Develop Reference

Getting user location takes a very long time inside Google Map FragmentActivity

I am having issues getting a location in my map activity. Basically, it gets the location, but takes a VERY long time (a few minutes). I'm using a singleton that requests a single location update to retrieve my location. This works fine across multiple other instances in my app. However when I try it in my map activity, it takes a very long time. Here is my class I use to get a location:
public class SingleShotLocationProvider {
public interface LocationCallback {
void onNewLocationAvailable(GPSCoordinates location);
}
public static void requestSingleUpdate(final Context context, final LocationCallback callback) {
final LocationManager locationManager = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
//If network is available
if (locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)) {
Log.i("SingleShot", "network available");
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_COARSE);
try {
locationManager.requestSingleUpdate(criteria, new LocationListener() {
#Override
public void onLocationChanged(Location location) {
callback.onNewLocationAvailable(new GPSCoordinates(location.getLongitude(), location.getLatitude()));
}
#Override public void onStatusChanged(String provider, int status, Bundle extras) {}
#Override public void onProviderEnabled(String provider) {}
#Override public void onProviderDisabled(String provider) {}
}, null);
}
catch (SecurityException e){
Log.e("Location", "security exception");
}
}
//If GPS is enabled
else if (locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)){
Log.i("SingleShot", "GPS available");
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
try {
locationManager.requestSingleUpdate(criteria, new LocationListener() {
#Override
public void onLocationChanged(Location location) {
callback.onNewLocationAvailable(new GPSCoordinates(location.getLongitude(), location.getLatitude()));
}
#Override public void onStatusChanged(String provider, int status, Bundle extras) {}
#Override public void onProviderEnabled(String provider) {}
#Override public void onProviderDisabled(String provider) {}
}, null);
}
catch (SecurityException e){
Log.e("SingleShot", "security exception");
}
}
else{
Toast.makeText(context, "No network or GPS available. Try again later.", Toast.LENGTH_LONG).show();
}
}
public static class GPSCoordinates {
public float longitude = -1;
public float latitude = -1;
public GPSCoordinates(double lon, double lat) {
longitude = (float) lon;
latitude = (float) lat;
}
}
}
This class works well in most areas in my app. It works in services and fragments. However when I use it in my map activity (FragmentActivity), the singleton takes a long time to use the callback I send it . Here is how I am requesting a new location from my map activity:
public class Traffic extends FragmentActivity
implements OnMapReadyCallback {
MapFragment mapFragment;
GoogleMap map;
//...
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_map);
mapFragment = (MapFragment) getFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
//...
}
#Override
public void onMapReady(GoogleMap googleMap) {
map = googleMap;
map.setMapType(GoogleMap.MAP_TYPE_NORMAL);
SingleShotLocationProvider.requestSingleUpdate(getApplicationContext(), new SingleShotLocationProvider.LocationCallback() {
#Override
public void onNewLocationAvailable(SingleShotLocationProvider.GPSCoordinates location) {
Log.i(TAG, location.toString());
}
});
}
}
Any thoughts on why this would be taking so long?

Try changing the Criteria to COARSE or something which is less accurate but adequate.
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_COARSE);
https://developer.android.com/reference/android/location/Criteria.html

Get GPS location in AsyncTask

I have an AsyncTask class that needs to get user's location when this AsyncTask is called.
The idea is to check if location service is enabled or not, if not, the location service toggle will popup for user to turn it on, then it will go back to the task to continue getting the location and finish the job.
However, the code below show NullPointerException on the line lat = location.getLatitude(); near the end of onPreExecute(). They said because getLastKnownLocation gets nothing as it's just been turned on a moment ago, then how can I get the location right after the location service has been turned on?
LocationManager locationManager;
LocationListener locationListener;
double lat;
double longi;
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
}
#Override
protected void onPreExecute() {
super.onPreExecute();
location = new Location(LocationManager.NETWORK_PROVIDER);
locationManager = (LocationManager) context.getSystemService(context.LOCATION_SERVICE);
if (!locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
context.startActivity(intent);
}
//I copy the part below from the internet but seems like "onProviderDisabled" and "onLocationChanged" were never be called
locationListener = new LocationListener() {
#Override
public void onLocationChanged(Location location) {
Log.v("GPS CHECKKKKKKK",location.getLatitude()+"_"+location.getLongitude());
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onProviderDisabled(String provider) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
context.startActivity(intent);
}
};
locationManager.requestLocationUpdates("gps", 500, 0, locationListener);
location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
//locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER,5000,0, locationListener);
lat = location.getLatitude();
longi= location.getLongitude();
Log.v("GPS Cord CHECK",lat+"_"+longi);
}
#Override
protected String doInBackground(final Checkout_Package... params) {
//Doing the job that needs lat and longi value!
}
Thank you for your time!

You cannot create and put a location listener in onPreExecute() because the onChanged handlers will only be invoked much later when onPostExecute or even your AsyncTask has finished.
What you should do instead is start an AsyncTask in that location changed handler.
So in onLocationChanged().

With greenapps's suggest I figured it out. I put the code into the button that call the AsyncTask
checkout_btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
LocationManager locationManager;
LocationListener locationListener;
gotit = false; //Boolean to start the AsyncTask only once.
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
locationListener = new LocationListener() {
#Override
public void onLocationChanged(Location location) {
Log.v("GPS CHECKKKKKKK",location.getLatitude()+"_"+location.getLongitude());
lat = location.getLatitude();
longi = location.getLongitude();
if (gotit == false) {
new Checkout_Async(Checkout.this, listener).execute(new Checkout_Package(user, product_all, getTotalCost(product_all), fee, getTotalCost(product_all) + fee, lat, longi));
gotit = true;
pd.dismiss();
}
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onProviderDisabled(String provider) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(intent);
}
};
pd=ProgressDialog.show(Checkout.this,"",getResources().getString(R.string.please_wait),false);
locationManager.requestLocationUpdates("gps",50,0,locationListener);
}
});
Now it works. Thank you!

I have integrated google map. but marker updated very late .i update the marker on the response of google direction api

I have integrated google map. But marker updated very late. I update the marker on the response of google direction API

call this method from onCreate(), i hope this will help you.
public void setUpMap()
{
final LocationManager lm = (LocationManager) getSystemService(LOCATION_SERVICE);
locationListener = new LocationListener() {
#Override
public void onLocationChanged(Location location) {
position = new LatLng(location.getLatitude(),location.getLongitude());
mMap.addMarker(new MarkerOptions().position(position)).setIcon(BitmapDescriptorFactory.fromResource(R.drawable.emp2));
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(position, 9));
lm.removeUpdates(locationListener);
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras)
{
}
#Override
public void onProviderEnabled(String provider)
{
}
#Override
public void onProviderDisabled(String provider)
{
}
};
lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);

Arcgis : how to get device location

Hie i tried to implement this codes in my application but it doesnt work , i dont know where i went wrong.
basically, when i launch the sample of the device location. it doesnt show me where is my current location and i dont see any blue dots that resembles the current location i am at.
the only thing that i see is the map . just a plain zoom out map.
I would be really thankful if someone who could help me out on how to get the current location with the blue dots that is displayed on the map..
this is my MainActivity.class
public class HelloWorld extends Activity {
MapView mMapView = null;
ArcGISTiledMapServiceLayer tileLayer;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Retrieve the map and initial extent from XML layout
mMapView = (MapView) findViewById(R.id.map);
mMapView.addLayer(new ArcGISTiledMapServiceLayer(
"http://services.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer"));
mMapView.setOnStatusChangedListener(new OnStatusChangedListener() {
public void onStatusChanged(Object source, STATUS status) {
if (source == mMapView && status == STATUS.INITIALIZED) {
LocationService ls = mMapView.getLocationService();
ls.setAutoPan(false);
ls.start();
}
}
});
}
protected void onPause() {
super.onPause();
mMapView.pause();
}
#Override
protected void onResume() {
super.onResume();
mMapView.unpause();
}
}

this is a code that draws my location every 1 second via provider and GPS .
let's first declare variables :
private GraphicsLayer myGraphicalLayer;
MapView mMapView;
ArcGISLocalTiledLayer baseLayer;
private LocationManager mlocManager;
private LocationListener mlocListener;
in onCreate function WE CALL LocationListener:
mlocManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
mlocListener = new MyLocationListener();
mlocManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000, 0, mlocListener);
mlocManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 1000, 0, mlocListener);
// loading the map
mMapView = (MapView) findViewById(R.id.localMap);
baseLayer = new ArcGISLocalTiledLayer(basemapurl);
mMapView.addLayer(baseLayer);
// defining my position layer
myGraphicalLayer = new GraphicsLayer();
then a function to draw my location :
private void SetMyLocationPoint(final double x, final double y) {
PictureMarkerSymbol myPin = new PictureMarkerSymbol(getResources().getDrawable(
R.drawable.mylocation_icon));
Point wgspoint = new Point(x, y);
Point mapPoint = (Point) GeometryEngine.project(wgspoint, SpatialReference.create(4326),
mMapView.getSpatialReference());
Graphic myPinGraphic = new Graphic(mapPoint, myPin);
try {
myGraphicalLayer.removeAll();
} catch (Exception e) {
e.printStackTrace();
}
myGraphicalLayer.addGraphic(myPinGraphic);
myGraphicalLayer.setVisible(true);
mMapView.addLayer(myGraphicalLayer);
}
make internal class that implements MyLocationListener to get you instant location, and let it call the function named SetMyLocationPoint like this way :
public class MyLocationListener implements LocationListener {
#Override
public void onLocationChanged(Location loc) {
SetMyLocationPoint(loc.getLongitude(), loc.getLatitude());
}
#Override
public void onProviderDisabled(String provider) {
Toast.makeText(getApplicationContext(), "provider enabled", Toast.LENGTH_SHORT)
.show();
}
#Override
public void onProviderEnabled(String provider) {
Toast.makeText(getApplicationContext(), "provider disabled", Toast.LENGTH_SHORT)
.show();
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
}

You need to use your own location manager or the location client to get the device's current location and then you will have to add that point on the map.
Your map should be in a MapFragment.
Get the googleMap object from the fragment and then add your custom blue dot on it.
LocationManager locationManager = (LocationManager) getApplicationContext()
.getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,
5000, 5, listener);
}
private LocationListener listener = new LocationListener() {
#Override
public void onLocationChanged(Location location) {
// TODO Auto-generated method stub
Log.e("Google", "Location Changed");
if (location == null)
return;
Log.e("latitude", location.getLatitude() + "");
Log.e("longitude", location.getLongitude() + "");
}
}
#Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
#Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
};
The above code gets you the location in onLocationChanged method.
Note: i have used GPS_PROVIDER to get the location.
There are other ways to get the current location too.

LocationListener InSide AsyncTask

Hi I am New to android programming and currently developing an application that uses location manager to get user location and place a marker on a map. i am attempting to use AsyncTask to run the LocationListener and Constantly update the marker when the user location has changed.
this is the class i am working on...
public class IncidentActivity extends MapActivity{
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
this.setContentView(R.layout.incidentactivity);
mapView = (MapView)findViewById(R.id.mapView);
mapView.setBuiltInZoomControls(true);
mapView.setTraffic(true);
mapController = mapView.getController();
String coordinates[] = {"-26.167004","27.965505"};
double lat = Double.parseDouble(coordinates[0]);
double lng = Double.parseDouble(coordinates[1]);
geoPoint = new GeoPoint((int)(lat*1E6), (int)(lng*1E6));
mapController.animateTo(geoPoint);
mapController.setZoom(16);
mapView.invalidate();
new MyLocationAsyncTask().execute();
}
private class MyLocationAsyncTask extends AsyncTask<Void, Location, Void> implements LocationListener{
private double latLocation;
private Location l;
//location management variables to track and maintain user location
protected LocationManager locationManager;
protected LocationListener locationListener;
#Override
protected Void doInBackground(Void... arg0) {
Looper.prepare();
locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 1, locationListener);
this.publishProgress(l);
return null;
}
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
}
#Override
protected void onProgressUpdate(Location... values) {
super.onProgressUpdate(values);
}
//this method is never executed i dont know why...?
public void onLocationChanged(Location location) {
if (location != null){
latLocation = location.getLatitude();
Toast.makeText(getBaseContext(), " Your latLocation :" + latLocation, Toast.LENGTH_LONG).show();
//Log.d("Your Location", ""+latLocation);
}
}
public void onProviderDisabled(String provider) {
}
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
}
}

I've just implemented such AsyncTask:
class GetPositionTask extends AsyncTask<Void, Void, Location> implements LocationListener
{
final long TWO_MINUTES = 2*60*1000;
private Location location;
private LocationManager lm;
protected void onPreExecute()
{
// Configure location manager - I'm using just the network provider in this example
lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 1000, 0, this);
nearProgress.setVisibility(View.VISIBLE);
}
protected Location doInBackground(Void... params)
{
// Try to use the last known position
Location lastLocation = lm.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
// If it's too old, get a new one by location manager
if (System.currentTimeMillis() - lastLocation.getTime() > TWO_MINUTES)
{
while (location == null)
try { Thread.sleep(100); } catch (Exception ex) {}
return location;
}
return lastLocation;
}
protected void onPostExecute(Location location)
{
nearProgress.setVisibility(View.GONE);
lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
lm.removeUpdates(this);
// HERE USE THE LOCATION
}
#Override
public void onLocationChanged(Location newLocation)
{
location = newLocation;
}
public void onProviderDisabled(String provider) {}
public void onProviderEnabled(String provider) {}
public void onStatusChanged(String provider, int status, Bundle extras) {}
}

From what I have read and tried, you cannot use a looper (which is needed by the locationlistener), inside an ASyncTask. Click Here
Actually it mean the two threading models are not compatible, so you can't
use these together. Looper expects to to own the thread that you associate
it with, while AsyncTask owns the thread it creates for you to run in the
background. They thus conflict with each other, and can't be used together.
Dianne Hackborn suggested using a HandlerThread, but I succeeded in getting mine to work inside of an IntentService. I will admit that my code is still a bit of a hack.