"
tools:context=".MapLocationActivity"
android:name="com.google.android.gms.maps.SupportMapFragment"/>
</LinearLayout>
Result:
Show permission explanation if needed using an AlertDialog (this happens if the user denies a permission request, or grants the permission and then later revokes it in the settings):
Prompt the user for Location permission by calling ActivityCompat.requestPermissions():
Move camera to current location and place Marker when the Location permission is granted:

Sorry but that's just much too much overhead (above), short and quick, if you have the MapFragment, you also have to map, just do the following:
if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
googleMap.setMyLocationEnabled(true)
} else {
// Show rationale and request permission.
}
Code is in Kotlin, hope you don't mind.
have fun
Btw I think this one is a duplicate of: Show Current Location inside Google Map Fragment

Firstly make sure your API Key is valid and add this into your manifest <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
Here's my maps activity.. there might be some redundant information in it since it's from a larger project I created.
import android.content.Intent;
import android.content.IntentSender;
import android.location.Location;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
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.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
public class MapsActivity extends FragmentActivity implements
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
//These variable are initalized here as they need to be used in more than one methid
private double currentLatitude; //lat of user
private double currentLongitude; //long of user
private double latitudeVillageApartmets= 53.385952001750184;
private double longitudeVillageApartments= -6.599087119102478;
public static final String TAG = MapsActivity.class.getSimpleName();
private final static int CONNECTION_FAILURE_RESOLUTION_REQUEST = 9000;
private GoogleMap mMap; // Might be null if Google Play services APK is not available.
private GoogleApiClient mGoogleApiClient;
private LocationRequest mLocationRequest;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
setUpMapIfNeeded();
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
// Create the LocationRequest object
mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(10 * 1000) // 10 seconds, in milliseconds
.setFastestInterval(1 * 1000); // 1 second, in milliseconds
}
/*These methods all have to do with the map and wht happens if the activity is paused etc*/
//contains lat and lon of another marker
private void setUpMap() {
MarkerOptions marker = new MarkerOptions().position(new LatLng(latitudeVillageApartmets, longitudeVillageApartments)).title("1"); //create marker
mMap.addMarker(marker); // adding marker
}
//contains your lat and lon
private void handleNewLocation(Location location) {
Log.d(TAG, location.toString());
currentLatitude = location.getLatitude();
currentLongitude = location.getLongitude();
LatLng latLng = new LatLng(currentLatitude, currentLongitude);
MarkerOptions options = new MarkerOptions()
.position(latLng)
.title("You are here");
mMap.addMarker(options);
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom((latLng), 11.0F));
}
#Override
protected void onResume() {
super.onResume();
setUpMapIfNeeded();
mGoogleApiClient.connect();
}
#Override
protected void onPause() {
super.onPause();
if (mGoogleApiClient.isConnected()) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
mGoogleApiClient.disconnect();
}
}
private void setUpMapIfNeeded() {
// Do a null check to confirm that we have not already instantiated the map.
if (mMap == null) {
// Try to obtain the map from the SupportMapFragment.
mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map))
.getMap();
// Check if we were successful in obtaining the map.
if (mMap != null) {
setUpMap();
}
}
}
#Override
public void onConnected(Bundle bundle) {
Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if (location == null) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
else {
handleNewLocation(location);
}
}
#Override
public void onConnectionSuspended(int i) {
}
#Override
public void onConnectionFailed(ConnectionResult connectionResult) {
if (connectionResult.hasResolution()) {
try {
// Start an Activity that tries to resolve the error
connectionResult.startResolutionForResult(this, CONNECTION_FAILURE_RESOLUTION_REQUEST);
/*
* Thrown if Google Play services canceled the original
* PendingIntent
*/
} catch (IntentSender.SendIntentException e) {
// Log the error
e.printStackTrace();
}
} else {
/*
* If no resolution is available, display a dialog to the
* user with the error.
*/
Log.i(TAG, "Location services connection failed with code " + connectionResult.getErrorCode());
}
}
#Override
public void onLocationChanged(Location location) {
handleNewLocation(location);
}
}
There's a lot of methods here that are hard to understand but basically all update the map when it's paused etc. There are also connection timeouts etc. Sorry for just posting this, I tried to fix your code but I couldn't figure out what was wrong.