Develop Reference

how to get the position of user by GPS and if not availabe by Network

I am new in android developing, and so intrested in getting location of users!!!!!
You may know that we can access users location by two types:
GPS (ACCESS_FINE_LOCATON)
Network based (ACCESS_COARSE_LOCATION)
My Question is:
I Want to get the location(latittude & longitude) of user by GPS. But, if the user has turned GPS Off/GPS isn't supported, then i want to get user's location by Network, or, Network-based location
.
Hope you understood my question....
Any help is accepted

Try the following code:
LocationManager mlocManager;
mlocManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
mlocListener = new MyLocationListener();
//if condition to check if GPS is available
if (mlocManager .isProviderEnabled(LocationManager.GPS_PROVIDER)) { mlocManager.requestSingleUpdate(LocationManager.GPS_PROVIDER,
mlocListener, null);
}
else if (mlocManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)) {
mlocManager.requestSingleUpdate(
LocationManager.NETWORK_PROVIDER, mlocListener, null);
}
//this is the class to get the location.
public class MyLocationListener implements LocationListener {
#Override
public void onLocationChanged(Location location) {
// TODO Auto-generated method stub
try {
//you may store these values where ever required.
Double latitude = location.getLatitude();
Double longitude = location.getLongitude();
} catch (Exception e) {
e.printStackTrace();
}
}
#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
}
}

When you use the FusedLocationProviderApi as used in the getting the last known location training and receiving location updates training, it will automatically fall back to network location if GPS is not available.

Hope get GPS code helps you.
if (Common.getIsGPSEnabled()) {
final LocationManager locationManager = (LocationManager) c.getSystemService(Context.LOCATION_SERVICE);
LocationListener locationListener;
locationListener = new LocationListener() {
public void onLocationChanged(Location location) {
myLocation = locationManager.getLastKnownLocation(locationProvider);
Toast.makeText(c, "location changed, My location is removed to"
+ myLocation.getLatitude()+","+myLocation.getLongitude(), Toast.LENGTH_LONG).show();
Latitude = myLocation.getLatitude();
Longitude = myLocation.getLongitude();
}
public void onStatusChanged(String provider, int status, Bundle extras) {}
public void onProviderEnabled(String provider) {}
public void onProviderDisabled(String provider) {}
};
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
locationManager.requestLocationUpdates(locationProvider, (long)0, (float)0, locationListener);
myLocation = locationManager.getLastKnownLocation(locationProvider);
if(myLocation != null)
{
///
}
}

How to get the new latitude and longitude cordinates from android

How i am getting location details:
AppLocationService appLocationService = new AppLocationService(getApplicationContext());
Location nwLocation= appLocationService.getLocation(LocationManager.NETWORK_PROVIDER);
nwLocation.getLatitude();
nwLocation.getLongitude();
What is happening since my code has llast known location .... its giving me the last location that was updated say now its evening. its giving me the location updated during morning
What i want:: how can i make a fresh network request to get the current location at my position
AppLocationService.java
public class AppLocationService extends Service implements LocationListener {
protected LocationManager locationManager;
Location location;
private static final long MIN_DISTANCE_FOR_UPDATE = 0;
private static final long MIN_TIME_FOR_UPDATE = 0;
public AppLocationService(Context context) {
locationManager = (LocationManager) context.getSystemService(LOCATION_SERVICE);
}
public Location getLocation(String provider) {
if (locationManager.isProviderEnabled(provider)) {
locationManager.requestLocationUpdates(provider,
MIN_TIME_FOR_UPDATE, MIN_DISTANCE_FOR_UPDATE, this);
if (locationManager != null) {
location = locationManager.getLastKnownLocation(provider);
return location;
}
}
return null;
}
#Override
public void onLocationChanged(Location location) {
}
#Override
public void onProviderDisabled(String provider) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public IBinder onBind(Intent arg0) {
return null;
}
}

Your code is registering to receive location updates and also returns the last known location. What happens is expected because you didn't wait to receive an updated one.
Once the method "onLocationChanged" was called by the system you'll have the new one. You can then send a broadcast from the service.
You are trying to get the current location in a synchronous mode which is not possible as it takes some time to lookup the updated one.

The primary reason why you aren't getting updated location information quickly is that you're relying on the NETWORK_PROVIDER.
You should instead use this
Location location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);

How to call Explicitly onLocationChanged
public void locationlist()
{
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates( LocationManager.NETWORK_PROVIDER,
50, 0, this);
Criteria criteria = new Criteria();
provider = locationManager.getBestProvider(criteria, false);
Location location = locationManager.getLastKnownLocation(provider);
if (location != null) {
System.out.println("Provider " + provider + " has been selected.");
onLocationChanged(location);
} else {}
if(location == null)
{
}
else{
lat = (double) (location.getLatitude());
lng = (double) (location.getLongitude());
}
}
now call the method locationlist where you want like in a timer.

Use onLocationChanged method and get the longitude and latitude from the parametr location
Code:
#Override
public void onLocationChanged(Location location) {
mCurrentLocation = new Location(location);
latitude=mCurrentLocation .getLatitude();
longitude=mCurrentLocation .getLongitude();
}

android get location in background and update listview

I'm trying to program an application which is using the current location from the user and calculating the distance and writes it into my listview.
The location doesn't have to be very accurate and i only want to fetch a new location when the list is refreshed or on app start, not continously.
My problem is that the locationlistener with gps takes too long to find a location and i have to update my list a lot before it is showing the right distance.
I was thinking about implementing a background task which gets the location and updates the list automatically when it found the position. Would that be a solution?
Is there any option to get a location faster, even if it is not as accurate as gps?
what i have so far on my location listener:
public class MyLocationListener implements LocationListener {
#Override
public void onLocationChanged(Location location) {
lat = location.getLatitude();
lng = location.getLongitude();
myLoc.setLatitude(lat);
myLoc.setLongitude(lng);
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onProviderDisabled(String provider) {
}
}
in this method i'm calling the locationmanager and listener and creating the listview with the distance
public void getList(){
locationManager = (LocationManager) getActivity().getSystemService(getActivity().LOCATION_SERVICE);
locationManager.requestLocationUpdates( LocationManager.GPS_PROVIDER, 0, 0, mLocationListener);
//... creating the list with distance and so on
}
i hope you can give me some hints how i can implement this that i will work as described above or tell me what i should use instead.
thanks :)

1). You can use LocationManager.NETWORK_PROVIDER
This provider determines location based on availability of cell tower and WiFi access points. Results are retrieved by means of a network lookup. Requires either of the permissions android.permission.ACCESS_COARSE_LOCATION or android.permission.ACCESS_FINE_LOCATION.
eg:- locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 500, 50, locationListener);
2). If you want to use background task then use this service
public class LocationFinder extends Service {
public static double lat, lng;
LocationManager locationManager;
public void onDestroy() {
super.onDestroy();
if (locationManager != null && locationListener != null) {
locationManager.removeUpdates(locationListener);
}
}
#Override
public void onCreate() {
Log.v("location", "===>location ed onCreate " + lat);
super.onCreate();
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
super.onStartCommand(intent, flags, startId);
Log.v("location", "===>location ed onStartCommand " + lat + "==>" + lng);
new Handler().post(new Runnable() {
#Override
public void run() {
// TODO Auto-generated method stub
getLocation();
}
});
return START_STICKY;
}
final LocationListener locationListener = new LocationListener() {
public void onLocationChanged(Location location) {
updateWithNewLocation(location);
}
public void onProviderDisabled(String provider) {
updateWithNewLocation(null);
}
public void onProviderEnabled(String provider) {
}
public void onStatusChanged(String provider, int status, Bundle extras) {
}
};
private void getLocation() {
String context = Context.LOCATION_SERVICE;
locationManager = (LocationManager) getSystemService(context);
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_COARSE);
criteria.setAltitudeRequired(false);
criteria.setBearingRequired(false);
criteria.setCostAllowed(true);
criteria.setPowerRequirement(Criteria.POWER_LOW);
if (locationManager != null) {
String provider = locationManager.getBestProvider(criteria, true);
if (provider != null) {
Location location = locationManager.getLastKnownLocation(provider);
updateWithNewLocation(location);
locationManager.requestLocationUpdates(provider, 500, 50, locationListener);
} else {
if (locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)) {
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 500, 50, locationListener);
} else if (locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 500, 50, locationListener);
} else if (locationManager.isProviderEnabled(LocationManager.PASSIVE_PROVIDER)) {
locationManager.requestLocationUpdates(LocationManager.PASSIVE_PROVIDER, 500, 50, locationListener);
}
}
}
}
private void updateWithNewLocation(Location location) {
if (location != null) {
Log.v("location", "===>location ed " + lat);
lat = location.getLatitude();
lng = location.getLongitude();
}
}
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
}

Running GPS Values

I'm trying to get GPS values every few seconds and I'm missing some trick. Here's what I've tried:
public class Locn extends ActionBarActivity
{
private LocationManager locationManager;
private String provider;
private Location loc = null;
private Criteria criteria;
... local variables ...
#Override
protected void onCreate(Bundle savedInstanceState)
{
...
// Get the location manager
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
LocationManager service = (LocationManager) getSystemService(LOCATION_SERVICE);
boolean enabled = service.isProviderEnabled(LocationManager.GPS_PROVIDER);
// Check if enabled. If not send user to the GPS settings
if (!enabled)
{
Toast.makeText(this, "Please enable GPS location service",
Toast.LENGTH_SHORT).show();
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(intent);
}
else
{
Toast.makeText(this, "GPS location service is enabled",
Toast.LENGTH_SHORT).show();
}
// Define the criteria to select the location provider -> use default
criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
criteria.setPowerRequirement(Criteria.NO_REQUIREMENT);
// Let Android select the best location provider based on criteria
provider = locationManager.getBestProvider(criteria, true);
...
}
//--------------------------------------
// Set up timer handlers
Handler timerHandler = new Handler();
Runnable timerRunnable = new Runnable()
{
#Override
public void run()
{
provider = locationManager.getBestProvider(criteria, true);
loc = locationManager.getLastKnownLocation(provider);
milli = System.currentTimeMillis();
longitude = loc.getLongitude();
latitude = loc.getLatitude();
count++;
timerHandler.postDelayed(this, 2000);
}
};
count and milli changes every two seconds but the latitude and longitude do not change at all. (Yes, I'm changing position -- up to 2 miles)
What am I missing here? Does loc have to be cleared before calling getLastKnownLocation again?
Thanks,
Walt

Timer tm =new Timer();
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates( LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
boolean enabled = service.isProviderEnabled(LocationManager.GPS_PROVIDER);
tm.schedule(new task(),10,10000);//this execute task every 10 seconds
//use the timer task in your main activity
class task extends TimerTask {
public void run() {
Home.this.runOnUiThread(new Runnable() {
public void run() {
longitude = loc.getLongitude();
latitude = loc.getLatitude();
});
}
};

You don't need a Timer. Just use LocationManager.requestLocationUpdates()
From Android documentation:
requestLocationUpdates(String provider, long minTime, float minDistance, LocationListener listener)
See at: Android LocationManager
Just use like below:
public class MainActivity extends Activity implements LocationListener {
private String provider;
private LocationManager lm;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
provider = lm.getBestProvider(criteria, false);
Location location = lm.getLastKnownLocation(provider);
if (location != null) {
onLocationChanged(location);
}
}
#Override
protected void onResume() {
super.onResume();
lm.requestLocationUpdates(provider, 1000, 10, this);
}
#Override
protected void onPause() {
super.onPause();
lm.removeUpdates(this);
}
#Override
protected boolean isRouteDisplayed() {
return false;
}
public void onLocationChanged(Location location) {
double lat = location.getLatitude();
double lng = location.getLongitude();
}
public void onProviderDisabled(String provider) {
}
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
}

Sometimes I am getting empty location until I restart my phone why?

So I am getting the longitude and latitude as:
locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
// Define a listener that responds to location updates
locationListener = new LocationListener() {
public void onLocationChanged(Location location) {
// Called when a new location is found by the network location provider.
longitude=location.getLongitude();
latitude=location.getLatitude();
}
public void onStatusChanged(String provider, int status, Bundle extras) {}
public void onProviderEnabled(String provider) {}
public void onProviderDisabled(String provider) {}
};
//Or use LocationManager.GPS_PROVIDER
String locationProvider = LocationManager.NETWORK_PROVIDER;
// Register the listener with the Location Manager to receive location updates
locationManager.requestLocationUpdates(locationProvider, 0, 0, locationListener);
Location lastKnownLocation = locationManager.getLastKnownLocation(locationProvider);
if(lastKnownLocation!=null){
longitude=lastKnownLocation.getLongitude();
latitude=lastKnownLocation.getLatitude();
}
then I am getting my location depending on these info:
Geocoder myLocation = new Geocoder(Time.this, Locale.getDefault());
List<Address> myList=null;
try {
myList = myLocation.getFromLocation(latitude,longitude, 1);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
if(myList != null && myList.size()>0) {
address= (Address) myList.get(0);
if(address.getAddressLine(0)!=null){
addressStr += address.getAddressLine(0);
}
if(address.getAddressLine(1)!=null){
addressStr += ", "+address.getAddressLine(1);
}
if(address.getAddressLine(2)!=null){
addressStr += ", " +address.getAddressLine(2);
}
}
But sometimes the location stays null until I restart my phone why that's happening? and is there a way to fix it?

Try to setup your Location Listener as below :
public class BasicMapActivity_new2 extends Activity implements
LocationListener {
private LocationManager locationManager;
private String provider;
Double Latitude, longitude;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.basic_demo);
LocationManager service = (LocationManager) getSystemService(LOCATION_SERVICE);
boolean enabledGPS = service
.isProviderEnabled(LocationManager.GPS_PROVIDER);
boolean enabledWiFi = service
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!enabledGPS) {
Toast.makeText(BasicMapActivity_new2.this, "GPS signal not found",
Toast.LENGTH_LONG).show();
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(intent);
} else if (!enabledWiFi) {
Toast.makeText(BasicMapActivity_new2.this,
"Network signal not found", Toast.LENGTH_LONG).show();
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(intent);
}
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
// Define the criteria how to select the locatioin provider -> use
// default
Criteria criteria = new Criteria();
provider = locationManager.getBestProvider(criteria, false);
Location location = locationManager.getLastKnownLocation(provider);
if (location != null) {
onLocationChanged(location);
} else {
// do something
}
}
#Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
#Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(provider, 400, 1, this);
}
Location old_one;
#Override
public void onLocationChanged(Location location) {
double lat = location.getLatitude();
double lng = location.getLongitude();
// Toast.makeText(BasicMapActivity_new.this, "Location " + lat+","+lng,
// Toast.LENGTH_LONG).show();
LatLng coordinate = new LatLng(lat, lng);
Latitude = lat;
longitude = lng;
Toast.makeText(BasicMapActivity_new2.this,
"Location " + coordinate.latitude + "," + coordinate.longitude,
Toast.LENGTH_LONG).show();
}
#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
}
}
And do not forget to add permission into manifest.xml
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
Update: This is because to add requestLocationUpdates() into onResume() and removeUpdates(this); into onPause(). This way your app will stop updated locations when it is not active. add below into your Activity:
#Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
#Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(provider, 400, 1, this);
}

this is a documented issue in google forums. Check this thread:
https://code.google.com/p/android/issues/detail?id=57707
Also i think the solution for this is to use Google Location API, this requires that you have Google Play services up to date and >= 2.2 i think. Hope this helps you. I battled this issue for long