Android My Location-Fix - android

When my map activity is called I make a call in the onCreate to addUserMapPoint. This function contains two instances where I try to get the location information using myOverlay.getMyLocation. On the initial load of this activity the result of the first attempt returns a null GeoPoint and after the main UI thread completes the second attempt located in the listener thread of myOverlay.runOnFirstFix(new Runnable()… is call after a second and does contain a GeoPoint that does contain a lat and lon. The call inside this listener function does appear to put the dot on the map and the line mapController.animateTo(gp) does move the map to my location. My app has a refresh button that when clicked fires off this activity again. I need the lat and lon in order to fetch location data from another service. After the refresh, the second time through the map activity code I was expecting the first call to myOverlay.getMyLocation() would now be able to get the GeoPoint, but it is still null.
If I’m not able to get the GeoPoint by this first call to myOverlay.getMyLocation then how can I pass the lat and lon value from the second call found in the myOverlay.runOnFirstFix(new Runnable()… thread. You will notice that I have been trying to add the lat and lon to MyApp which is helper bean class but the lat and lon in this class is null even after the refresh. If I manually set a lat and lon manually in the addUserMapPoint function the first time the activity is accessed these values are retained. I’m guessing that this is because it is being set on the main UI thread.
public class MapActivity extends com.google.android.maps.MapActivity {
private MapView mapView = null;
private MapController mapController = null;
private MyLocationOverlay myOverlay = null;
public static MyApp app;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_map);
app = (MyApp) getApplicationContext();
mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);
mapController = mapView.getController();
List<Overlay> mapOverlays = mapView.getOverlays();
mapOverlays.clear();
addUserMapPoint(mapView);
if (!app.isLocServOff()) {
//map other points – service call to get items from our service near lat and lon
addOtherMapPoints(mapOverlays);
} else {
Toast.makeText(app.getApplicationContext(),"Current location could not be found.",Toast.LENGTH_LONG).show();
}
}
private void addUserMapPoint(MapView mapView){
myOverlay = new MyLocationOverlay(app.getApplicationContext(), mapView);
myOverlay.disableCompass();
myOverlay.enableMyLocation();
if(app.getMyLat()==null||app.getMyLon()==null){
GeoPoint gp = myOverlay.getMyLocation();
if(gp!=null){
app.setMyLat(Helper.latLon1E6Calc(gp.getLatitudeE6()));
app.setMyLon(Helper.latLon1E6Calc(gp.getLongitudeE6()));
app.setLocServOff(false);
}else{
app.setLocServOff(true);
}
}
myOverlay.runOnFirstFix(new Runnable() {
public void run() {
GeoPoint gp = myOverlay.getMyLocation();
if(gp!=null){
app.setMyLat(Helper.latLon1E6Calc(gp.getLatitudeE6()));
app.setMyLon(Helper.latLon1E6Calc(gp.getLongitudeE6()));
app.setLocServOff(false);
mapController.animateTo(gp);
}else{
app.setLocServOff(true);
}
}
});
mapView.getOverlays().add(myOverlay);
}
}
Your help is being requested for the following question.
How can I get a GeoPoint that contains a lat and lon in the main UI thread or how can I pass these values from GeoPoint I am able to get from the myOverlay.runOnFirstFix(new Runnable()… thread?
If you are going to suggest that I use Handler or runOnUiThread please provide code example that passes the lat and lon back to something that can be used by the main UI thread/map view. I have tried things like the following code that did not produce the desired outcome. I was able to get the toast message to show up, but was not able to get the lat and lon passed in a way I could use.
final Handler handler = new Handler();
myOverlay.runOnFirstFix(new Runnable() {
#Override public void run() {
handler.post(new Runnable() {
#Override public void run() {
GeoPoint gp = myOverlay.getMyLocation();
if(gp!=null){
app.setMyLat(Helper.latLon1E6Calc(gp.getLatitudeE6()));
app.setMyLon(Helper.latLon1E6Calc(gp.getLongitudeE6()));
app.setLocServOff(false);
mapController.animateTo(gp);
}else{
app.setLocServOff(true);
}
//Toast.makeText(getApplicationContext(),"wowoowowowoowoowowow",Toast.LENGTH_LONG).show();
}
});
}
});
I've also used code like the following to get the lat and lon and it works, but because the current location would sometimes be a different lat and lon than whas was being returned becuase for example I could not get a gps signal but yet an old value was returned. I added checks to see if the lat/lon data was older than 2 minutes, but I still could not match up the most recent lat and lon with that that is returned by myOverlay.getMyLocation.
LocationManager locMgr = (LocationManager)appcontext.getSystemService(Context.LOCATION_SERVICE);
MyLocationListener locLstnr = new MyLocationListener();
//fetch current location for current location
locMgr.requestSingleUpdate(LocationManager.GPS_PROVIDER, locLstnr, appcontext.getMainLooper());

Bellow you can find some examples on how to get the current location in the UI thread, but first of all, some background information.
GPS may take some time (15 seconds to 1 minute) to get the first fix after the request for new location is made. This is the reason you your first attempt to get it from myOverlay fails, and only after the first fix you can get the value.
During this blackout period you can use getLastKnownLocation() to get the last good known GPS location if you are in a hurry. If not availble it returns null
The code:
Last Known Location
LocationManager locMgr=(LocationManager)context.getSystemService(Context.LOCATION_SERVICE);
Location loc = locMgr.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if(loc != null){
//we have a valid location. Check location date
}
Requesting a Single Location Update
LocationManager locMgr=(LocationManager)context.getSystemService(Context.LOCATION_SERVICE);
locMgr.requestSingleUpdate(LocationManager.GPS_PROVIDER, locationListener, appcontext.getMainLooper);
Requesting a Continuous Location Update
LocationManager locMgr = (LocationManager)context.getSystemService(Context.LOCATION_SERVICE);
//use 0 for minDistance and minDistance between updates if you need the maximum update frequency.
locMgr.requestLocationUpdates(LocationManager.GPS_PROVIDER, minDistance, minTime, locationListener);
Location Listener for Single and Continuous position update
This is the last piece of code, and is the place where you get the new fresh locations requested above.
When a new location that match your request critirea defined above is retrieved by GPS, this listener is immediately called, unless you device is busy doing something else that can't be interrupted (i.e. callback is on a paused thread or that hit a lock).
From within the onLocationChanged() you can set any class level filed as appropriate. If you registered the listener from the UI thread, then this will be running running on the UI.
LocationListener locationListener = new LocationListener() {
public void onLocationChanged(Location fix) {
fix.setTime(fix.getTime() + timeZoneOffset); //Add Timezone offset if needed
//here you have a fresh new location in fix...
//You can set the value of any class level field from here
}
public void onProviderDisabled(String provider) {
}
public void onProviderEnabled(String provider) {
}
public void onStatusChanged(String provider, int status, Bundle extras) {
}
};
Regards.

handler.post(new Runnable() {
#Override public void run() {
GeoPoint gp = myOverlay.getMyLocation();
if(gp!=null){
app.setMyLat(Helper.latLon1E6Calc(gp.getLatitudeE6()));
app.setMyLon(Helper.latLon1E6Calc(gp.getLongitudeE6()));
app.setLocServOff(false);
// HERE WE HAVE VALID gp VALUE AND WE NEED TO SHARE IT
mapController.animateTo(gp);
}else{
app.setLocServOff(true);
}
}
});
I think that your app.set/get|MyLat/Lon not working because you call them from different threads. To fix it synchronize set and get methods for MyLat/Long. (create Object for synchronization and sync on it)
Or if you like your way with handler this should work:
final Handler handler = new Handler(); // BE SURE TO RUN THIS LINE ON UI THREAD
...
myOverlay.runOnFirstFix(new Runnable() {
#Override public void run() {
// THIS PART WORKS AS BEFORE
final GeoPoint gp = myOverlay.getMyLocation();
mapController.animateTo(gp);
...
// AND THIS RUNNABLE TO UPDATE MyLat/MyLong FROM UI THREAD
handler.post(new Runnable() {
#Override public void run() {
app.setMyLat(Helper.latLon1E6Calc(gp.getLatitudeE6()));
app.setMyLon(Helper.latLon1E6Calc(gp.getLongitudeE6()));
});
}
});

Some of the most important points you must take into account while seeking Device's location are:
Satellite GPS fix is not guaranteed to be received in adequate amount of time. E.g. the device is inside a building / not under open sky.
Make sure the satellite GPS listeners are not kept active for long. Keeping the listener ON will imply keeping the GPS radio on all the time making it the biggest battery drain reason.
In the below code example, the poll method in LinkedBlockingQueue doesn't return until either a specified time interval is over or a Location is queued in.
Use something like the below to get the current Location:
Location getCurrentLocation() {
long startmillis = 0;
LinkedBlockingQueue<Location> mQueue = new LinkedBlockingQueue<Location>();
try{
long millisSinceLastCollection = System.currentTimeMillis() - startmillis;
startmillis = System.currentTimeMillis();
mQueue.clear();
// Register for Satellite GPS listener as well as Network GPS listener.
registerGPSListeners();
// Wait for a maximum of one minutes for a fix
Location firstfix = mQueue.poll(1, TimeUnit.MINUTES);
if(firstfix != null && firstfix.getProvider().equals(LocationManager.GPS_PROVIDER)) {
return firstfix;
}
long elapsedmillis = System.currentTimeMillis() - startmillis;
long remainingmillis = ONE_MINUTE_IN_MS - elapsedmillis;
if (remainingmillis <= 0){
return firstfix;
}
Location secondfix = mQueue.poll(remainingmillis, TimeUnit.MILLISECONDS);
if(secondfix != null && secondfix.getProvider().equals(LocationManager.GPS_PROVIDER)) {
return secondfix;
}
/*
* In case we receive fix only from Network provider, return it.
*/
if(firstfix != null && firstfix.getProvider().equals(LocationManager.NETWORK_PROVIDER)) {
return firstfix;
}
} catch(Exception e){
Logger.e("GPS: Exception while listening for the current location", e);
} finally {
Logger.i("GPS: Unsubscribing from any existing GPS listeners");
unregisterGPSListeners();
}
}
// GPS issue fix edit.
private void registerGPSListeners() {
LocationManager locationManager = (LocationManager)AirWatchApp.getAppContext().getSystemService(Context.LOCATION_SERVICE);
if(locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER))
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 30000, 100, oneShotNetworkGPSLocationListener, MyAppApp.getAppContext().getMainLooper());
if(locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)){
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 30000, 100, oneShotSatelliteGPSLocationListener, AirWatchApp.getAppContext().getMainLooper());
}
}
private void unregisterGPSListeners(){
final LocationManager locationManager = (LocationManager)MyApp.getAppContext().getSystemService(Context.LOCATION_SERVICE);
locationManager.removeUpdates(oneShotSatelliteGPSLocationListener);
locationManager.removeUpdates(oneShotNetworkGPSLocationListener);
}
//One shot location listener
protected LocationListener oneShotSatelliteGPSLocationListener = new LocationListener() {
public void onLocationChanged(Location location) {
try {
mQueue.put(location);
} catch (InterruptedException e) {
Logger.e("Exception in putting new Location to the queue", e);
}
Logger.d("GPS: Location received from Satellite GPS Provider");
unregisterGPSListeners();
}
public void onProviderDisabled(String provider) {}
public void onStatusChanged(String provider, int status, Bundle extras) {}
public void onProviderEnabled(String provider) {}
};
//One shot location listener
protected LocationListener oneShotNetworkGPSLocationListener = new LocationListener() {
public void onLocationChanged(Location location) {
try {
mQueue.put(location);
} catch (InterruptedException e) {
Logger.e("Exception in putting new Location to the queue", e);
}
Logger.d("GPS: Location received from Network GPS Provider");
// Stop Listener for one-shot location fix from Network GPS provider.
final LocationManager locationManager = (LocationManager)AirWatchApp.getAppContext().getSystemService(Context.LOCATION_SERVICE);
locationManager.removeUpdates(oneShotNetworkGPSLocationListener);
Logger.d("GPS: Unsubscribed the network location listener.");
}
public void onProviderDisabled(String provider) {}
public void onStatusChanged(String provider, int status, Bundle extras) {}
public void onProviderEnabled(String provider) {}
};

Android modifies the user interface and handles input events from one single user interface thread(main thread).
If the programmer does not use any concurrency constructs, all code of an Android application runs in this thread.
GPS is the best way to determine a user's location, but pinging a global positioning satellite too much will quickly drain a mobile device's battery, take long time to get user location and this method doesn't always work indoors. You are not getting your location in first attempt that's why you are getting null over there.
Android's Network Location Provider figures out a user's location based on cell tower and Wi-Fi signals. It not only uses less battery power than GPS, but it's also faster and it works whether the user is outside or inside.
I am giving my Working Code below that show progress dialog, listen for user's location & after getting location show user's location overlay on Google-map
I assume that you have give below permissions in your Menifest file
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.INTERNET"/>
My main class
public class MyLocationOnMap extends MapActivity {
private MapView mapView;
private MyLocationOverlay itemizedoverlay;
private LocationManager locationManager;
private String provider;
private MyLocationListener locationListener;
MyBroadCastreceiver myBroadCastreceiver;
/**
* My current Location <i>longitude</i>.
*/
static int longitude;
/**
* My current Location <i>latitude</i>.
*/
static int latitude;
/**
*My progress indicator.
*/
ProgressDialog loadingDialog;
public static final String INTENT_FILTER_TAG="my location broadcast receiver";
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.my_location_on_map);
loadingDialog = new ProgressDialog(this);
loadingDialog.setTitle("Hot Spots!");
loadingDialog.setMessage("Please wait ...");
loadingDialog.setIndeterminate(true);
loadingDialog.setCancelable(false);
loadingDialog.show();
// Configure the Map
mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);
mapView.setStreetView(true);
/**
* Get your location manager and Location Listener...
*/
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationListener=new MyLocationListener();
myBroadCastreceiver = new MyBroadCastreceiver();
if (locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
Log.i("GPS_Enabled", "GPS enable! listening for gps location.");
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 10000, 0, locationListener);
registerReceiver(myBroadCastreceiver, new IntentFilter(INTENT_FILTER_TAG));
} else if (locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)) {
Log.i("Network_Enabled", "Network enable! listening for Network location.");
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 10000, 0, locationListener);
registerReceiver(myBroadCastreceiver, new IntentFilter(INTENT_FILTER_TAG));
} else {
loadingDialog.dismiss();
Toast.makeText(this, "No Provider enable!", Toast.LENGTH_LONG).show();
}
}//End of onCreate......
/**
* My BroadCast Receiver, that is called when i get the location of user.
* #author Rupesh Yadav.
*
*/
class MyBroadCastreceiver extends BroadcastReceiver{
#Override
public void onReceive(Context context, Intent intent) {
//Remove location update when you get user`s location very first time.
locationManager.removeUpdates(locationListener);
//Remove the broadcast listener that update my location on map.
unregisterReceiver(myBroadCastreceiver);
GeoPoint point = new GeoPoint(latitude, longitude);
mapView.getController().animateTo(point);
List<Overlay> mapOverlays = mapView.getOverlays();
Drawable drawable = MyLocationOnMap.this.getResources().getDrawable(R.drawable.hs_mapoverlay);
itemizedoverlay = new MyLocationOverlay(drawable, MyLocationOnMap.this);
OverlayItem overlayitem = new OverlayItem(point, "Hello!", "My Current Location :)");
itemizedoverlay.addOverlay(overlayitem);
mapOverlays.add(itemizedoverlay);
loadingDialog.dismiss();
}
}
/**
* My Location listener...
*/
class MyLocationListener implements LocationListener{
#Override
public void onLocationChanged(Location location) {
latitude=(int) ((location.getLatitude())*1E6);
longitude=(int) ((location.getLongitude())*1E6);
//Send broadcast to update my location.
Intent sendLocationIntent=new Intent(INTENT_FILTER_TAG);
sendBroadcast(sendLocationIntent);
}
#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
}
}
#Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
}
MyLocationOverlay class
public class MyLocationOverlay extends ItemizedOverlay<OverlayItem> {
Context mContext;
private ArrayList<OverlayItem> hsOverlays = new ArrayList<OverlayItem>();
public MyLocationOverlay(Drawable defaultMarker) {
super(boundCenterBottom(defaultMarker));
// TODO Auto-generated constructor stub
}
public MyLocationOverlay(Drawable defaultMarker, Context context) {
super(boundCenterBottom(defaultMarker));
mContext = context;
}
#Override
protected OverlayItem createItem(int i) {
// TODO Auto-generated method stub
return hsOverlays.get(i);
}
#Override
public int size() {
// TODO Auto-generated method stub
return hsOverlays.size();
}
/**
* add new OverlayItem objects to map OverlayItem ArrayList.
*
* #param overlay
*/
public void addOverlay(OverlayItem overlay) {
hsOverlays.add(overlay);
populate();
}
/**
* Called when user clicks on map overlay.
*/
#Override
protected boolean onTap(int index) {
// TODO Auto-generated method stub
// return super.onTap(index);
OverlayItem item = hsOverlays.get(index);
AlertDialog.Builder dialog = new AlertDialog.Builder(mContext);
dialog.setTitle(item.getTitle());
dialog.setMessage(item.getSnippet());
dialog.show();
return true;
}
You can modify the Location Listener & Broadcasr Receiver according to your need.
I hope this will solve your problem.
Best regards!

I have used this class for detecting my lat & lon:
Hope this is useful for you too.
Example how to use:
GPSUtility.getInstance(Context).getLatitude();
GPSUtility.getInstance(CamPhotoModeAct.this).getLongitude()
public class GPSUtility {
public static final String TAG = "GPSUtility";
private Context ctx;
Timer timer1;
LocationManager lm;
LocationResult locationResult;
boolean gps_enabled=false;
boolean network_enabled=false;
private double latitude;
private double longitude;
private static SharedPreferences SHARED_PREF;
private static SharedPreferences.Editor EDITOR_SHARED_PREF;
private static GPSUtility this_instance;
public GPSUtility(Context ctx){
this.ctx = ctx;
SHARED_PREF = ctx.getSharedPreferences(ConstantsG.SHARED_PREF_FILE, Context.MODE_PRIVATE);
EDITOR_SHARED_PREF = SHARED_PREF.edit();
this.getLocation(innerLocationResult);
}
public static GPSUtility getInstance(Context ctx){
if(this_instance == null)
this_instance = new GPSUtility(ctx);
return this_instance;
}
public static void updateLocation(Context ctx){
GPSUtility.getInstance(ctx);//this writes the latitude and longitude in sharable preference file
}
public double getLatitude(){
String latitudeStr = SHARED_PREF.getString(ConstantsG.KEY_LATITUDE,null);
if(latitudeStr == null){
latitude = 0.0;
}
else{
latitude = Double.parseDouble(latitudeStr);
}
return latitude;
}
public double getLongitude(){
String longitudeStr = SHARED_PREF.getString(ConstantsG.KEY_LONGITUDE,null);
if(longitudeStr == null){
longitude = 0.0;
}
else{
longitude = Double.parseDouble(longitudeStr);
}
return longitude;
}
private void updateWithNewLocation(Location location) {
if (location != null) {
latitude = location.getLatitude();
EDITOR_SHARED_PREF.putString(ConstantsG.KEY_LATITUDE, String.valueOf(latitude) );
longitude = location.getLongitude();
EDITOR_SHARED_PREF.putString(ConstantsG.KEY_LONGITUDE, String.valueOf(longitude));
EDITOR_SHARED_PREF.commit();
}
}
public boolean getLocation(LocationResult result)
{
//I use LocationResult callback class to pass location value from GPSUtility to user code.
locationResult=result;
if(lm==null)
lm = (LocationManager) this.ctx.getSystemService(Context.LOCATION_SERVICE);
//exceptions will be thrown if provider is not permitted.
try {
gps_enabled = lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
} catch (Exception ex) {
Log.e(TAG, "Exception error: " + ex.getLocalizedMessage(), ex);
}
try {
network_enabled = lm
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
} catch (Exception ex) {
Log.e(TAG, "Exception error: " + ex.getLocalizedMessage(), ex);
}
//Toast.makeText(context, gps_enabled+" "+network_enabled, Toast.LENGTH_LONG).show();
//don't start listeners if no provider is enabled
if(!gps_enabled && !network_enabled){
Toast.makeText(this.ctx, "You should enable gps or be connected to network.", Toast.LENGTH_LONG).show();
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(), 10000);
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() {
//Context context = getClass().getgetApplicationContext();
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);
}
LocationResult innerLocationResult = new LocationResult() {
#Override
public void gotLocation(Location location) {
updateWithNewLocation(location);
}
};
}

Related

Android - Can't refresh user location on activity launch

I'm stuck trying to refresh the user's location.
In my app, I start the map marking user's current location, but locationManager.getLastKnownLocation() is returning a different location
because it uses a cache location.
How can I compare the last known location with the current location so I can mark the correct position on the map in the callback OnMapReady?
Every example I found in StackOverflow is using LocationListener.onLocationChanged() method, but I need to refresh the location (if needed) on activity launch.
Code:
private static final String TAG_MAP_LOAD_FAILED = "FAIL LOADING MAP STYLE";
private static final String TAG_MAP_PARSING_FAILED = "FAIL PARSING MAP STYLE";
private GoogleMap mMap;
private LatLng mMyCoordinates;
private LocationManager mLocationManager;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mLocationManager = (LocationManager) getContext().getSystemService(Context.LOCATION_SERVICE);
getMapAsync(this);
}
#Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
try{
boolean success = googleMap.setMapStyle(MapStyleOptions.loadRawResourceStyle(getContext(), R.raw.style_mapjson));
if(!success){
Log.e(TAG_MAP_PARSING_FAILED, "Failed parsing JSON Style");
}
}catch (Resources.NotFoundException ex){
Log.e(TAG_MAP_LOAD_FAILED, "Can't find style. Error:", ex);
}
mMap.setIndoorEnabled(false);
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(mMyCoordinates);
markerOptions.title("Marker in my location");
mMap.addMarker(markerOptions);
CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(mMyCoordinates, 15);
mMap.moveCamera(cameraUpdate);
mMap.getUiSettings().setRotateGesturesEnabled(false);
}
#Override
public void onLocationChanged(Location location) {
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onProviderDisabled(String provider) {
}
OBS: I cleaned up the code because it was getting full of unsuccessful attempts. Just showing how it is structured.
Should I use FusedLocation instead?
The last known location has a timestamp associated with it, which can be quite some time in the past. Just do an age comparison with the last known location's timestamp with the max age you'd allow, and request an update when needed. Here is a quick and dirty example:
private static long MAX_TIME = 60 * 60 * 1000; //Update if location is older than one hour
#Override
public void onResume() {
super.onResume();
Location location = mLocationManager.getLastKnownLocation(YOUR_PROVIDER_HERE); //GPS or Network
boolean shouldUpdateLocation = false;
if (location != null) {
long elapsedTime = System.currentTimeMillis() - location.getTime();
if (elapsedTime >= MAX_TIME) {
shouldUpdateLocation = true;
}
}
else {
shouldUpdateLocation = true;
}
if (shouldUpdateLocation) {
//TODO: Request location update here.
}
}
You don't want to be requesting location updates every time the activity is brought up, so set up a reasonable MAX_TIME for this.

I always get the values of latitude=0 and longitude=0 in android when I try to get current user's location. How to fix it?

Class that implements LocationListener and get last know location using GPS in android API level 23. This class include the functions of getting the current user's latitude and longitude.
public class Teacher_Location extends Service implements LocationListener {
private final Context mContext;
// flag for GPS status
boolean isGPSEnabled = false;
// flag for network status
boolean isNetworkEnabled = false;
// flag for GPS status
boolean canGetLocation = false;
Location location; // location
double latitude; // latitude
double longitude; // longitude
// The minimum distance to change Updates in meters
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 0; // 10 meters
// The minimum time between updates in milliseconds
private static final long MIN_TIME_BW_UPDATES =0; // 1 minute
// Declaring a Location Manager
protected LocationManager locationManager;
public Teacher_Location(Context context) {
this.mContext = context;
getLocation();
}
public Location getLocation() {
try {
locationManager = (LocationManager) mContext
.getSystemService(LOCATION_SERVICE);
// getting GPS status
isGPSEnabled = locationManager
.isProviderEnabled(LocationManager.GPS_PROVIDER);
// getting network status
if (!isGPSEnabled) {
// no network provider is enabled
} else {
this.canGetLocation = true;
// if GPS Enabled get lat/long using GPS Services
if (isGPSEnabled) {
if (location == null) {
if(locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)){
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
}
Log.d("GPS Enabled", "GPS Enabled");
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
return location;
}
/**
* Stop using GPS listener
* Calling this function will stop using GPS in your app
* */
public void stopUsingGPS(){
if(locationManager != null){
locationManager.removeUpdates(Teacher_Location.this);
}
}
/**
* Function to get latitude
* */
public double getLatitude(){
if(location != null){
latitude = location.getLatitude();
}
// return latitude
return latitude;
}
/**
* Function to get longitude
* */
public double getLongitude(){
if(location != null){
longitude = location.getLongitude();
}
// return longitude
return longitude;
}
/**
* Function to check GPS/wifi enabled
* #return boolean
* */
public boolean canGetLocation() {
return this.canGetLocation;
}
/**
* Function to show settings alert dialog
* On pressing Settings button will lauch Settings Options
* */
public void showSettingsAlert(){
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 Settings button
alertDialog.setPositiveButton("Settings", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int which) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mContext.startActivity(intent);
}
});
// on pressing cancel button
alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// Showing Alert Message
alertDialog.show();
}
#Override
public void onLocationChanged(Location loc) {
this.location=loc;
}
#Override
public void onProviderDisabled(String provider) {
showSettingsAlert();
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public IBinder onBind(Intent arg0) {
return null;
}
}
here is the code for for getting latitude and longitude from the class Teacher_Location that implements LocationListener.
teacher_location=new Teacher_Location(this);
if(teacher_location.canGetLocation())
{
double latitude = teacher_location.getLatitude();
double longitude = teacher_location.getLongitude();
// \n is for new line
Toast.makeText(getApplicationContext(), "Your Location is - \nLat: " + latitude + "\nLong: " + longitude, Toast.LENGTH_LONG).show();
teacher_location.stopUsingGPS();
}
else
{
teacher_location.showSettingsAlert();
}
In my case this is showing latitude=0 and longitude=0 also.teach me
How to get current latitude and longitude in android studio.
click here to view screen shot of my activity
The location manager performs it's job asynchronously - thats why you need a listener.
You instantiate Teacher_Location class which in turn starts listening for location and immediately you request the location from it (But it hasn't found your location yet).
Basically, you are trying to read the values from the location object before it was able to get your updated location, thus returning 0 for both longitude and latitude (Default value).
Instead you need to listen for location changes in onLocationChanged (Location location) method. It will inform you on new location updates and based on that you can perform additional actions.
The key here is that it is asynchronous and you must wait for the data to be provided to you by the listener callbacks.
You can use following code sample to get started.
public class CurrentLocation {
Timer timer;
LocationManager locationManager;
LocationResult locationResult;
boolean gpsEnabled=false;
boolean networkEnabled=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(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.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps);
if(networkEnabled)
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListenerNetwork);
timer =new Timer();
timer.schedule(new GetLastLocation(), 20000);
return true;
}
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) {}
};
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) {}
};
class GetLastLocation extends TimerTask {
#Override
public void run() {
locationManager.removeUpdates(locationListenerGps);
locationManager.removeUpdates(locationListenerNetwork);
Location net_loc=null, gps_loc=null;
if(gpsEnabled)
gps_loc= locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if(networkEnabled)
net_loc= locationManager.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 void cancelTimer() {
timer.cancel();
locationManager.removeUpdates(locationListenerGps);
locationManager.removeUpdates(locationListenerNetwork);
}
public static abstract class LocationResult{
public abstract void gotLocation(Location location);
}
}
Use Google API Client to get the location.
To get the location
https://developer.android.com/training/location/retrieve-current.html
To get the location updates
https://developer.android.com/training/location/receive-location-updates.html

How can I make automatic a process?

I make a tutorial of GPS that you can get the location pressing a button, but now I want to make this process automatically, I try calling it on the onCreate method but only works once.... any Idea how? this is what i try:
GPS CLASS
public class GPS implements LocationListener{
private final Context mContext;
//flag for GPS status
boolean isGPSEnable = false;
// Flag for network status
boolean isNetworkEnable = false;
// flag for GPS status
boolean canGetLocation = false;
Location location; //location
double latitude; //latitude
double longitude; //longitude
// the minimum distances to change Updates in meters
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // Minimun distance 10 meters
// The minimum time between updates in millisenconds
private static final long MIN_TIME_BTW_UPDATES = 1000 * 60 * 1; // 1 MINUTE
// Declaring a Location Manager
protected LocationManager locationManager;
public GPS(Context context){
this.mContext = context;
getLocation();
}
public Location getLocation() {
try {
locationManager = (LocationManager) mContext
.getSystemService(Context.LOCATION_SERVICE);
//getting GPS status
isGPSEnable = locationManager
.isProviderEnabled(LocationManager.GPS_PROVIDER);
//getting network status
isNetworkEnable = locationManager
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if(!isGPSEnable && !isNetworkEnable){
// no network provider is enable
}
else {
this.canGetLocation = true;
if(isNetworkEnable){
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER,
MIN_TIME_BTW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, (LocationListener) this);
Log.d("Network", "Network");
if(locationManager != null){
location = locationManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if(location != null){
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
// if GPS Enable get lat/long using GPS Services
if(isGPSEnable){
if(location == null){
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BTW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("GPS ENABLE", "GPS Enabled");
if(locationManager != null){
location = locationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null){
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
}
}
}catch (Exception e){
e.printStackTrace();
}
return location;
}
/**
* Stop using GPS listener
* Calling this function will stop using GPS in your app
*/
public void stopUsingGPS(){
if (locationManager != null){
locationManager.removeUpdates((LocationListener) GPS.this);
}
}
/**
* function to get latitude
*/
public double getLatitude(){
if(location != null){
latitude = location.getLatitude();
}
//return latitude
return latitude;
}
public double getLongitude(){
if(location != null){
longitude = location.getLongitude();
}
//return longitude
return longitude;
}
/**
* Function to check GPS/wifi enable
* #return boolean
*/
public boolean canGetLocation(){
return this.canGetLocation;
}
/**
* Function to show settings alert dialog
* On pressing Settings button will launch Settings Options
*/
public void showSettingsAlert(){
AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
// Setting Dialog Title
alertDialog.setTitle(mContext.getString(R.string.AlertDialog_Tittle));
// Setting Dialog Message
alertDialog.setMessage(mContext.getString(R.string.dialog_message));
// On pressing Setting button
alertDialog.setPositiveButton("Settings", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
}
});
// On pressing cancel button
alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
}
#Override
public void onLocationChanged(Location location){
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onProviderDisabled(String provider) {
}
#Override
public IBinder onBind(Intent intent) {
return null;
}
}
and the main-activity class:
public class MainActivity extends ActionBarActivity {
private EditText edTLatitud;
private EditText edTLongitud;
private EditText edTCompass;
private EditText edTDirecc;
private SensorManager sensorManager;
private Sensor compassSensor;
// GPS class
GPS gps;
// Compass class
Compass compass;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.gpsactivity);
edTCompass = (EditText)this.findViewById(R.id.edTxtBrujula);
edTDirecc = (EditText)this.findViewById(R.id.edTxtBrujdireccion);
edTLatitud = (EditText)this.findViewById(R.id.edTxtLatitud);
edTLongitud = (EditText)this.findViewById(R.id.edTxtLongitud);
sensorManager = (SensorManager)getSystemService(SENSOR_SERVICE);
compassSensor = sensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);
gps = new GPS(MainActivity.this);
// Check if GPS is enable
if(gps.canGetLocation()){
double latitude = gps.getLatitude();
double longitude = gps.getLongitude();
// Print on the screen the coordinates
UpdateGPSonScreen(latitude, longitude);
}
else {
// can't get location
// GPS or network is not enable
// Ask user to enable GPS/network in settings
gps.showSettingsAlert();
}
}
// Show the Latitude and longitude of the GPS on the application
public void UpdateGPSonScreen(double latitude, double longitude)
{
try{
edTLatitud.setText(String.valueOf(latitude));
edTLongitud.setText(String.valueOf(longitude));
}
catch (Exception e)
{
e.printStackTrace();
}
}
thanks in advance...
Do you want the EditText to be updated with the user location information intermittently? If so, you could create a thread that on intervals calls a function that retrieves the location data.
If the GPS class is not used anywhere else except in MainActivity make it as inner class of your Activity or Implement LocationListener in your Activity class itself to update your TextViews inside onLocationChanged method.
Put locationManger null check before you use it anywhere, there is no sense an to check for null after using it multiple times.
Your Class structure should be like
public class MainActivity extends ActionBarActivity{
// Define your text views to use them globally
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.gpsactivity);
//find all your views
}
class GPS implements LocationListener{
//copy all your code here with required correction
#Override
public void onLocationChanged(Location location){
//get your latitude and longitude from location Object
// call same method to update your view
}
}
}
I have written whole code in stackoverflow editor only so make correction if any syntax error is found.

Android Location Services Not Updating requestLocationUpdates

I have a simple class GPSListener which gets the GPS coordinates:
public class GPSListener implements LocationListener {
public static double latitude;
public static double longitude;
#Override
public void onLocationChanged(Location loc)
{
loc.getLatitude();
loc.getLongitude();
latitude = loc.getLatitude();
longitude = loc.getLongitude();
Log.d("GPSLISTENER ", "lat: "+latitude+" long:"+longitude);
} ...
Then trying to make use of this class in my activity, I simply invoke the class in my onCreate() function in my activity:
LocationManager mlocManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
LocationListener mlocListener = new GPSListener();
Criteria criteria = new Criteria();
String bestProvider = mlocManager.getBestProvider(criteria, false);
mlocManager.requestLocationUpdates(bestProvider, 0, 0, mlocListener);
mlocManager.requestLocationUpdates( LocationManager.GPS_PROVIDER, 0, 0, mlocListener);
if (mlocManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
lat = GPSListener.latitude;
lon = GPSListener.longitude;
Log.d("GPS", "lat: "+lat+" long:"+lon);
} else {
// TODO: GPS not enabled
Log.d("GPSERROR", "GPS not enabled");
}
But whenever I run the application, lat and lon in my activity are always zero. I'm not quite sure how to get around this issue.
When logging:
Log.d("GPSLISTENER ", "lat: "+latitude+" long:"+longitude);
It returns the correct latitude and longitude, it just takes a second or two after the activity starts.
Log.d("GPSSUCCESS", "lat: "+lat+" long:"+lon);
Just returns 0.0 for both. I was under the impression that .requestLocationUpdates would pass the value to lat and lon before the if statement is executed. How can I accomplish this?
You are using public static field for latitude, longitude.
Please change it to non static and using setter, getter with instant object:
lat = mlocListener.getLatitude();
lon = mlocListener.getLongitude();
Google updated its location handling logic. It is now easier to listen location updates with fused location provider. You can implement your location listener in 5 min. Take a look.
Methods for getting the most accurate location
You are listening only gps provider and it is not ready(on waiting for location status) yet and then it does not return any location. Just take a look at fused location provider and write your location listener again.
try this...
mGoogleMap.setOnMyLocationButtonClickListener(new OnMyLocationButtonClickListener() {
#Override
public boolean onMyLocationButtonClick()
{
try
{
Location myLocation = mGoogleMap.getMyLocation();
onLocationChanged(myLocation);
}
catch (Exception e)
{
Log.getStackTraceString(e);
}
return false;
}
});
user this Handler to get Location
private Handler customHandler = new Handler();
private Runnable updateTimerThread = new Runnable() {
#Override
public void run()
{
try
{
Location myLocation = mGoogleMap.getMyLocation();
secndLocationListener.onLocationChanged(myLocation);
}
catch (Exception e)
{
Log.getStackTraceString(e);
}
}
};
to run this
customHandler.postDelayed(updateTimerThread , 1000);
LocationManager uses the last known location from the cache. The cache is updated when you load google maps. Try this out, go out in the open and check your location. Move to a different location about 200m and check your location again. It will be same as the old one. Now, load google maps, you will notice that you application magically now has the new location.
You need to programmatically kick that cache to the latest location. The only way to do that is
YOUR_APPLICATION_CONTEXT.getLocationManager().requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, 0, 0, new LocationListener() {
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onProviderDisabled(String provider) {
}
#Override
public void onLocationChanged(final Location location) {
}
});

What is the simplest and most robust way to get the user's current location on Android?

The LocationManager API on 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 Activity X, it will be available.
I 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?
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.
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 found 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);
Iterable<GpsSatellite>satellites = status.getSatellites();
sat_count = 0;
Iterator<GpsSatellite>satI = 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!
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.
I have created small application with step by step description to gets current locations GPS co-ordinates.
Complete example source code in below URL:
Get Current Location coordinates , City name - in Android
See How it works :
All we need to do is add this permission in manifest file
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION">
</uses-permission>
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<Address> 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) {}
}
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.
I have written detailed tutorial covering current location here on demonuts.com.You can find more description here and also you can download whole demo source code for better understanding.
There are already many answers there but I want to show latest way to get location using Google API, so new programmers can use new method:
First of all, put this in gradle file
compile 'com.google.android.gms:play-services:8.4.0'
then implement necessary interfaces
public class MainActivity extends BaseActivitiy implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, com.google.android.gms.location.LocationListener
declare instances
private GoogleApiClient mGoogleApiClient;
private Location mLocation;
private LocationManager locationManager;
private LocationRequest mLocationRequest;
put this in onCreate()
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
At last, override necessary methods
#Override
public void onConnected(Bundle bundle) {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, 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;
}
mLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if(mLocation == null){
startLocationUpdates();
}
if (mLocation != null) {
double latitude = mLocation.getLatitude();
double longitude = mLocation.getLongitude();
} else {
// Toast.makeText(this, "Location not Detected", Toast.LENGTH_SHORT).show();
}
}
protected void startLocationUpdates() {
// Create the location request
mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(UPDATE_INTERVAL)
.setFastestInterval(FASTEST_INTERVAL);
// Request location updates
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, 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;
}
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient,
mLocationRequest, this);
Log.d("reque", "--->>>>");
}
#Override
public void onConnectionSuspended(int i) {
Log.i(TAG, "Connection Suspended");
mGoogleApiClient.connect();
}
#Override
public void onConnectionFailed(ConnectionResult connectionResult) {
Log.i(TAG, "Connection failed. Error: " + connectionResult.getErrorCode());
}
#Override
public void onStart() {
super.onStart();
mGoogleApiClient.connect();
}
#Override
public void onStop() {
super.onStop();
if (mGoogleApiClient.isConnected()) {
mGoogleApiClient.disconnect();
}
}
#Override
public void onLocationChanged(Location location) {
}
Don't forget to start GPS in your device before running app.
Actualy we can use the two providers(GPS & NETWORK). 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.
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.
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);
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;
}
}
}
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
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
Hope this is helpful to others :)
Improvements to #Fedor's solution.
Rather than requesting location with '0' time interval and '0' distance, we can use the location manager's requestSingleUpdate method. Updated code(kotlin version)
import android.annotation.SuppressLint
import android.content.Context
import android.location.Criteria
import android.location.Location
import android.location.LocationListener
import android.location.LocationManager
import android.os.Bundle
import java.util.*
#SuppressLint("MissingPermission")
class AppLocationProvider {
private lateinit var timer: Timer
private var locationManager: LocationManager? = null
private lateinit var locationCallBack: LocationCallBack
private var gpsEnabled = false
private var networkEnabled = false
private var locationListener: LocationListener = object : LocationListener {
override fun onLocationChanged(location: Location) {
timer.cancel()
locationCallBack.locationResult(location)
}
override fun onProviderDisabled(provider: String) {}
override fun onProviderEnabled(provider: String) {}
override fun onStatusChanged(provider: String, status: Int, extras: Bundle) {}
}
fun getLocation(context : Context, callBack: LocationCallBack): Boolean {
locationCallBack = callBack
if (locationManager == null)
locationManager = context.getSystemService(Context.LOCATION_SERVICE) as LocationManager?
//exceptions will be thrown if provider is not permitted.
try {
gpsEnabled = locationManager!!.isProviderEnabled(LocationManager.GPS_PROVIDER)
} catch (ex: Exception) {
ex.printStackTrace()
}
try {
networkEnabled = locationManager!!.isProviderEnabled(LocationManager.NETWORK_PROVIDER)
} catch (ex: Exception) {
ex.printStackTrace()
}
//don't start listeners if no provider is enabled
if (!gpsEnabled && !networkEnabled)
return false
val criteria = Criteria()
if (gpsEnabled) {
criteria.accuracy = Criteria.ACCURACY_FINE
} else {
criteria.accuracy = Criteria.ACCURACY_COARSE
}
locationManager!!.requestSingleUpdate(criteria, locationListener, null)
timer = Timer()
timer.schedule(GetLastKnownLocation(), 5000)
return true
}
inner class GetLastKnownLocation : TimerTask() {
override fun run() {
locationManager!!.removeUpdates(locationListener)
var netLoc: Location? = null
var gpsLoc: Location? = null
if (gpsEnabled)
gpsLoc = locationManager!!.getLastKnownLocation(LocationManager.GPS_PROVIDER)
if (networkEnabled)
netLoc = locationManager!!.getLastKnownLocation(LocationManager.NETWORK_PROVIDER)
//check which value use the latest one
if (gpsLoc != null && netLoc != null) {
if (gpsLoc.time > netLoc.time)
locationCallBack.locationResult(gpsLoc)
else
locationCallBack.locationResult(netLoc)
return
}
if (gpsLoc != null) {
locationCallBack.locationResult(gpsLoc)
return
}
if (netLoc != null) {
locationCallBack.locationResult(netLoc)
return
}
locationCallBack.locationResult(null)
}
}
interface LocationCallBack {
fun locationResult(location: Location?)
}
}
To get location need to just call getLocation method as -
AppLocationProvider().getLocation(context, object : AppLocationProvider.LocationCallBack {
override fun locationResult(location: Location?) {
// use location, this might get called in a different thread if a location is a last known location. In that case, you can post location on main thread
}
})
Note:
Before calling getLocation method, required location permission must be granted.
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;
}
This is the way I am requesting User Permissions.
Outside your application tag in AndroidManifest.xml add these permission requests.
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
Then add Google's Location dependencies in the App Gradle file.
implementation 'com.google.android.gms:play-services-location:15.0.0'
Now declare some Global variables.
private lateinit var mFusedLocationProvider:FusedLocationProviderClient
private lateinit var mLocationCallback: LocationCallback
private lateinit var mLocationRequest: LocationRequest
private var mLocationPermissionGranted:Boolean = false
In OnCreate method of your Activity (I was not able to Format the Code Properly, Apology for that)
mFusedLocationProvider = LocationServices.getFusedLocationProviderClient(this)
//Location Callback
mLocationCallback = object: LocationCallback(){
override fun onLocationResult(p0: LocationResult?) {
if(p0==null){
//todo(request user to enable location from settings then remove return)
return
}else{
getDeviceLocation()
}
}
}
//Location Request
mLocationRequest = LocationRequest.create()
mLocationRequest.priority = LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY
//Set the Interval for Latest Interval Update
mLocationRequest.interval = 5000
//Set How Many Location Updated you Want
mLocationRequest.numUpdates = 1
getLocationPermission()
getDeviceLocation()
Now create both the functions.
private fun getLocationPermission() {
val permission:Array<String> = arrayOf(android.Manifest.permission.ACCESS_FINE_LOCATION,android.Manifest.permission.ACCESS_COARSE_LOCATION)
if(ContextCompat.checkSelfPermission(applicationContext,Constant.FINE_LOCATION)== PermissionChecker.PERMISSION_GRANTED){
if(ContextCompat.checkSelfPermission(applicationContext,Constant.COARSE_LOCATION)== PermissionChecker.PERMISSION_GRANTED){
mLocationPermissionGranted = true
}
}else{
ActivityCompat.requestPermissions(this,permission,Constant.LOCATION_REQUEST_CODE)
}
}
Second Method
private fun getDeviceLocation() {
try{
if(mLocationPermissionGranted){
mFusedLocationProvider.lastLocation.addOnCompleteListener(this,{task: Task<Location> ->
if(task.isSuccessful){
var currentLocation: Location? = task.result
if(currentLocation!=null){
Log.i("Location","Latitude is ${currentLocation.latitude} and Longitude" +
"${currentLocation.longitude}")
}
else
mFusedLocationProvider.requestLocationUpdates(mLocationRequest,mLocationCallback,null)
}
})
}
}catch (e:SecurityException){
Log.e("Error", "Security Exception ${e.message}")
}
}
For Constant.kt
class Constant{
companion object {
//Location Request Settings
const val SET_INTERVAL:Long = 2000
const val NUM_UPDATES:Int = 1
//Location Permission
const val FINE_LOCATION:String = android.Manifest.permission.ACCESS_FINE_LOCATION
const val COARSE_LOCATION:String = android.Manifest.permission.ACCESS_COARSE_LOCATION
}
}
From last more than one year, I was using the combination of GPS_PROVIDER and NETWORK_PROVIDER to get the current location and it was working good, but from last few months I'm getting location after a long delay, so I switched to latest API FusedLocationProviderClient and it is working pretty good.
Here is the class which I wrote to get current location by using FusedLocationProviderClient.
In below code, I used a timer to wait for while to get the current location, I scheduled timer 15 seconds delay, you can change it according to you.
private static FusedLocationService ourInstance;
private final LocationRequest locationRequest;
private FusedLocationProviderClient mFusedLocationClient;
private Location mLastLocation;
private Context context;
private FindOutLocation findOutLocation;
private boolean callbackTriggered = false;
private Timer timer;
public static FusedLocationService getInstance(Context pContext) {
if (null == ourInstance) ourInstance = new FusedLocationService(pContext);
return ourInstance;
}
private FusedLocationService(Context pContext) {
context = pContext;
mFusedLocationClient = LocationServices.getFusedLocationProviderClient(context);
locationRequest = getLocationRequest();
requestLocation(context);
}
public Location getLastKnownLocation() {
return mLastLocation;
}
private void requestLocation(Context context) {
if (ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
mFusedLocationClient.requestLocationUpdates(locationRequest, mLocationCallback, null);
mFusedLocationClient.getLastLocation().addOnSuccessListener(location -> {
if (location != null) {
mLastLocation = location;
triggerCallback(mLastLocation);
}
});
}
private LocationRequest getLocationRequest() {
LocationRequest locationRequest = new LocationRequest();
long INTERVAL = 10 * 1000;
long FASTEST_INTERVAL = 5 * 1000;
locationRequest.setInterval(INTERVAL);
locationRequest.setFastestInterval(FASTEST_INTERVAL);
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
return locationRequest;
}
private LocationCallback mLocationCallback = new LocationCallback() {
#Override
public void onLocationResult(LocationResult locationResult) {
for (Location location : locationResult.getLocations()) {
if (location != null) mLastLocation = location;
}
if (null != mLastLocation) triggerCallback(mLastLocation);
}
};
public static abstract class FindOutLocation {
public abstract void gotLocation(Location location);
}
#SuppressLint("MissingPermission")
public void findLocation(FindOutLocation findOutLocation) {
long TIMER_TIME_OUT = 15 * 1000;
this.findOutLocation = findOutLocation;
callbackTriggered = false;
try {
requestLocation(context);
timer = new Timer();
timer.schedule(new GetLastLocation(context), TIMER_TIME_OUT);
} catch (Exception e) {
e.printStackTrace();
}
}
private class GetLastLocation extends TimerTask {
Context context;
GetLastLocation(Context context) {
this.context = context;
}
#Override
public void run() {
triggerCallback(mLastLocation);
}
}
private void triggerCallback(Location location) {
if (null != location) mLastLocation = location;
if (!callbackTriggered && null != findOutLocation) {
callbackTriggered = true;
removeLocationUpdates();
findOutLocation.gotLocation(location);
findOutLocation = null;
}
}
private void removeLocationUpdates() {
if (null != timer) timer.cancel();
if (null != mFusedLocationClient)
mFusedLocationClient.removeLocationUpdates(mLocationCallback);
}
}
And called this from activity, here is the code
FusedLocationService.FindOutLocation findOutLocation = new FusedLocationService.FindOutLocation() {
#Override
public void gotLocation(Location currentLocation) {
if (currentLocation != null) {
/*TODO DO SOMETHING WITH CURRENT LOCATION*/
}
}
};
FusedLocationService.getInstance(this).findLocation(findOutLocation);
Add following entries in the AndroidManifest.xml
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<!-- Needed only if your app targets Android 5.0 (API level 21) or higher. -->
<uses-feature android:name="android.hardware.location.gps" />
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.
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<Overlay> 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:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:color/black"
android:orientation="vertical" >
<com.google.android.maps.MapView
android:id="#+id/map_container"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:apiKey="yor api key"
android:clickable="true"
android:focusable="true" />
</LinearLayout>
and define following permission in manifest:
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
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
It requires lots of things in place to get location updates in android,
requires lots of bolierplate code.
You need to take care of
Google Play services availablity Check,
Update Google play Service if it is old or not available
Dialog Creation of GoogleApiClient and its callbacks connected,disconnected etc.
Stopping and releasing resources for location updates
Handling Location permission scenarios
Checking Location services are On or Off
Getting lastknown location is not so easy either
Fallback to last known location if not getting location after certain duration
I have created Android-EasyLocation (small android library) which will take care all this stuff and you can focus on business logic.
All you need is extend EasyLocationActivity and this
requestSingleLocationFix(easyLocationRequest);
or
requestLocationUpdates(easyLocationRequest);
Checkout sample app and steps needed here at https://github.com/akhgupta/Android-EasyLocation
Kotlin version of #Fedor Greate answer:
usage of class:
val locationResult = object : MyLocation.LocationResult() {
override fun gotLocation(location: Location?) {
val lat = location!!.latitude
val lon = location.longitude
Toast.makeText(context, "$lat --SLocRes-- $lon", Toast.LENGTH_SHORT).show()
}
}
val myLocation = MyLocation()
myLocation.getLocation(inflater.context, locationResult)
MyLocation Class :
class MyLocation {
internal lateinit var timer1: Timer
internal var lm: LocationManager? = null
internal lateinit var locationResult: LocationResult
internal var gps_enabled = false
internal var network_enabled = false
internal var locationListenerGps: LocationListener = object : LocationListener {
override fun onLocationChanged(location: Location) {
timer1.cancel()
locationResult.gotLocation(location)
lm!!.removeUpdates(this)
lm!!.removeUpdates(locationListenerNetwork)
}
override fun onProviderDisabled(provider: String) {}
override fun onProviderEnabled(provider: String) {}
override fun onStatusChanged(provider: String, status: Int, extras: Bundle) {}
}
internal var locationListenerNetwork: LocationListener = object : LocationListener {
override fun onLocationChanged(location: Location) {
timer1.cancel()
locationResult.gotLocation(location)
lm!!.removeUpdates(this)
lm!!.removeUpdates(locationListenerGps)
}
override fun onProviderDisabled(provider: String) {}
override fun onProviderEnabled(provider: String) {}
override fun onStatusChanged(provider: String, status: Int, extras: Bundle) {}
}
fun getLocation(context: Context, result: LocationResult): Boolean {
//I use LocationResult callback class to pass location value from MyLocation to user code.
locationResult = result
if (lm == null)
lm = context.getSystemService(Context.LOCATION_SERVICE) as LocationManager?
//exceptions will be thrown if provider is not permitted.
try {
gps_enabled = lm!!.isProviderEnabled(LocationManager.GPS_PROVIDER)
} catch (ex: Exception) {
}
try {
network_enabled = lm!!.isProviderEnabled(LocationManager.NETWORK_PROVIDER)
} catch (ex: Exception) {
}
//don't start listeners if no provider is enabled
if (!gps_enabled && !network_enabled)
return false
if (ActivityCompat.checkSelfPermission(context,
Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED ||
ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) run {
ActivityCompat.requestPermissions(context as Activity,
arrayOf(Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION), 111)
}
if (gps_enabled)
lm!!.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0f, locationListenerGps)
if (network_enabled)
lm!!.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0f, locationListenerNetwork)
timer1 = Timer()
timer1.schedule(GetLastLocation(context), 20000)
return true
}
internal inner class GetLastLocation(var context: Context) : TimerTask() {
override fun run() {
lm!!.removeUpdates(locationListenerGps)
lm!!.removeUpdates(locationListenerNetwork)
var net_loc: Location? = null
var gps_loc: Location? = null
if (ActivityCompat.checkSelfPermission(context,
Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED ||
ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED
) run {
ActivityCompat.requestPermissions(context as Activity,
arrayOf(Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION),111)
}
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)
}
}
abstract class LocationResult {
abstract fun gotLocation(location: Location?)
}
}
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();
}
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
Here's what I do:
First of all I check whether NETWORK or GPS providers are enabled. Some may be disabled on the device, some may be disabled in application manifest. If any provider is enabled, I fetch cached last location for this provider and start location update listeners for this provider.
There is a method to determine whether a location is better than last received location as mentioned in link :- https://developer.android.com/guide/topics/location/strategies.html#BestEstimate
If I get update from location listener I check whether this location is better than previously received location. and If it is better than replace this location to previous best location(mFinalLocation).
There is also a handler(timer) for two minutes, which eventually stops the service and in onDestroy() method of service, stop listening for location updates for each of the provider.
Below is the code for service. You can run it based upon frequency of location update you need.
import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.support.annotation.Nullable;
import android.util.Log;
public class RecordLocationService extends Service {
private final String TAG = RecordLocationService.class.getSimpleName();
private final int TWO_MINUTES = 1000 * 60 * 2;
private LocationManager mLocationManager;
private MyLocationListener mLocationListeners[] = new MyLocationListener[]{
new MyLocationListener(LocationManager.NETWORK_PROVIDER),
new MyLocationListener(LocationManager.GPS_PROVIDER)
};
private Location mFinalLocation;
private class MyLocationListener implements LocationListener {
private String mProvider;
public MyLocationListener(String provider) {
Log.d(TAG, "LocationListener : " + provider);
mProvider = provider;
}
public String getProvider() {
return mProvider;
}
#Override
public void onLocationChanged(Location location) {
Log.d(TAG, "onLocationChanged : " + location);
if (isBetterLocation(location, mFinalLocation)) {
Log.d(TAG, "Setting current Final Location to recent most Location for Provider : " + location.getProvider());
Log.d(TAG, "Setting current Final Location to : " + location);
mFinalLocation = location;
} else {
Log.d(TAG, "Keeping current Final Location to previous Final Location");
}
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
Log.d(TAG, "onStatusChanged provider " + provider);
}
#Override
public void onProviderEnabled(String provider) {
Log.d(TAG, "onProviderEnabled provider " + provider);
}
#Override
public void onProviderDisabled(String provider) {
Log.d(TAG, "onProviderDisabled provider " + provider);
}
}
private Handler mStopServiceHandler = new Handler() {
#Override
public void handleMessage(Message msg) {
switch (msg.what) {
case 1: {
stopSelf();
}
break;
}
}
};
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
super.onStartCommand(intent, flags, startId);
Log.d(TAG, "onStartCommand");
return START_STICKY;
}
#Override
public void onCreate() {
super.onCreate();
Log.d(TAG, "onCreate");
requestLocation();
mStopServiceHandler.sendEmptyMessageDelayed(1, TWO_MINUTES);
}
private void requestLocation() {
// Acquire a reference to the system Location Manager
if (mLocationManager == null) {
mLocationManager = (LocationManager) this.getApplicationContext().getSystemService(Context.LOCATION_SERVICE);
}
try {
if (mLocationManager.getAllProviders().contains(LocationManager.NETWORK_PROVIDER) && mLocationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)) {
Log.d(TAG, "Fetching Cached Location for Provider : " + LocationManager.NETWORK_PROVIDER);
Location cachedNetworkLocation = mLocationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (cachedNetworkLocation != null) {
Log.d(TAG, "Setting Final Location to Cached Location for Provider : " + LocationManager.NETWORK_PROVIDER);
Log.d(TAG, "Setting Final Location to : " + cachedNetworkLocation);
mFinalLocation = cachedNetworkLocation;
} else {
Log.d(TAG, "Cached Location for Provider : " + LocationManager.NETWORK_PROVIDER + " is NULL");
}
Log.d(TAG, "Requesting Location Update for Provider : " + LocationManager.NETWORK_PROVIDER);
mLocationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, mLocationListeners[0]);
}
} catch (SecurityException se) {
Log.e(TAG, se.getMessage(), se);
} catch (IllegalArgumentException iae) {
Log.e(TAG, iae.getMessage(), iae);
}
try {
if (mLocationManager.getAllProviders().contains(LocationManager.GPS_PROVIDER) && mLocationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
Log.d(TAG, "Fetching Cached Location for Provider : " + LocationManager.GPS_PROVIDER);
Location cachedGPSLocation = mLocationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (cachedGPSLocation != null) {
if (isBetterLocation(cachedGPSLocation, mFinalLocation)) {
Log.d(TAG, "Setting Final Location to Cached Location for Provider : " + LocationManager.GPS_PROVIDER);
Log.d(TAG, "Setting Final Location to : " + cachedGPSLocation);
mFinalLocation = cachedGPSLocation;
}
} else {
Log.d(TAG, "Cached Location for Provider : " + LocationManager.GPS_PROVIDER + " is NULL");
}
Log.d(TAG, "Requesting Location Update for Provider : " + LocationManager.GPS_PROVIDER);
mLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, mLocationListeners[1]);
}
} catch (SecurityException se) {
Log.e(TAG, se.getMessage(), se);
} catch (IllegalArgumentException iae) {
Log.e(TAG, iae.getMessage(), iae);
}
}
/**
* Determines whether one Location reading is better than the current Location fix
*
* #param location The new Location that you want to evaluate
* #param currentBestLocation The current Location fix, to which you want to compare the new one
*/
protected boolean isBetterLocation(Location location, Location currentBestLocation) {
if (currentBestLocation == null) {
// A new location is always better than no location
return true;
}
// Check whether the new location fix is newer or older
long timeDelta = location.getTime() - currentBestLocation.getTime();
boolean isSignificantlyNewer = timeDelta > TWO_MINUTES;
boolean isSignificantlyOlder = timeDelta < -TWO_MINUTES;
boolean isNewer = timeDelta > 0;
// If it's been more than two minutes since the current location, use the new location
// because the user has likely moved
if (isSignificantlyNewer) {
return true;
// If the new location is more than two minutes older, it must be worse
} else if (isSignificantlyOlder) {
return false;
}
// Check whether the new location fix is more or less accurate
int accuracyDelta = (int) (location.getAccuracy() - currentBestLocation.getAccuracy());
boolean isLessAccurate = accuracyDelta > 0;
boolean isMoreAccurate = accuracyDelta < 0;
boolean isSignificantlyLessAccurate = accuracyDelta > 200;
// Check if the old and new location are from the same provider
boolean isFromSameProvider = isSameProvider(location.getProvider(),
currentBestLocation.getProvider());
// Determine location quality using a combination of timeliness and accuracy
if (isMoreAccurate) {
return true;
} else if (isNewer && !isLessAccurate) {
return true;
} else if (isNewer && !isSignificantlyLessAccurate && isFromSameProvider) {
return true;
}
return false;
}
/**
* Checks whether two providers are the same
*/
private boolean isSameProvider(String provider1, String provider2) {
if (provider1 == null) {
return provider2 == null;
}
return provider1.equals(provider2);
}
#Override
public void onDestroy() {
super.onDestroy();
Log.d(TAG, "onDestroy");
if (mLocationManager != null) {
for (int i = 0; i < mLocationListeners.length; i++) {
try {
Log.d(TAG, "Removing Location Update for Provider : " + mLocationListeners[i].getProvider());
mLocationManager.removeUpdates(mLocationListeners[i]);
} catch (Exception ex) {
Log.e(TAG, "fail to remove location listeners, ignore", ex);
}
}
}
}
}
In the Activity Class makes a customized method :
private void getTheUserPermission() {
ActivityCompat.requestPermissions(this, new String[]
{Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_LOCATION);
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
LocationGetter locationGetter = new LocationGetter(FreshMenuSearchActivity.this, REQUEST_LOCATION, locationManager);
if (!locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
locationGetter.OnGPS();
} else {
locationGetter.getLocation();
}
}
Make a UserDefined Class name LocationGetter:-
public class LocationGetter {
private int REQUEST_LOCATION;
private FreshMenuSearchActivity mContext;
private LocationManager locationManager;
private Geocoder geocoder;
public LocationGetter(FreshMenuSearchActivity mContext, int requestLocation, LocationManager locationManager) {
this.mContext = mContext;
this.locationManager = locationManager;
this.REQUEST_LOCATION = requestLocation;
}
public void getLocation() {
if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(mContext,
Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(mContext, new String[]
{Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_LOCATION);
} else {
Location LocationGps = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
Location LocationNetwork = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
Location LocationPassive = locationManager.getLastKnownLocation(LocationManager.PASSIVE_PROVIDER);
if (LocationGps != null) {
double lat = LocationGps.getLatitude();
double longi = LocationGps.getLongitude();
getTheAddress(lat, longi);
} else if (LocationNetwork != null) {
double lat = LocationNetwork.getLatitude();
double longi = LocationNetwork.getLongitude();
getTheAddress(lat, longi);
} else if (LocationPassive != null) {
double lat = LocationPassive.getLatitude();
double longi = LocationPassive.getLongitude();
getTheAddress(lat, longi);
} else {
Toast.makeText(mContext, "Can't Get Your Location", Toast.LENGTH_SHORT).show();
}
}
}
private void getTheAddress(double latitude, double longitude) {
List<Address> addresses;
geocoder = new Geocoder(mContext, Locale.getDefault());
try {
addresses = geocoder.getFromLocation(latitude, longitude, 1);
String address = addresses.get(0).getAddressLine(0);
String city = addresses.get(0).getLocality();
String state = addresses.get(0).getAdminArea();
String country = addresses.get(0).getCountryName();
String postalCode = addresses.get(0).getPostalCode();
String knownName = addresses.get(0).getFeatureName();
Log.d("neel", address);
} catch (IOException e) {
e.printStackTrace();
}
}
public void OnGPS() {
final AlertDialog.Builder builder = new AlertDialog.Builder(mContext);
builder.setMessage("Enable GPS").setCancelable(false).setPositiveButton("YES", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
mContext.startActivity(new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS));
}
}).setNegativeButton("NO", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
final AlertDialog alertDialog = builder.create();
alertDialog.show();
}
}
some of these ans are now out of date, so im answering,
FusedLocationProviderClient fusedLocationProviderClient; //set global variable
Location currentLocation;//set global var
private boolean mLocationPermissionGranted; //set global var
fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(getContext()); //write this oncreate
fetchLastLocation(); // call the funct for current location
//here is the function
private void fetchLastLocation() {
if (ActivityCompat.checkSelfPermission(getContext(), Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(getActivity(),new String[]{
Manifest.permission.ACCESS_FINE_LOCATION},REQUEST_CODE);
return;
}else {
mLocationPermissionGranted=true;
}
Task<Location> task= fusedLocationProviderClient.getLastLocation();
task.addOnSuccessListener(new OnSuccessListener<Location>() {
#Override
public void onSuccess(Location location) {
if(location != null){
currentLocation =location;
Toast.makeText(getContext(), currentLocation.getLatitude()+"" +
" "+currentLocation.getLongitude(),
Toast.LENGTH_SHORT).show();
//if you want to show in google maps
SupportMapFragment supportMapFragment =(SupportMapFragment)
getChildFragmentManager().findFragmentById(R.id.map);
supportMapFragment.getMapAsync(MapsFragment.this);
}
}
});
}
By using FusedLocationProviderApi which is the latest API and the best among the available possibilities to get location in Android.
add this in build.gradle file
dependencies {
compile 'com.google.android.gms:play-services:6.5.87'
}
you can get full source code by this url
http://javapapers.com/android/android-location-fused-provider/
Recently refactored to obtain the location of the code, learn some good ideas, and finally achieved a relatively perfect library and Demo.
//request all valid provider(network/gps)
private boolean requestAllProviderUpdates() {
checkRuntimeEnvironment();
checkPermission();
if (isRequesting) {
EasyLog.d("Request location update is busy");
return false;
}
long minTime = getCheckTimeInterval();
float minDistance = getCheckMinDistance();
if (mMapLocationListeners == null) {
mMapLocationListeners = new HashMap<>();
}
mValidProviders = getValidProviders();
if (mValidProviders == null || mValidProviders.isEmpty()) {
throw new IllegalArgumentException("Not available provider.");
}
for (String provider : mValidProviders) {
LocationListener locationListener = new LocationListener() {
#Override
public void onLocationChanged(Location location) {
if (location == null) {
EasyLog.e("LocationListener callback location is null.");
return;
}
printf(location);
mLastProviderTimestamp = location.getTime();
if (location.getProvider().equals(LocationManager.GPS_PROVIDER)) {
finishResult(location);
} else {
doLocationResult(location);
}
removeProvider(location.getProvider());
if (isEmptyValidProviders()) {
requestTimeoutMsgInit();
removeUpdates();
}
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onProviderDisabled(String provider) {
}
};
getLocationManager().requestLocationUpdates(provider, minTime, minDistance, locationListener);
mMapLocationListeners.put(provider, locationListener);
EasyLog.d("Location request %s provider update.", provider);
}
isRequesting = true;
return true;
}
//remove request update
public void removeUpdates() {
checkRuntimeEnvironment();
LocationManager locationManager = getLocationManager();
if (mMapLocationListeners != null) {
Set<String> keys = mMapLocationListeners.keySet();
for (String key : keys) {
LocationListener locationListener = mMapLocationListeners.get(key);
if (locationListener != null) {
locationManager.removeUpdates(locationListener);
EasyLog.d("Remove location update, provider is " + key);
}
}
mMapLocationListeners.clear();
isRequesting = false;
}
}
//Compared with the last successful position, to determine whether you need to filter
private boolean isNeedFilter(Location location) {
checkLocation(location);
if (mLastLocation != null) {
float distance = location.distanceTo(mLastLocation);
if (distance < getCheckMinDistance()) {
return true;
}
if (location.getAccuracy() >= mLastLocation.getAccuracy()
&& distance < location.getAccuracy()) {
return true;
}
if (location.getTime() <= mLastProviderTimestamp) {
return true;
}
}
return false;
}
private void doLocationResult(Location location) {
checkLocation(location);
if (isNeedFilter(location)) {
EasyLog.d("location need to filtered out, timestamp is " + location.getTime());
finishResult(mLastLocation);
} else {
finishResult(location);
}
}
//Return to the finished position
private void finishResult(Location location) {
checkLocation(location);
double latitude = location.getLatitude();
double longitude = location.getLongitude();
float accuracy = location.getAccuracy();
long time = location.getTime();
String provider = location.getProvider();
if (mLocationResultListeners != null && !mLocationResultListeners.isEmpty()) {
String format = "Location result:<%f, %f> Accuracy:%f Time:%d Provider:%s";
EasyLog.i(String.format(format, latitude, longitude, accuracy, time, provider));
mLastLocation = location;
synchronized (this) {
Iterator<LocationResultListener> iterator = mLocationResultListeners.iterator();
while (iterator.hasNext()) {
LocationResultListener listener = iterator.next();
if (listener != null) {
listener.onResult(location);
}
iterator.remove();
}
}
}
}
Complete code: https://github.com/bingerz/FastLocation/blob/master/fastlocationlib/src/main/java/cn/bingerz/fastlocation/FastLocation.java
*Each request to complete the location, it is best to removeUpdates, otherwise the phone status bar will always display the positioning icon.
After seeing all the answers, and question (Simplest and Robust). I got clicked about only library Android-ReactiveLocation.
When i made an location tracking app. Then i realized that its very typical to handle location tracking with optimised with battery.
So i want tell freshers and also developers who don't want to maintain their location code with future optimisations. Use this library.
ReactiveLocationProvider locationProvider = new
ReactiveLocationProvider(context);
locationProvider.getLastKnownLocation()
.subscribe(new Consumer<Location>() {
#Override
public void call(Location location) {
doSthImportantWithObtainedLocation(location);
}
});
Dependencies to put in app level build.gradle
dependencies {
...
compile 'pl.charmas.android:android-reactive-location2:2.1#aar'
compile 'com.google.android.gms:play-services-location:11.0.4' //you can use newer GMS version if you need
compile 'com.google.android.gms:play-services-places:11.0.4'
compile 'io.reactivex:rxjava:2.0.5' //you can override RxJava version if you need
}
Pros to use this lib:
This lib is and will be actively maintained.
You dont worry about battery optimisation. As developers have done their best.
Easy installation, put dependency and play.
easily connect to Play Services API
obtain last known location
subscribe for location updates use
location settings API
manage geofences
geocode location to list of addresses
activity recognition
use current place API fetch place
autocomplete suggestions

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