What is the simplest and most robust way to get the user's current location in Android?
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What is the simplest and most robust way to get the user's current location in Android?
The LocationManager API in android seems like it's a bit of a pain to use for an application that only needs an occasional and rough approximation of the user's location.
The app I'm working on isn't really a location app per se, but it does need to get the user's location in order to display a list of nearby businesses. It doesn't need to worry about if the user is moving around or anything like that.
Here's what I'd like to do:
- Show the user a list of nearby locations.
- Preload the user's location so that by the time I need it in
ActivityX, it will be available. - Don't particularly care about accuracy or frequency of update. Just grabbing one location is sufficient as long as it's not way off. Maybe if I want to be fancy I'll update the location once every few mins or so, but it's not a huge priority.
- Work for any device as long as it has either a GPS or a Network Location provider.
It seems like it shouldn't be that hard, but it appears to me that I have to spin up two different location providers (GPS and NETWORK) and manage each's lifecycle. Not only that, but I have to duplicate the same code in multiple activities to satisfy #2. I've tried using getBestProvider() in the past to cut the solution down to just using one location provider, but that seems to only give you the best "theoretical" provider rather than the provider that's actually going to give you the best results.
Is there a simpler way to accomplish this?
Answer by Robby Pond for What is the simplest and most robust way to get the user's current location in Android?
You could always just use LocationManager.getLastKnownLocation() but like it says it could be out of date.
And a simple way to get a general location could be registering for the network (usually pretty fast).
LocationManager locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE); locationManager.requestLocationUpdates( LocationManager.NETWORK_PROVIDER, 1000, 1000, this); and then doing
locationManager.removeUpdates(this); in the onLocationChanged() method of the listener.
Answer by npinti for What is the simplest and most robust way to get the user's current location in Android?
I am not sure if the Location-Based Services can get the location from other infrastructures other than GPS, but according to that article, it does seem possible:
Applications can call on any of several types of positioning methods.
Using the mobile phone network: The current cell ID can be used to identify the Base Transceiver Station (BTS) that the device is communicating with and the location of that BTS. Clearly, the accuracy of this method depends on the size of the cell, and can be quite inaccurate. A GSM cell may be anywhere from 2 to 20 kilometers in diameter. Other techniques used along with cell ID can achieve accuracy within 150 meters.
Using satellites: The Global Positioning System (GPS), controlled by the US Department of Defense, uses a constellation of 24 satellites orbiting the earth. GPS determines the device's position by calculating differences in the times signals from different satellites take to reach the receiver. GPS signals are encoded, so the mobile device must be equipped with a GPS receiver. GPS is potentially the most accurate method (between 4 and 40 meters if the GPS receiver has a clear view of the sky), but it has some drawbacks: The extra hardware can be costly, consumes battery while in use, and requires some warm-up after a cold start to get an initial fix on visible satellites. It also suffers from "canyon effects" in cities, where satellite visibility is intermittent.
Using short-range positioning beacons: In relatively small areas, such as a single building, a local area network can provide locations along with other services. For example, appropriately equipped devices can use Bluetooth for short-range positioning.
Answer by Fedor for What is the simplest and most robust way to get the user's current location in Android?
Here's what I do:
- First of all I check what providers are enabled. Some may be disabled on the device, some may be disabled in application manifest.
- If any provider is available I start location listeners and timeout timer. It's 20 seconds in my example, may not be enough for GPS so you can enlarge it.
- If I get update from location listener I use the provided value. I stop listeners and timer.
- If I don't get any updates and timer elapses I have to use last known values.
- I grab last known values from available providers and choose the most recent of them.
Here's how I use my class:
LocationResult locationResult = new LocationResult(){ @Override public void gotLocation(Location location){ //Got the location! } }; MyLocation myLocation = new MyLocation(); myLocation.getLocation(this, locationResult); And here's MyLocation class:
import java.util.Timer; import java.util.TimerTask; import android.content.Context; import android.location.Location; import android.location.LocationListener; import android.location.LocationManager; import android.os.Bundle; public class MyLocation { Timer timer1; LocationManager lm; LocationResult locationResult; boolean gps_enabled=false; boolean network_enabled=false; public boolean getLocation(Context context, LocationResult result) { //I use LocationResult callback class to pass location value from MyLocation to user code. locationResult=result; if(lm==null) lm = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE); //exceptions will be thrown if provider is not permitted. try{gps_enabled=lm.isProviderEnabled(LocationManager.GPS_PROVIDER);}catch(Exception ex){} try{network_enabled=lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);}catch(Exception ex){} //don't start listeners if no provider is enabled if(!gps_enabled && !network_enabled) return false; if(gps_enabled) lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps); if(network_enabled) lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListenerNetwork); timer1=new Timer(); timer1.schedule(new GetLastLocation(), 20000); return true; } LocationListener locationListenerGps = new LocationListener() { public void onLocationChanged(Location location) { timer1.cancel(); locationResult.gotLocation(location); lm.removeUpdates(this); lm.removeUpdates(locationListenerNetwork); } public void onProviderDisabled(String provider) {} public void onProviderEnabled(String provider) {} public void onStatusChanged(String provider, int status, Bundle extras) {} }; LocationListener locationListenerNetwork = new LocationListener() { public void onLocationChanged(Location location) { timer1.cancel(); locationResult.gotLocation(location); lm.removeUpdates(this); lm.removeUpdates(locationListenerGps); } public void onProviderDisabled(String provider) {} public void onProviderEnabled(String provider) {} public void onStatusChanged(String provider, int status, Bundle extras) {} }; class GetLastLocation extends TimerTask { @Override public void run() { lm.removeUpdates(locationListenerGps); lm.removeUpdates(locationListenerNetwork); Location net_loc=null, gps_loc=null; if(gps_enabled) gps_loc=lm.getLastKnownLocation(LocationManager.GPS_PROVIDER); if(network_enabled) net_loc=lm.getLastKnownLocation(LocationManager.NETWORK_PROVIDER); //if there are both values use the latest one if(gps_loc!=null && net_loc!=null){ if(gps_loc.getTime()>net_loc.getTime()) locationResult.gotLocation(gps_loc); else locationResult.gotLocation(net_loc); return; } if(gps_loc!=null){ locationResult.gotLocation(gps_loc); return; } if(net_loc!=null){ locationResult.gotLocation(net_loc); return; } locationResult.gotLocation(null); } } public static abstract class LocationResult{ public abstract void gotLocation(Location location); } } Somebody may also want to modify my logic. For example if you get update from Network provider don't stop listeners but continue waiting. GPS gives more accurate data so it's worth waiting for it. If timer elapses and you've got update from Network but not from GPS then you can use value provided from Network.
One more approach is to use LocationClient http://developer.android.com/training/location/retrieve-current.html. But it requires Google Play Services apk to be installed on user device.
Answer by Jhon for What is the simplest and most robust way to get the user's current location in Android?
Actualy we can use the two providers both. And they just share a public listener:
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 10 * 1000, (float) 10.0, listener); locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 90 * 1000, (float) 10.0, listener); This is necessary because the OnLocationChanged() method always need to be called in time.
Answer by Lyudmil for What is the simplest and most robust way to get the user's current location in Android?
To get and show the user's current location, you could also use MyLocationOverlay. Suppose you have a mapView field in your activity. All you would need to do to show the user location is the following:
myLocationOverlay = new MyLocationOverlay(this, mapView); myLocationOverlay.enableMyLocation(); mapView.getOverlays().add(myLocationOverlay); This gets the current location from either the GPS or the network. If both fail, enableMyLocation() will return false.
As for the locations of things around the area, an ItemizedOverlay should do the trick.
I hope I haven't misunderstood your question. Good luck.
Answer by Ariel Malka for What is the simplest and most robust way to get the user's current location in Android?
"Obtaining User Location" from Google itself is definitely the reference regarding GPS:
http://developer.android.com/guide/topics/location/obtaining-user-location.html
Answer by wormhit for What is the simplest and most robust way to get the user's current location in Android?
After searching for best implementation how to get best precise user location I managed to combine all the best methods and come up with following class:
/** * Retrieve accurate location from GPS or network services. * * * Class usage example: * * public void onCreate(Bundle savedInstanceState) { * ... * my_location = new MyLocation(); * my_location.init(main.this, locationResult); * } * * * public LocationResult locationResult = new LocationResult(){ * @Override * public void gotLocation(final Location location){ * // do something * location.getLongitude(); * location.getLatitude(); * } * }; */ class MyLocation{ /** * If GPS is enabled. * Use minimal connected satellites count. */ private static final int min_gps_sat_count = 5; /** * Iteration step time. */ private static final int iteration_timeout_step = 500; LocationResult locationResult; private Location bestLocation = null; private Handler handler = new Handler(); private LocationManager myLocationManager; public Context context; private boolean gps_enabled = false; private int counts = 0; private int sat_count = 0; private Runnable showTime = new Runnable() { public void run() { boolean stop = false; counts++; System.println("counts=" + counts); //if timeout (1 min) exceeded, stop tying if(counts > 120){ stop = true; } //update last best location bestLocation = getLocation(context); //if location is not ready or don`t exists, try again if(bestLocation == null && gps_enabled){ System.println("BestLocation not ready, continue to wait"); handler.postDelayed(this, iteration_timeout_step); }else{ //if best location is known, calculate if we need to continue to look for better location //if gps is enabled and min satellites count has not been connected or min check count is smaller then 4 (2 sec) if(stop == false && !needToStop()){ System.println("Connected " + sat_count + " sattelites. continue waiting.."); handler.postDelayed(this, iteration_timeout_step); }else{ System.println("#########################################"); System.println("BestLocation finded return result to main. sat_count=" + sat_count); System.println("#########################################"); // removing all updates and listeners myLocationManager.removeUpdates(gpsLocationListener); myLocationManager.removeUpdates(networkLocationListener); myLocationManager.removeGpsStatusListener(gpsStatusListener); sat_count = 0; // send best location to locationResult locationResult.gotLocation(bestLocation); } } } }; /** * Determine if continue to try to find best location */ private Boolean needToStop(){ if(!gps_enabled){ return true; } else if(counts <= 4){ return false; } if(sat_count < min_gps_sat_count){ //if 20-25 sec and 3 satellites found then stop if(counts >= 40 && sat_count >= 3){ return true; } return false; } } return true; } /** * Best location abstract result class */ public static abstract class LocationResult{ public abstract void gotLocation(Location location); } /** * Initialize starting values and starting best location listeners * * @param Context ctx * @param LocationResult result */ public void init(Context ctx, LocationResult result){ context = ctx; locationResult = result; myLocationManager = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE); gps_enabled = (Boolean) myLocationManager.isProviderEnabled(LocationManager.GPS_PROVIDER); bestLocation = null; counts = 0; // turning on location updates myLocationManager.requestLocationUpdates("network", 0, 0, networkLocationListener); myLocationManager.requestLocationUpdates("gps", 0, 0, gpsLocationListener); myLocationManager.addGpsStatusListener(gpsStatusListener); // starting best location finder loop handler.postDelayed(showTime, iteration_timeout_step); } /** * GpsStatus listener. OnChainged counts connected satellites count. */ public final GpsStatus.Listener gpsStatusListener = new GpsStatus.Listener() { public void onGpsStatusChanged(int event) { if(event == GpsStatus.GPS_EVENT_SATELLITE_STATUS){ try { // Check number of satellites in list to determine fix state GpsStatus status = myLocationManager.getGpsStatus(null); Iterablesatellites = status.getSatellites(); sat_count = 0; IteratorsatI = satellites.iterator(); while(satI.hasNext()) { GpsSatellite satellite = satI.next(); System.println("Satellite: snr=" + satellite.getSnr() + ", elevation=" + satellite.getElevation()); sat_count++; } } catch (Exception e) { e.printStackTrace(); sat_count = min_gps_sat_count + 1; } System.println("#### sat_count = " + sat_count); } } }; /** * Gps location listener. */ public final LocationListener gpsLocationListener = new LocationListener(){ @Override public void onLocationChanged(Location location){ } public void onProviderDisabled(String provider){} public void onProviderEnabled(String provider){} public void onStatusChanged(String provider, int status, Bundle extras){} }; /** * Network location listener. */ public final LocationListener networkLocationListener = new LocationListener(){ @Override public void onLocationChanged(Location location){ } public void onProviderDisabled(String provider){} public void onProviderEnabled(String provider){} public void onStatusChanged(String provider, int status, Bundle extras){} }; /** * Returns best location using LocationManager.getBestProvider() * * @param context * @return Location|null */ public static Location getLocation(Context context){ System.println("getLocation()"); // fetch last known location and update it try { LocationManager lm = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE); Criteria criteria = new Criteria(); criteria.setAccuracy(Criteria.ACCURACY_FINE); criteria.setAltitudeRequired(false); criteria.setBearingRequired(false); criteria.setCostAllowed(true); String strLocationProvider = lm.getBestProvider(criteria, true); System.println("strLocationProvider=" + strLocationProvider); Location location = lm.getLastKnownLocation(strLocationProvider); if(location != null){ return location; } return null; } catch (Exception e) { e.printStackTrace(); return null; } } } This class tries to connect to min_gps_sat_count satellites if GPS is enabled. Else returns LocationManager.getBestProvider() location. Check the code!
Answer by differenziale for What is the simplest and most robust way to get the user's current location in Android?
With Fedor's solution I've experienced multiple execution of the callback gotLocation. It seems to be due to a race condition in the overridden LocationListener.onLocationChanged method, when gotLocation method is 'long enough'. I'm not sure, but I guess removeUpdates prevents the enqueueing of new messages in the Looper queue, but it doesn't remove those already enqueued but not yet consumed. Hence the race condition.
To reduce the probability of this wrong behavior it's possible to call removeUpdates before firing the onLocationChanged event, but still we have the race condition.
The best solution I found is to replace requestLocationUpdates with requestSingleUpdate.
This is my version, based on Fedor's solution, using an Handler to send a message to the looper thread:
public class LocationResolver { private Timer timer; private LocationManager locationManager; private LocationResult locationResult; private boolean gpsEnabled = false; private boolean networkEnabled = false; private Handler locationTimeoutHandler; private final Callback locationTimeoutCallback = new Callback() { public boolean handleMessage(Message msg) { locationTimeoutFunc(); return true; } private void locationTimeoutFunc() { locationManager.removeUpdates(locationListenerGps); locationManager.removeUpdates(locationListenerNetwork); Location networkLocation = null, gpsLocation = null; if (gpsEnabled) gpsLocation = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER); if (networkEnabled) networkLocation = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER); // if there are both values use the latest one if (gpsLocation != null && networkLocation != null) { if (gpsLocation.getTime() > networkLocation.getTime()) locationResult.gotLocation(gpsLocation); else locationResult.gotLocation(networkLocation); return; } if (gpsLocation != null) { locationResult.gotLocation(gpsLocation); return; } if (networkLocation != null) { locationResult.gotLocation(networkLocation); return; } locationResult.gotLocation(null); } }; private final LocationListener locationListenerGps = new LocationListener() { public void onLocationChanged(Location location) { timer.cancel(); locationResult.gotLocation(location); locationManager.removeUpdates(this); locationManager.removeUpdates(locationListenerNetwork); } public void onProviderDisabled(String provider) { } public void onProviderEnabled(String provider) { } public void onStatusChanged(String provider, int status, Bundle extras) { } }; private final LocationListener locationListenerNetwork = new LocationListener() { public void onLocationChanged(Location location) { timer.cancel(); locationResult.gotLocation(location); locationManager.removeUpdates(this); locationManager.removeUpdates(locationListenerGps); } public void onProviderDisabled(String provider) { } public void onProviderEnabled(String provider) { } public void onStatusChanged(String provider, int status, Bundle extras) { } }; public void prepare() { locationTimeoutHandler = new Handler(locationTimeoutCallback); } public synchronized boolean getLocation(Context context, LocationResult result, int maxMillisToWait) { locationResult = result; if (locationManager == null) locationManager = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE); // exceptions will be thrown if provider is not permitted. try { gpsEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER); } catch (Exception ex) { } try { networkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER); } catch (Exception ex) { } // don't start listeners if no provider is enabled if (!gpsEnabled && !networkEnabled) return false; if (gpsEnabled) locationManager.requestSingleUpdate(LocationManager.GPS_PROVIDER, locationListenerGps, Looper.myLooper()); //locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps); if (networkEnabled) locationManager.requestSingleUpdate(LocationManager.NETWORK_PROVIDER, locationListenerNetwork, Looper.myLooper()); //locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListenerNetwork); timer = new Timer(); timer.schedule(new GetLastLocationTask(), maxMillisToWait); return true; } private class GetLastLocationTask extends TimerTask { @Override public void run() { locationTimeoutHandler.sendEmptyMessage(0); } } public static abstract class LocationResult { public abstract void gotLocation(Location location); } } I use this class from a customized looper thread, like the following one:
public class LocationGetter { private final Context context; private Location location = null; private final Object gotLocationLock = new Object(); private final LocationResult locationResult = new LocationResult() { @Override public void gotLocation(Location location) { synchronized (gotLocationLock) { LocationGetter.this.location = location; gotLocationLock.notifyAll(); Looper.myLooper().quit(); } } }; public LocationGetter(Context context) { if (context == null) throw new IllegalArgumentException("context == null"); this.context = context; } public synchronized Coordinates getLocation(int maxWaitingTime, int updateTimeout) { try { final int updateTimeoutPar = updateTimeout; synchronized (gotLocationLock) { new Thread() { public void run() { Looper.prepare(); LocationResolver locationResolver = new LocationResolver(); locationResolver.prepare(); locationResolver.getLocation(context, locationResult, updateTimeoutPar); Looper.loop(); } }.start(); gotLocationLock.wait(maxWaitingTime); } } catch (InterruptedException e1) { e1.printStackTrace(); } if (location != null) coordinates = new Coordinates(location.getLatitude(), location.getLongitude()); else coordinates = Coordinates.UNDEFINED; return coordinates; } } where Coordinates is a simple class with two properties: latitude and longitude.
Answer by krisDrOid for What is the simplest and most robust way to get the user's current location in Android?
Use the below code, it will give the best provider available:
String locCtx = Context.LOCATION_SERVICE; LocationManager locationMgr = (LocationManager) ctx.getSystemService(locCtx); Criteria criteria = new Criteria(); criteria.setAccuracy(Criteria.ACCURACY_FINE); criteria.setAltitudeRequired(false); criteria.setBearingRequired(false); criteria.setCostAllowed(true); criteria.setPowerRequirement(Criteria.POWER_LOW); String provider = locationMgr.getBestProvider(criteria, true); System.out.println("Best Available provider::::"+provider); Answer by RDC for What is the simplest and most robust way to get the user's current location in Android?
I have created small application with step by step description to gets current locations GPS co-ordinates.
Complete example source code in below URL:
See How it works :
All we need to do is add this permission in manifest file
and create LocationManager instance like this
LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);Check GPS is enabled or not
then implement LocationListener and Get Coordinates
LocationListener locationListener = new MyLocationListener(); locationManager.requestLocationUpdates( LocationManager.GPS_PROVIDER, 5000, 10, locationListener);here is the sample code to do
/*----------Listener class to get coordinates ------------- */ private class MyLocationListener implements LocationListener { @Override public void onLocationChanged(Location loc) { editLocation.setText(""); pb.setVisibility(View.INVISIBLE); Toast.makeText( getBaseContext(), "Location changed: Lat: " + loc.getLatitude() + " Lng: " + loc.getLongitude(), Toast.LENGTH_SHORT).show(); String longitude = "Longitude: " + loc.getLongitude(); Log.v(TAG, longitude); String latitude = "Latitude: " + loc.getLatitude(); Log.v(TAG, latitude); /*-------to get City-Name from coordinates -------- */ String cityName = null; Geocoder gcd = new Geocoder(getBaseContext(), Locale.getDefault()); List addresses; try { addresses = gcd.getFromLocation(loc.getLatitude(), loc.getLongitude(), 1); if (addresses.size() > 0) System.out.println(addresses.get(0).getLocality()); cityName = addresses.get(0).getLocality(); } catch (IOException e) { e.printStackTrace(); } String s = longitude + "\n" + latitude + "\n\nMy Current City is: " + cityName; editLocation.setText(s); } @Override public void onProviderDisabled(String provider) {} @Override public void onProviderEnabled(String provider) {} @Override public void onStatusChanged(String provider, int status, Bundle extras) {} } Answer by Brajendra Pandey for What is the simplest and most robust way to get the user's current location in Android?
This is the code that provides user current location
create Maps Activty:
public class Maps extends MapActivity { public static final String TAG = "MapActivity"; private MapView mapView; private LocationManager locationManager; Geocoder geocoder; Location location; LocationListener locationListener; CountDownTimer locationtimer; MapController mapController; MapOverlay mapOverlay = new MapOverlay(); @Override protected void onCreate(Bundle icicle) { super.onCreate(icicle); setContentView(R.layout.main); initComponents(); mapView.setBuiltInZoomControls(true); mapView.setSatellite(true); mapView.setTraffic(true); mapView.setStreetView(true); mapController = mapView.getController(); mapController.setZoom(16); locationManager = (LocationManager) getSystemService(LOCATION_SERVICE); if (locationManager == null) { Toast.makeText(Maps.this, "Location Manager Not Available", Toast.LENGTH_SHORT).show(); return; } location = locationManager .getLastKnownLocation(LocationManager.GPS_PROVIDER); if (location == null) location = locationManager .getLastKnownLocation(LocationManager.NETWORK_PROVIDER); if (location != null) { double lat = location.getLatitude(); double lng = location.getLongitude(); Toast.makeText(Maps.this, "Location Are" + lat + ":" + lng, Toast.LENGTH_SHORT).show(); GeoPoint point = new GeoPoint((int) (lat * 1E6), (int) (lng * 1E6)); mapController.animateTo(point, new Message()); mapOverlay.setPointToDraw(point); List listOfOverlays = mapView.getOverlays(); listOfOverlays.clear(); listOfOverlays.add(mapOverlay); } locationListener = new LocationListener() { public void onStatusChanged(String arg0, int arg1, Bundle arg2) {} public void onProviderEnabled(String arg0) {} public void onProviderDisabled(String arg0) {} public void onLocationChanged(Location l) { location = l; locationManager.removeUpdates(this); if (l.getLatitude() == 0 || l.getLongitude() == 0) { } else { double lat = l.getLatitude(); double lng = l.getLongitude(); Toast.makeText(Maps.this, "Location Are" + lat + ":" + lng, Toast.LENGTH_SHORT).show(); } } }; if (locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) locationManager.requestLocationUpdates( LocationManager.GPS_PROVIDER, 1000, 10f, locationListener); locationManager.requestLocationUpdates( LocationManager.NETWORK_PROVIDER, 1000, 10f, locationListener); locationtimer = new CountDownTimer(30000, 5000) { @Override public void onTick(long millisUntilFinished) { if (location != null) locationtimer.cancel(); } @Override public void onFinish() { if (location == null) { } } }; locationtimer.start(); } public MapView getMapView() { return this.mapView; } private void initComponents() { mapView = (MapView) findViewById(R.id.map_container); ImageView ivhome = (ImageView) this.findViewById(R.id.imageView_home); ivhome.setOnClickListener(new OnClickListener() { public void onClick(View arg0) { // TODO Auto-generated method stub Intent intent = new Intent(Maps.this, GridViewContainer.class); startActivity(intent); finish(); } }); } @Override protected boolean isRouteDisplayed() { return false; } class MapOverlay extends Overlay { private GeoPoint pointToDraw; public void setPointToDraw(GeoPoint point) { pointToDraw = point; } public GeoPoint getPointToDraw() { return pointToDraw; } @Override public boolean draw(Canvas canvas, MapView mapView, boolean shadow, long when) { super.draw(canvas, mapView, shadow); Point screenPts = new Point(); mapView.getProjection().toPixels(pointToDraw, screenPts); Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.select_map); canvas.drawBitmap(bmp, screenPts.x, screenPts.y - 24, null); return true; } } } main.xml:
and define following permission in manifest:
Answer by Mayank Saini for What is the simplest and most robust way to get the user's current location in Android?
public static Location getBestLocation(Context ctxt) { Location gpslocation = getLocationByProvider( LocationManager.GPS_PROVIDER, ctxt); Location networkLocation = getLocationByProvider( LocationManager.NETWORK_PROVIDER, ctxt); Location fetchedlocation = null; // if we have only one location available, the choice is easy if (gpslocation != null) { Log.i("New Location Receiver", "GPS Location available."); fetchedlocation = gpslocation; } else { Log.i("New Location Receiver", "No GPS Location available. Fetching Network location lat=" + networkLocation.getLatitude() + " lon =" + networkLocation.getLongitude()); fetchedlocation = networkLocation; } return fetchedlocation; } /** * get the last known location from a specific provider (network/gps) */ private static Location getLocationByProvider(String provider, Context ctxt) { Location location = null; // if (!isProviderSupported(provider)) { // return null; // } LocationManager locationManager = (LocationManager) ctxt .getSystemService(Context.LOCATION_SERVICE); try { if (locationManager.isProviderEnabled(provider)) { location = locationManager.getLastKnownLocation(provider); } } catch (IllegalArgumentException e) { Log.i("New Location Receiver", "Cannot access Provider " + provider); } return location; } Answer by Ankit Sharma for What is the simplest and most robust way to get the user's current location in Android?
Simple and best way for GeoLocation.
LocationManager lm = null; boolean network_enabled; if (lm == null) lm = (LocationManager) Kikit.this.getSystemService(Context.LOCATION_SERVICE); network_enabled = lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER); dialog = ProgressDialog.show(Kikit.this, "", "Fetching location...", true); final Handler handler = new Handler(); timer = new Timer(); TimerTask doAsynchronousTask = new TimerTask() { @Override public void run() { handler.post(new Runnable() { @Override public void run() { Log.e("counter value","value "+counter); if(counter<=8) { try { counter++; if (network_enabled) { lm = (LocationManager) Kikit.this.getSystemService(Context.LOCATION_SERVICE); Log.e("in network_enabled..","in network_enabled"); // Define a listener that responds to location updates LocationListener locationListener = new LocationListener() { public void onLocationChanged(Location location) { if(attempt == false) { attempt = true; Log.e("in location listener..","in location listener.."); longi = location.getLongitude(); lati = location.getLatitude(); Data.longi = "" + longi; Data.lati = "" + lati; Log.e("longitude : ",""+longi); Log.e("latitude : ",""+lati); if(faceboo_name.equals("")) { if(dialog!=null){ dialog.cancel();} timer.cancel(); timer.purge(); Data.homepage_resume = true; lm = null; Intent intent = new Intent(); intent.setClass(Kikit.this,MainActivity.class); startActivity(intent); finish(); } else { isInternetPresent = cd.isConnectingToInternet(); if (isInternetPresent) { if(dialog!=null) dialog.cancel(); Showdata(); } else { error_view.setText(Data.internet_error_msg); error_view.setVisibility(0); error_gone(); } } } } public void onStatusChanged(String provider, int status, Bundle extras) { } public void onProviderEnabled(String provider) { //Toast.makeText(getApplicationContext(), "Location enabled", Toast.LENGTH_LONG).show(); } public void onProviderDisabled(String provider) { } }; // Register the listener with the Location Manager to receive // location updates lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 100000, 10,locationListener); } else{ //Toast.makeText(getApplicationContext(), "No Internet Connection.", 2000).show(); buildAlertMessageNoGps(); } } catch (Exception e) { // TODO // Auto-generated // catch // block } } else { timer.purge(); timer.cancel(); if(attempt == false) { attempt = true; String locationProvider = LocationManager.NETWORK_PROVIDER; // Or use LocationManager.GPS_PROVIDER try { Location lastKnownLocation = lm.getLastKnownLocation(locationProvider); longi = lastKnownLocation.getLongitude(); lati = lastKnownLocation.getLatitude(); Data.longi = "" + longi; Data.lati = "" + lati; } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); Log.i("exception in loc fetch", e.toString()); } Log.e("longitude of last known location : ",""+longi); Log.e("latitude of last known location : ",""+lati); if(Data.fb_access_token == "") { if(dialog!=null){ dialog.cancel();} timer.cancel(); timer.purge(); Data.homepage_resume = true; Intent intent = new Intent(); intent.setClass(Kikit.this,MainActivity.class); startActivity(intent); finish(); } else { isInternetPresent = cd.isConnectingToInternet(); if (isInternetPresent) { if(dialog!=null){ dialog.cancel();} Showdata(); } else { error_view.setText(Data.internet_error_msg); error_view.setVisibility(0); error_gone(); } } } } } }); } }; timer.schedule(doAsynchronousTask, 0, 2000); private void buildAlertMessageNoGps() { final AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setMessage("Your WiFi & mobile network location is disabled , do you want to enable it?") .setCancelable(false) .setPositiveButton("Yes", new DialogInterface.OnClickListener() { public void onClick(@SuppressWarnings("unused") final DialogInterface dialog, @SuppressWarnings("unused") final int id) { startActivity(new Intent(android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS)); setting_page = true; } }) .setNegativeButton("No", new DialogInterface.OnClickListener() { public void onClick(final DialogInterface dialog, @SuppressWarnings("unused") final int id) { dialog.cancel(); finish(); } }); final AlertDialog alert = builder.create(); alert.show(); } Answer by Matt W for What is the simplest and most robust way to get the user's current location in Android?
The recommended way to do this is to use LocationClient:
First, define location update interval values. Adjust this to your needs.
private static final int MILLISECONDS_PER_SECOND = 1000; private static final long UPDATE_INTERVAL = MILLISECONDS_PER_SECOND * UPDATE_INTERVAL_IN_SECONDS; private static final int FASTEST_INTERVAL_IN_SECONDS = 1; private static final long FASTEST_INTERVAL = MILLISECONDS_PER_SECOND * FASTEST_INTERVAL_IN_SECONDS; Have your Activity implement GooglePlayServicesClient.ConnectionCallbacks, GooglePlayServicesClient.OnConnectionFailedListener, and LocationListener.
public class LocationActivity extends Activity implements GooglePlayServicesClient.ConnectionCallbacks, GooglePlayServicesClient.OnConnectionFailedListener, LocationListener {} Then, set up a LocationClientin the onCreate() method of your Activity:
public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); mLocationClient = new LocationClient(this, this, this); mLocationRequest = LocationRequest.create(); mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY); mLocationRequest.setInterval(UPDATE_INTERVAL); mLocationRequest.setFastestInterval(FASTEST_INTERVAL); } Add the required methods to your Activity; onConnected() is the method that is called when the LocationClientconnects. onLocationChanged() is where you'll retrieve the most up-to-date location.
@Override public void onConnectionFailed(ConnectionResult connectionResult) { Log.w(TAG, "Location client connection failed"); } @Override public void onConnected(Bundle dataBundle) { Log.d(TAG, "Location client connected"); mLocationClient.requestLocationUpdates(mLocationRequest, this); } @Override public void onDisconnected() { Log.d(TAG, "Location client disconnected"); } @Override public void onLocationChanged(Location location) { if (location != null) { Log.d(TAG, "Updated Location: " + Double.toString(location.getLatitude()) + "," + Double.toString(location.getLongitude())); } else { Log.d(TAG, "Updated location NULL"); } } Be sure to connect/disconnect the LocationClient so it's only using extra battery when absolutely necessary and so the GPS doesn't run indefinitely. The LocationClient must be connected in order to get data from it.
public void onResume() { super.onResume(); mLocationClient.connect(); } public void onStop() { if (mLocationClient.isConnected()) { mLocationClient.removeLocationUpdates(this); } mLocationClient.disconnect(); super.onStop(); } Get the user's location. First try using the LocationClient; if that fails, fall back to the LocationManager.
public Location getLocation() { if (mLocationClient != null && mLocationClient.isConnected()) { return mLocationClient.getLastLocation(); } else { LocationManager locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE); if (locationManager != null) { Location lastKnownLocationGPS = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER); if (lastKnownLocationGPS != null) { return lastKnownLocationGPS; } else { return locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER); } } else { return null; } } } Answer by Sheraz Ahmad Khilji for What is the simplest and most robust way to get the user's current location in Android?
Even though the answer is already given here. I just wanted to share this to the world incase the come across such scenario.
My requirement was that i needed to get a user's current location within 30 to 35 seconds at max so here is the solution i made following Nirav Ranpara's Answer.
1. I made MyLocationManager.java class which handles all the GPS and Network stuff
import java.util.concurrent.Executors; import java.util.concurrent.ScheduledExecutorService; import java.util.concurrent.TimeUnit; import com.app.callbacks.OnLocationDetectectionListener; import android.app.AlertDialog; import android.content.Context; import android.content.DialogInterface; import android.content.Intent; import android.location.Location; import android.location.LocationListener; import android.location.LocationManager; import android.os.Bundle; import android.provider.Settings; import android.util.Log; import android.widget.Toast; public class MyLocationManager { /** The minimum distance to GPS change Updates in meters **/ private final long MIN_DISTANCE_CHANGE_FOR_UPDATES_FOR_GPS = 2; // 2 // meters /** The minimum time between GPS updates in milliseconds **/ private final long MIN_TIME_BW_UPDATES_OF_GPS = 1000 * 5 * 1; // 5 // seconds /** The minimum distance to NETWORK change Updates in meters **/ private final long MIN_DISTANCE_CHANGE_FOR_UPDATES_FOR_NETWORK = 5; // 5 // meters /** The minimum time between NETWORK updates in milliseconds **/ private final long MIN_TIME_BW_UPDATES_OF_NETWORK = 1000 * 10 * 1; // 10 // seconds /** * Lets just say i don't trust the first location that the is found. This is * to avoid that **/ private int NetworkLocationCount = 0, GPSLocationCount = 0; private boolean isGPSEnabled; private boolean isNetworkEnabled; /** * Don't do anything if location is being updated by Network or by GPS */ private boolean isLocationManagerBusy; private LocationManager locationManager; private Location currentLocation; private Context mContext; private OnLocationDetectectionListener mListener; public MyLocationManager(Context mContext, OnLocationDetectectionListener mListener) { this.mContext = mContext; this.mListener = mListener; } /** * Start the location manager to find my location */ public void startLocating() { try { locationManager = (LocationManager) mContext .getSystemService(Context.LOCATION_SERVICE); // Getting GPS status isGPSEnabled = locationManager .isProviderEnabled(LocationManager.GPS_PROVIDER); // Getting network status isNetworkEnabled = locationManager .isProviderEnabled(LocationManager.NETWORK_PROVIDER); if (!isGPSEnabled && !isNetworkEnabled) { // No network provider is enabled showSettingsAlertDialog(); } else { // If GPS enabled, get latitude/longitude using GPS Services if (isGPSEnabled) { locationManager.requestLocationUpdates( LocationManager.GPS_PROVIDER, MIN_TIME_BW_UPDATES_OF_GPS, MIN_DISTANCE_CHANGE_FOR_UPDATES_FOR_GPS, gpsLocationListener); } if (isNetworkEnabled) { locationManager.requestLocationUpdates( LocationManager.NETWORK_PROVIDER, MIN_TIME_BW_UPDATES_OF_NETWORK, MIN_DISTANCE_CHANGE_FOR_UPDATES_FOR_NETWORK, networkLocationListener); } } /** * My 30 seconds plan to get myself a location */ ScheduledExecutorService se = Executors .newSingleThreadScheduledExecutor(); se.schedule(new Runnable() { @Override public void run() { if (currentLocation == null) { if (isGPSEnabled) { currentLocation = locationManager .getLastKnownLocation(LocationManager.GPS_PROVIDER); } else if (isNetworkEnabled) { currentLocation = locationManager .getLastKnownLocation(LocationManager.NETWORK_PROVIDER); } if (currentLocation != null && mListener != null) { locationManager.removeUpdates(gpsLocationListener); locationManager .removeUpdates(networkLocationListener); mListener.onLocationDetected(currentLocation); } } } }, 30, TimeUnit.SECONDS); } catch (Exception e) { Log.e("Error Fetching Location", e.getMessage()); Toast.makeText(mContext, "Error Fetching Location" + e.getMessage(), Toast.LENGTH_SHORT).show(); } } /** * Handle GPS location listener callbacks */ private LocationListener gpsLocationListener = new LocationListener() { @Override public void onStatusChanged(String provider, int status, Bundle extras) { // TODO Auto-generated method stub } @Override public void onProviderEnabled(String provider) { // TODO Auto-generated method stub } @Override public void onProviderDisabled(String provider) { // TODO Auto-generated method stub } @Override public void onLocationChanged(Location location) { if (GPSLocationCount != 0 && !isLocationManagerBusy) { Log.d("GPS Enabled", "GPS Enabled"); isLocationManagerBusy = true; currentLocation = location; locationManager.removeUpdates(gpsLocationListener); locationManager.removeUpdates(networkLocationListener); isLocationManagerBusy = false; if (currentLocation != null && mListener != null) { mListener.onLocationDetected(currentLocation); } } GPSLocationCount++; } }; /** * Handle Network location listener callbacks */ private LocationListener networkLocationListener = new LocationListener() { @Override public void onStatusChanged(String provider, int status, Bundle extras) { // TODO Auto-generated method stub } @Override public void onProviderEnabled(String provider) { // TODO Auto-generated method stub } @Override public void onProviderDisabled(String provider) { // TODO Auto-generated method stub } @Override public void onLocationChanged(Location location) { if (NetworkLocationCount != 0 && !isLocationManagerBusy) { Log.d("Network", "Network"); isLocationManagerBusy = true; currentLocation = location; locationManager.removeUpdates(gpsLocationListener); locationManager.removeUpdates(networkLocationListener); isLocationManagerBusy = false; if (currentLocation != null && mListener != null) { mListener.onLocationDetected(currentLocation); } } NetworkLocationCount++; } }; /** * Function to show settings alert dialog. On pressing the Settings button * it will launch Settings Options. * */ public void showSettingsAlertDialog() { AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext); // Setting Dialog Title alertDialog.setTitle("GPS is settings"); // Setting Dialog Message alertDialog .setMessage("GPS is not enabled. Do you want to go to settings menu?"); // On pressing the Settings button. alertDialog.setPositiveButton("Settings", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { Intent intent = new Intent( Settings.ACTION_LOCATION_SOURCE_SETTINGS); mContext.startActivity(intent); } }); // On pressing the cancel button alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { dialog.cancel(); } }); // Showing Alert Message alertDialog.show(); } } 2. I made an Interface (callback) OnLocationDetectectionListener.java in order to communicate the results back to the calling fragment or activity
import android.location.Location; public interface OnLocationDetectectionListener { public void onLocationDetected(Location mLocation); } 3. Then i made an MainAppActivty.java Activity that implements OnLocationDetectectionListener interface and here is how i receive my location in it
public class MainAppActivty extends Activity implements OnLocationDetectectionListener { private Location currentLocation; private MyLocationManager mLocationManager; @Override protected void onCreate(Bundle savedInstanceState) { setContentView(R.layout.activity_home); super.onCreate(savedInstanceState); mLocationManager = new MyLocationManager(this, this); mLocationManager.startLocating(); } @Override public void onLocationDetected(Location mLocation) { //Your new Location is received here currentLocation = mLocation; } 4. Add the following permissions to your manifest file
Hope this is helpful to others :)
Answer by Diego Palomar for What is the simplest and most robust way to get the user's current location in Android?
EDIT: Updated with the latest Location Service API from Google Play Services library (July 2014)
I would recommend you to use the new Location Service API, available from the Google Play Services library, which provides a more powerful, high-level framework that automates tasks such as location provider choice and power management. According to the official documentation: "... Location API make it easy for you to build location-aware applications, without needing to focus on the details of the underlying location technology. They also let you minimize power consumption by using all of the capabilities of the device hardware."
For further information visit: Making Your App Location-Aware
To see a full example using the latest Location Service API visit: Android LocationClient class is deprecated but used in documentation
Answer by Sandeep for What is the simplest and most robust way to get the user's current location in Android?
A bit late here but what I would in such a situation is to use Google Maps API and mark the nearby locations using lat and long API of google maps. Plus user experience is better if you can show his/her location on a map. No need to bother about the updation of user location or frisking with android api. Let google maps handle the internals for you.
@emmby may have got it resolved in his app but for future reference a look at Google maps API for location specific stuff is what I recommend to fellow developers.
Edit: Link for displaying user location in google maps
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