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LocationManager generating errorin code

this is my code in android and is showing error. I dont know what is wrong but i am certaqin it has to do something with LocationManager because until that line it works fine.
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.d("Exception", "Something gone wrong !! ");
/*after this line it shows error */
LocationManager lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
double longitude = location.getLongitude();
double latitude = location.getLatitude();
All i want right now is to display value of longitude and latitude so that i can be sure code is good till here.

Declate this variable
Location loc;
Write this code in Oncreate() method
LocationManager mlocManager =(LocationManager)getSystemService(Context.LOCATION_SERVICE);
LocationListener mlocListener = new MyLocationListener();
mlocManager.requestLocationUpdates( LocationManager.GPS_PROVIDER, 0, 0, mlocListener);
Then Write
loc.getLatitude();
loc.getLongitude();
Now you can use the value of latitude and longitude... :-)

Use Below Code Snippet
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
/* Use the LocationManager class to obtain GPS locations */
LocationManager mlocManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
LocationListener mlocListener = new MyLocationListener();
mlocManager.requestLocationUpdates( LocationManager.GPS_PROVIDER, 0, 0, mlocListener);
}
/* Class My Location Listener */
public class MyLocationListener implements LocationListener
{
#Override
public void onLocationChanged(Location loc)
{
loc.getLatitude();
loc.getLongitude();
String Text = "My current location is: " +
"Latitud = " + loc.getLatitude() +
"Longitud = " + loc.getLongitude();
Toast.makeText( getApplicationContext(), Text, Toast.LENGTH_SHORT).show();
}
#Override
public void onProviderDisabled(String provider)
{
Toast.makeText( getApplicationContext(), "Gps Disabled", Toast.LENGTH_SHORT ).show();
}
#Override
public void onProviderEnabled(String provider)
{
Toast.makeText( getApplicationContext(), "Gps Enabled", Toast.LENGTH_SHORT).show();
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras)
{
}
}
Check Below Line in Manifest file
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>

My current location always returns null. How can I fix this?

I am trying to find my current location for an android project. When the application is loaded my current location is always null. I have set up the permissions in the manifest etc. When I find the current location I intend to use the coordinates to find distances to other locations on the map. My code snippet is below. Why do I always get a null value?
locMan = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Criteria crit = new Criteria();
towers = locMan.getBestProvider(crit, false);
location = locMan.getLastKnownLocation(towers);
if (location != null) {
System.out.println("Location is not null!");
lat = (int) (location.getLatitude() *1E6);
longi = (int) (location.getLongitude() * 1E6);
GeoPoint ourLocation = new GeoPoint(lati, longi);
OverlayItem overlayItem = new OverlayItem(ourLocation, "1st String",
"2nd String");
CustomPinpoint custom = new CustomPinpoint(d, MainMap.this);
custom.insertPinpoint(overlayItem);
overlayList.add(custom);
overlayList.clear();
} else {
System.out.println("Location is null! " + towers);
Toast.makeText(MainMap.this, "Couldn't get provider",Toast.LENGTH_SHORT)
.show();
}

getLastKnownLocation() uses the location(s) previously found by other applications. if no application has done this, then getLastKnownLocation() will return null.
One thing you can do to your code to have a better chance at getting as last known location- iterate over all of the enabled providers, not just the best provider. For example,
private Location getLastKnownLocation() {
List<String> providers = mLocationManager.getProviders(true);
Location bestLocation = null;
for (String provider : providers) {
Location l = mLocationManager.getLastKnownLocation(provider);
ALog.d("last known location, provider: %s, location: %s", provider,
l);
if (l == null) {
continue;
}
if (bestLocation == null
|| l.getAccuracy() < bestLocation.getAccuracy()) {
ALog.d("found best last known location: %s", l);
bestLocation = l;
}
}
if (bestLocation == null) {
return null;
}
return bestLocation;
}
If your app can't deal without having a location, and if there's no last known location, you will need to listen for location updates. You can take a look at this class for an example,
https://github.com/farble1670/autobright/blob/master/src/org/jtb/autobright/EventService.java
See the method onStartCommand(), where it checks if the network provider is enabled. If not, it uses last known location. If it is enabled, it registers to receive location updates.

if u find current location of devices the use following method in main class
public void find_Location(Context con) {
Log.d("Find Location", "in find_location");
this.con = con;
String location_context = Context.LOCATION_SERVICE;
locationManager = (LocationManager) con.getSystemService(location_context);
List<String> providers = locationManager.getProviders(true);
for (String provider : providers) {
locationManager.requestLocationUpdates(provider, 1000, 0,
new LocationListener() {
public void onLocationChanged(Location location) {}
public void onProviderDisabled(String provider) {}
public void onProviderEnabled(String provider) {}
public void onStatusChanged(String provider, int status,
Bundle extras) {}
});
Location location = locationManager.getLastKnownLocation(provider);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
addr = ConvertPointToLocation(latitude, longitude);
String temp_c = SendToUrl(addr);
}
}
}
And Add User Permission method in your manifest file
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>

Try this this will not give you null current location
class GetLastLocation extends TimerTask {
LocationManager mlocManager = (LocationManager)
getSystemService(Context.LOCATION_SERVICE);
LocationListener mlocListenerTmp = new CustomLocationListener();
private final Handler mLocHandler;
public GetLastLocation(Handler mLocHandler) {
this.mLocHandler = mLocHandler;
}
#Override
public void run() {
timer.cancel();
mlocManager.removeUpdates(mlocListenerTmp);
Location location = mlocManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
{
if (mlocListenerTmp != null) {
mlocManager.removeUpdates(mlocListenerTmp);
}
currentLocation = location;
}
if (location != null) {
String message = String.format(
"Location \n Longitude: %1$s \n Latitude: %2$s",
location.getLongitude(), location.getLatitude());
Log.d("loc", " :" + message);
Bundle b = new Bundle();
{
b.putBoolean("locationRetrieved", true);
{
Message msg = Message.obtain();
{
msg.setData(b);
mLocHandler.sendMessage(msg);
}
}
}
} else {
Log.d(
"loc",
":No GPS or network signal please fill the location manually!");
location = mlocManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
currentLocation = location;
Bundle b = new Bundle();
{
b.putBoolean("locationRetrieved", true);
{
Message msg = Message.obtain();
{
msg.setData(b);
mLocHandler.sendMessage(msg);
}
}
}
} else {
Bundle b = new Bundle();
{
b.putBoolean("locationRetrieved", false);
{
Message msg = Message.obtain();
{
msg.setData(b);
mLocHandler.sendMessage(msg);
}
}
}
}
}
}
}
call it like this
timer.schedule(new GetLastLocation(mLocHandler), 3000);
and the customLocationclass is as follows
public class CustomLocationListener implements LocationListener {
#Override
public void onLocationChanged(Location loc) {
loc.getLatitude();
loc.getLongitude();
currentLocation = loc;
String Text = "My current location is: " + "Latitud = "
+ loc.getLatitude() + "Longitud = " + loc.getLongitude();
Log.d("loc", "onLocationChanged" + Text);
}
#Override
public void onProviderDisabled(String provider) {}
#Override
public void onProviderEnabled(String provider) {}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {}
}

If you are trying it out in a marshmallow device, try enabling location permission for your app manually.

turn on your GPS by using below method. it helps you to show your current location without any ERROR. call it in onCreate
public void displayLocationSettingsRequest(Context context, int requestCode) {
GoogleApiClient googleApiClient = new GoogleApiClient.Builder(context)
.addApi(LocationServices.API).build();
googleApiClient.connect();
LocationRequest locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(10000);
locationRequest.setFastestInterval(10000 / 2);
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder().addLocationRequest(locationRequest);
builder.setAlwaysShow(true);
PendingResult<LocationSettingsResult> result = LocationServices.SettingsApi.checkLocationSettings(googleApiClient, builder.build());
result.setResultCallback(result1 -> {
final Status status = result1.getStatus();
if (status.getStatusCode() == LocationSettingsStatusCodes.RESOLUTION_REQUIRED)
try {
status.startResolutionForResult((Activity) context, requestCode);
} catch (IntentSender.SendIntentException ignored) {
}
});

If you are getting a null error with your provider list, change...
List<String> providers = mLocationManager.getProviders(true);
to...
List<String> providers = locationManager.getAllProviders();
This worked for me, and make sure that you have the following in your AndroidManifest.xml file...
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

Have you tried reversing the code? For example, if(location==null) then print that location is null, and else print location is not null. I got that problem once before and that seemed to have fixed it (i don't know why). Try that.
If that doesn't work, perhaps the google maps API is returning the null value, in which case its a problem with the GM-API or with the call method. Any of these could be the problem.

How to get my current longitude and latitude from my Android device

I am using this code. but getting null in longitude and latitude.
LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);

Take a look at this tutorial: A Deep Dive Into Location
Basically, if you want to get the approximate location using the last known location, you should iterate through all the possible providers with a loop like this:
List<String> matchingProviders = locationManager.getAllProviders();
for (String provider: matchingProviders) {
Location location = locationManager.getLastKnownLocation(provider);
if (location != null) {
float accuracy = location.getAccuracy();
long time = location.getTime();
if ((time > minTime && accuracy < bestAccuracy)) {
bestResult = location;
bestAccuracy = accuracy;
bestTime = time;
}
else if (time < minTime &&
bestAccuracy == Float.MAX_VALUE && time > bestTime){
bestResult = location;
bestTime = time;
}
}
}

You can use the LocationManager. See the example:
LocationManager lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
double longitude = location.getLongitude();
double latitude = location.getLatitude();
And place it in Manisfest:
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

did you added
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
Permission to manifest file

Try This
public class LocationDemo extends Activity implements LocationListener {
private static final String TAG = "LocationDemo";
private static final String[] S = { "Out of Service",
"Temporarily Unavailable", "Available" };
private TextView output;
private LocationManager locationManager;
private String bestProvider;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Get the output UI
output = (TextView) findViewById(R.id.output);
// Get the location manager
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
// List all providers:
List<String> providers = locationManager.getAllProviders();
for (String provider : providers) {
printProvider(provider);
}
Criteria criteria = new Criteria();
bestProvider = locationManager.getBestProvider(criteria, false);
output.append("\n\nBEST Provider:\n");
printProvider(bestProvider);
output.append("\n\nLocations (starting with last known):");
Location location = locationManager.getLastKnownLocation(bestProvider);
printLocation(location);
}
/** Register for the updates when Activity is in foreground */
#Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(bestProvider, 20000, 1, this);
}
/** Stop the updates when Activity is paused */
#Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
public void onLocationChanged(Location location) {
printLocation(location);
}
public void onProviderDisabled(String provider) {
// let okProvider be bestProvider
// re-register for updates
output.append("\n\nProvider Disabled: " + provider);
}
public void onProviderEnabled(String provider) {
// is provider better than bestProvider?
// is yes, bestProvider = provider
output.append("\n\nProvider Enabled: " + provider);
}
public void onStatusChanged(String provider, int status, Bundle extras) {
output.append("\n\nProvider Status Changed: " + provider + ", Status="
+ S[status] + ", Extras=" + extras);
}
private void printProvider(String provider) {
LocationProvider info = locationManager.getProvider(provider);
output.append(info.toString() + "\n\n");
}
private void printLocation(Location location) {
if (location == null)
output.append("\nLocation[unknown]\n\n");
else
output.append("\n\n" + location.toString());
}
}
// main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ScrollView android:layout_width="wrap_content"
android:layout_height="wrap_content">
<TextView android:id="#+id/output" android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</ScrollView>
</LinearLayout>

implementation 'com.google.android.gms:play-services-location:11.6.0'
public class LocationExample Eextends AppCompatActivity implements LocationListener {
double latitude, longitude;
LocationManager locationManager;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
getLocation()
}
void getLocation() {
locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
boolean isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (isNetworkEnabled) {
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_COARSE);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
//GlobalToast.toastMessage(this, "please provide location permission.");
return;
}
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 1, 400, this);
} else {
boolean isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
if (isGPSEnabled) {
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1, 400, this);
}
}
}
#Override
public void onLocationChanged(Location location) {
latitude = location.getLatitude();
longitude = location.getLongitude();
Log.d("location", "change");
Log.d("latitude", String.valueOf(latitude));
Log.d("longitude", String.valueOf(longitude));
}
#Override
public void onStatusChanged(String s, int i, Bundle bundle) {
}
#Override
public void onProviderEnabled(String s) {
}
#Override
public void onProviderDisabled(String s) {
Toast.makeText(getApplicationContext(), "Please Enable GPS and Internet", Toast.LENGTH_SHORT).show();
}
}

Unable to get latitude and longitude from android

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

In ANDROID, How to get a current position and tracking in map using GPS without giving any location in a program?

I am new to android, can anyone help me for my question....
How to get a current position and tracking in map using GPS without giving any location in a program?????

You want the easy way out ! Use MyLocationOverlay object. you can get the current location by calling the method getLastFix(); . To enable tracking use enableMyLocation(). To add this object to the map you need to add it to your map overlays.
MyLocationOverlay currLoc=new MyLocationOverlay(context,mapKey);
mapView.getAllOverlays.add(currLoc);
currLoc.enableMyLocation();
Location myLastLocation=currLoc.getLastFix();
currLoc.enableCompass();
Do make sure, in onPause() you do this :
currLoc.disableMyLocation(); //to save battery.
you can resume updates in onResume() by calling currLoc.enableMyLocation();
This is the easiest way I could find! and it is quite accurate too

Try ;
String m_BestProvider;
LocationManager m_LocationManager;
LocationListener m_LocationListener = null;
Location m_Location = null;
m_LocationManager = (LocationManager) m_Context.getSystemService(Context.LOCATION_SERVICE);
Criteria c = new Criteria();
c.setAccuracy(Criteria.ACCURACY_COARSE);
c.setAltitudeRequired(false);
c.setBearingRequired(false);
c.setSpeedRequired(false);
c.setCostAllowed(true);
c.setPowerRequirement(Criteria.POWER_HIGH);
m_BestProvider = m_LocationManager.getBestProvider(c, false);
// Define a listener that responds to location updates
m_LocationListener = new LocationListener() {
public void onLocationChanged(Location location) {
// Called when a new location is found by the network location provider.
}
public void onStatusChanged(String provider, int status, Bundle extras) {}
public void onProviderEnabled(String provider) {}
public void onProviderDisabled(String provider) {}
};
m_LocationManager.requestLocationUpdates(m_BestProvider, 0, 0, m_LocationListener);
m_Location = m_LocationManager.getLastKnownLocation(m_BestProvider);
Systme.out.println(m_Location.getLatitude() "," +m_Location.getLongitude());
Add in AndriodManifest.xml:
<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"/>

public class GPSLocationBased extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.locationbased);
LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
LocationListener ll = new Mylocationlistener();
// ---Get the status of GPS---
boolean isGPS = lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
// If GPS is not enable then it will be on
if(!isGPS)
{
Intent intent = new Intent("android.location.GPS_ENABLED_CHANGE");
intent.putExtra("enabled", true);
sendBroadcast(intent);
}
//<--registers the current activity to be notified periodically by the named provider. Periodically,
//the supplied LocationListener will be called with the current Location or with status updates.-->
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, ll);
}
/**
*Mylocationlistener class will give the current GPS location
*with the help of Location Listener interface
*/
private class Mylocationlistener implements LocationListener {
#Override
public void onLocationChanged(Location location) {
if (location != null) {
// ---Get current location latitude, longitude, altitude & speed ---
Log.d("LOCATION CHANGED", location.getLatitude() + "");
Log.d("LOCATION CHANGED", location.getLongitude() + "");
float speed = location.getSpeed();
double altitude = location.getAltitude();
Toast.makeText(GPSLocationBased.this,"Latitude = "+
location.getLatitude() + "" +"Longitude = "+ location.getLongitude()+"Altitude = "+altitude+"Speed = "+speed,
Toast.LENGTH_LONG).show();
}
}
#Override
public void onProviderDisabled(String provider) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
}
}
Through this code u will get ur lat and long.
and u may use it on ur gmap.
this code also start gps functionality problematically. Hope this will help u.. All the best :)