When I run my app on Android 4.2 OS phone, I can't seem to be able to get any values returned from getLAstKnownLocation ( always null )
The weird thing is that the Mapview works fine and it shows me my current location !!
Any ideas how to solve this issue ?
here is my code
in onCreate:
mlocManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
provider = mlocManager.getBestProvider(criteria, false);
mlocManager.requestLocationUpdates(provider, 0, 0, geoHandler);
then the listener:
public class GeoUpdateHandler implements LocationListener {
public void onLocationChanged(Location location) {
// called when the listener is notified with a location update from the GPS
int lat = (int) (location.getLatitude() * 1E6);
int lng = (int) (location.getLongitude() * 1E6);
new GeoPoint(lat, lng);
Log.d(this.getClass().getSimpleName(), "onLocationChanged " + lat);
// mlocManager.removeUpdates(this);
}
public void onProviderDisabled(String provider) {
// called when the GPS provider is turned off (user turning off the GPS on the phone)
Log.d(TAG, "DISABLED");
}
public void onProviderEnabled(String provider) {
// called when the GPS provider is turned on (user turning on the GPS on the phone)
Log.d(TAG, "ENABLED");
}
public void onStatusChanged(String provider, int status, Bundle extras) {
// called when the status of the GPS provider changes
Log.d(TAG, "CHANGED");
}
}
getLastKnownLocation will return a null when the provider is disabled. Or when there is no LastKnownLocation.
On the line: provider = mlocManager.getBestProvider(criteria, false);
your provider is asking for the BestProvider including disabled providers. Try using true at the end of the statement and see if that works.
http://developer.android.com/reference/android/location/LocationManager.html#getLastKnownLocation(java.lang.String)
Related
I want to get my current latitude and longitude using Mobile network provider, not GPS. AKA it should work without GPS with just your sim card. i have found many tutorials online claiming they find location with gps or network. however, they all seem to use GPS only! here or here and also here i don't want last knows location, as i don't wish to use GPS
Try This Code you can get current location without opening GPS
btnNWShowLocation.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
Location nwLocation = appLocationService
.getLocation(LocationManager.NETWORK_PROVIDER);
if (nwLocation != null) {
double latitude = nwLocation.getLatitude();
double longitude = nwLocation.getLongitude();
Toast.makeText(
getApplicationContext(),
"Mobile Location (NW): \nLatitude: " + latitude
+ "\nLongitude: " + longitude,
Toast.LENGTH_LONG).show();
} else {
showSettingsAlert("NETWORK");
}
}
});
Do it via Location Manager.
LocationManager locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
// Define a listener that responds to location updates
LocationListener locationListener = new LocationListener() {
public void onLocationChanged(Location location) {
// Called when a new location is found by the network location provider.
makeUseOfNewLocation(location);
}
public void onStatusChanged(String provider, int status, Bundle extras) {}
public void onProviderEnabled(String provider) {}
public void onProviderDisabled(String provider) {}
};
// Register the listener with the Location Manager to receive location updates
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
In an app I am working on I am getting the GPS coordinates of the device inside the activity's onCreate() method. However, even after launching the app, I see the location services icon that keeps flashing in the notifications bar of the device, it this expected or should it go away after getting the position of the device?
This is my code at the moment:
if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_DENIED)
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
1);
Criteria criteria = new Criteria();
LocationManager lm = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
lm.requestLocationUpdates(lm.getBestProvider(criteria, true), 2000, 0, new android.location.LocationListener() {
#Override
public void onLocationChanged(Location location) {
double latitude = location.getLatitude();
double longitude = location.getLongitude();
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onProviderDisabled(String provider) {
}
});
// Get latitude and longitude
Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
longitude = location.getLongitude();
latitude = location.getLatitude();
You are never telling LocationManager to stop providing location updates. To do that, call LocationManager.removeUpdates() with the correct listener as argument.
Alternatively, you can use LocationManager.requestSingleUpdate(...) which automatically stops providing updates after the first location.
I tried to get current location using GPS Providers.
But it's not working properly as far as I know. In case of Network provider it returns Tower values, not exactly the satellites values.
Here with I attached some of code samples related to GPS Provider.
LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000L, 500.0f,this);
public void onLocationChanged(Location location) {
if (location != null) {
double lat = location.getLatitude();
double lng = location.getLongitude();
String currentLocation = "Lat: " + lat + " Lng: " + lng;
txted.setText(currentLocation);
p = new GeoPoint((int) lat * 1000000, (int) lng * 1000000);
mc.animateTo(p);
}
}
public void onProviderDisabled(String provider) {
// required for interface, not used
}
public void onProviderEnabled(String provider) {
// required for interface, not used
}
public void onStatusChanged(String provider, int status, Bundle extras) {
// required for interface, not used
}
make sure that "use GPS satellites " is enabled,
go from settings -> location and security-> use GPS satellites.
Try this
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0,this);
later you get updates as per your requirement.
getLastKnownLocation always return null value. I have enabled geo fix and gps on emulator. However, there is no gps signal on the notification bar when running this on emulator. May I know is there any mistake in my code? Thanks.
public void onCreate(Bundle savedInstanceState) {
LocationManager location = null;
super.onCreate(savedInstanceState);
setContentView(R.layout.near_layout);
location = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.NO_REQUIREMENT);
criteria.setPowerRequirement(Criteria.NO_REQUIREMENT);
String bestProvider = location.getBestProvider(criteria, true);
LocationListener ll = new mylocationlistener();
Location loc = location.getLastKnownLocation(bestProvider);
if(loc != null)
{
double latitude = loc.getLatitude();
double longitude = loc.getLongitude();
Toast.makeText(nearPlace.this, " nice" + latitude, Toast.LENGTH_LONG).show();
}else{
Toast.makeText(nearPlace.this, "Location not available. GPS is not enabled.", Toast.LENGTH_LONG).show();
}
location.requestLocationUpdates(bestProvider, 0, 0, ll);
}
private class mylocationlistener implements LocationListener {
#Override
public void onLocationChanged(Location location) {
Toast.makeText(nearPlace.this, " nice" + location.getLatitude(), Toast.LENGTH_LONG).show();
nearPlaceDownloaderTask getNearPlace = new nearPlaceDownloaderTask();
getNearPlace.execute(ANDROID_WEB_LINK + "gt.php?la=" + location.getLatitude() + "&lo=" + location.getLongitude());
}
public void onProviderDisabled(String provider) {}
public void onProviderEnabled(String provider) {}
public void onStatusChanged(String provider, int status, Bundle extras) {}
}
The reason your code is not working, is because you have specified the following criteria:
criteria.setAccuracy(Criteria.NO_REQUIREMENT);
Android will prefer to use network location over GPS, because you don't care about the accuracy. By specifying an accuracy of 20 meters or so, it will probably automatically invoke GPS.
To manually invoke GPS location updates, override bestProvider:
bestProvider = LocationManager.GPS_PROVIDER;
You can really simplify this into two lines of code:
LocationManager locationManager =
(LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, interval,
precision, listener);
Don't forget to unregister your listener:
locationManager.removeUpdates(listener);
You might also want to check this out geofix not working
Also make sure you have mock locations allowed set in the emulator. Take a look at Pauls answer as well, which is why I was asking in comments what provider was returned
I created this earlier on today, but it is not working. Location manager returns null, and I've even implemented the listener. Any ideas to the problems. thanks.
Edited:
I think this line is the problem
Location location = locationManager.getLastKnownLocation(provider);
Basically, if location is null, it will go into the else part of the if statement below it. Every time I compile the code, it will go into the else statement meaning it location is not updating.
public class Activity1 extends Activity implements LocationListener {
/** Called when the activity is first created. */
JoshTwoActivity main;
Activity2 two;
boolean checkTick = false;
String locationplace = "";
private LocationManager locationManager;
private String provider;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
provider = locationManager.getBestProvider(criteria, false);
System.out.println(provider);
System.out.println(locationManager.getProviders(criteria, false));
System.out.println(locationManager.getProvider("network"));
System.out.println(locationManager.getAllProviders());
Location location = locationManager.getLastKnownLocation(provider);
System.out.println(locationManager.isProviderEnabled(provider));
// Initialize the location fields
if (location != null) {
System.out.println("Provider " + provider + " has been selected.");
int lat = (int) (location.getLatitude());
int lng = (int) (location.getLongitude());
System.out.println(String.valueOf(lat));
System.out.println(String.valueOf(lng));
} else {
System.out.println("Provider not available");
System.out.println("Provider not available");
}
}
/* Request updates at startup */
#Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(provider, 400, 1, this);
}
/* Remove the locationlistener updates when Activity is paused */
#Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
#Override
public void onLocationChanged(Location location) {
int lat = (int) (location.getLatitude());
int lng = (int) (location.getLongitude());
System.out.println(String.valueOf(lat));
System.out.println(String.valueOf(lng));
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
#Override
public void onProviderEnabled(String provider) {
Toast.makeText(this, "Enabled new provider " + provider,
Toast.LENGTH_SHORT).show();
}
#Override
public void onProviderDisabled(String provider) {
Toast.makeText(this, "Disenabled provider " + provider,
Toast.LENGTH_SHORT).show();
}
}
getLastKnownLocation() returns a location with the last known location fix for a provider. If the provider returns null, the provider has never had a location fix. It doesn't mean the provider is not available.
Once you call getLastKnownLocation() you should check to see if the results are accurate or recent enough for your purpose. If not you should request location updates using requestLocationUpdates().
This blog post contains everything you need to know about writing code using location providers.
http://android-developers.blogspot.com/2011/06/deep-dive-into-location.html
Ok my first guess is that you are not giving location fix via command line or by using eclipse DDMS perpective. If this is problem go open DDMS perpecive and give latitude and longtiude you want and send it. So location will not be null from now on if this is the problem.
The following link may help you in understanding how to use emulator in finding the location. The last section of this page has that information.
http://developer.android.com/guide/topics/location/obtaining-user-location.html