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getFromLocation() returns null in Asynctask execute() method

I'm trying to make a weather app that uses Geocoder to get the current city, and then uses AsyncTask to get weather data from an api and then parse it. But when I input the current city into the AsyncTask execute() method, my app crashes:
private double latitude;
private double longitude;
String address;
LocationManager lm;
LocationListener ll;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
address = getAddress(latitude, longitude); // getAddress() is below
lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
ll = new myLocationListener();
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, ll);
}
private class myLocationListener implements LocationListener {
#Override
public void onLocationChanged(android.location.Location location) {
latitude = location.getLatitude();
longitude = location.getLongitude();
String address = getAddress(latitude, longitude);
Task task = new Task(); // Task extends AsyncTask
task.execute(new String[] { address });
}
#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
}
public String getAddress(double lat, double lon) {
Geocoder geocoder = new Geocoder(this, Locale.ENGLISH);
String ret = "";
try {
List<Address> addresses = geocoder.getFromLocation(
lat, lon, 10);
if (addresses != null) {
Address returnedAddress = addresses.get(0);
StringBuffer str = new StringBuffer();
str.append(returnedAddress.getLocality());
str.append(",");
str.append(returnedAddress.getCountryName());
ret = str.toString();
} else {
ret = "No Address returned!";
}
} catch (IOException e) { // TODO Auto-generated catch block
e.printStackTrace();
ret = "Can't get Address!";
}
return ret;
}
I know for a fact that my getAddress() method works like it's supposed to. When I hardcode a city and state into the address field, it works like a charm. However, when I call my getAddress() method and set it to address, and then input it into execute(), the app crashes and it says that getFromLocation() returned null. Why is this happening? Is it the order of my code? Thank you for all answers in advance.

Make sure your GPS is enabled and you are not testing from the emulator. The provider will return null if it is not enabled as per the documentation. Since you need the current location and probably you do not want updates I will recommend you use requestSingleUpdate(). A better option will be to use the new LocationClient Class that is part of Google Services; its fused provider gets the best Location available for you.

Logging location address to LogCat

A part of my app is attempting to update the location (using DDMS with an emulator in Eclipse) and then get the address to print to LogCat.
My code:
LocationManager locationManager;
String providerName = LocationManager.GPS_PROVIDER;
LocationProvider gpsProvider;
public void enable()
{
locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE); //Need to ask for this system service
Criteria criteria = new Criteria(); //Setting the criteria for the location provider
criteria.setAccuracy(Criteria.ACCURACY_FINE);
criteria.setPowerRequirement(Criteria.POWER_HIGH);
criteria.setAltitudeRequired(true);
criteria.setBearingRequired(true);
criteria.setSpeedRequired(true);
criteria.setCostAllowed(true);
String provider = LocationManager.GPS_PROVIDER;
int time = 5000; //Time in ms
int distance = 5; //Distance in meters
LocationListener myLocationListener = new LocationListener()
{
public void onLocationChanged(Location locations)
{
updateLocation(locations);
}
public void onProviderDisabled(String arg0)
{
// TODO Auto-generated method stub
}
public void onProviderEnabled(String arg0)
{
// TODO Auto-generated method stub
}
public void onStatusChanged(String arg0, int arg1, Bundle arg2)
{
// TODO Auto-generated method stub
}
};
locationManager.requestLocationUpdates(provider, time, distance, myLocationListener);
}
/////////////////////////////////////////////////////////////////////////////////
public void findLocation()
{
gpsProvider = locationManager.getProvider(providerName);
//String bestProvider = locationManager.getBestProvider(criteria, true);
Location locations = locationManager.getLastKnownLocation(providerName);
updateLocation(locations);
}
public void updateLocation(Location locations)
{
if (locations != null)
{
Geocoder geocoder = new Geocoder(getApplicationContext(), Locale.getDefault());
double latitude = locations.getLatitude();
double longitude = locations.getLongitude();
List<Address> addresses = null;
Geocoder GCoder = new Geocoder(this, Locale.getDefault());
try
{
addresses = GCoder.getFromLocation(latitude, longitude, 10);
Address first = addresses.get(0);
Log.d("ADDRESS", first.toString());
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
This, to me, should print the value "first" into LogCat but it doesn't seem to actually display anything.
I have the required permission in the manifest so that is not the issue.
Any help that can be provided is great, thank you.

Use this code
See Updated Code
LocationManager locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
String provider = locationManager.getBestProvider(new Criteria(), true);
Location locations = locationManager.getLastKnownLocation(provider);
List<String> providerList = locationManager.getAllProviders();
if(null!=locations && null!=providerList && providerList.size()>0){
double longitude = locations.getLongitude();
double latitude = locations.getLatitude();
Geocoder geocoder = new Geocoder(getApplicationContext(), Locale.getDefault());
try {
List<Address> listAddresses = geocoder.getFromLocation(latitude, longitude, 1);
if(null!=listAddresses&&listAddresses.size()>0){
String _Location = listAddresses.get(0).getAddressLine(1);
}
} catch (IOException e) {
e.printStackTrace();
}
}

Trouble calling and getting location in oncreate method from location listener android

i need your help regarding the location update in android. Following is my code for getting location update and it is working fine. But it returns invalid message body when i get the stored variable with location in oncreate method of main class. After thorough research it seems that the variable i called in oncreate method is empty. Can you please tell me how to get the address as it appears in onlocationChanged Method. Thank you!
Calling class with oncreate method:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listener = new Mylocation();
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, listener);
String address1= listener.getAddress();
{
sendSms(phone, message, false);
} catch (Exception e) {
Log.i("Error Is ", e.toString());
}
}
location class:
class Mylocation implements LocationListener{
double lat, lon;
static final String address="";
public void onLocationChanged(Location location)
{
//...
lat = location.getLatitude();
lon = location.getLongitude();
address = GetAddressDetail(lat, lon);
Log.i("Messge is", address); //working here
}
public String getAddress(){ //not returning the address
return address;
}
public String GetAddressDetail(Double lat2, Double lon2)
{
Geocoder geocoder = new Geocoder(MainActivity.this, Locale.ENGLISH);
try {
List<Address> addresses = geocoder.getFromLocation(lat2,lon2, 1);
if(addresses != null) {
Address returnedAddress = addresses.get(0);
StringBuilder strReturnedAddress = new StringBuilder("Address:");
for(int i=0; i<returnedAddress.getMaxAddressLineIndex(); i++) {
strReturnedAddress.append(returnedAddress.getAddressLine(i));
}
ret = strReturnedAddress.toString();
}
else{
ret = "No Address returned!";
}
}
return ret;
}
}

Make sure your variables are initialized properly. I don't see evidence of this in the question so I am just checking.
// Instantiation
Mylocation listener;
String phone;
String message;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Initialization
listener = new Mylocation(this);
phone = "";
message = "";
// These two lines aren't really necessary,
// this should be in your MyLocation class
//locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
//locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, listener);
// Add this line, we are going to initialize this class
// and make sure that address gets set
listener = new Mylocation();
String address1 = listener.getAddress();
try {
// If neither phone nor message is empty lets sendSms()
if (!phone.isEmpty() || !message.isEmpty()) {
sendSms(phone, message, false);
}
} catch (Exception e) {
Log.i("Error Is ", e.toString());
}
}
Change the String address to private and in the getter try return this.address;
class Mylocation implements LocationListener {
double lat, lon;
// Let's make this private so it can't be accessed directly,
// since you have the setter and getter.
private String address = "";
// Make sure you are overriding this method
#Override
public void onLocationChanged(Location location) {
/** ... */
lat = location.getLatitude();
lon = location.getLongitude();
address = GetAddressDetail(lat, lon);
Log.i("Messge is", address);
}
public String getAddress(){
return (address.isEmpty()) ? "Address not set" : this.address;
}
public String GetAddressDetail(Double lat2, Double lon2) {
Geocoder geocoder = new Geocoder(MainActivity.this, Locale.ENGLISH);
try {
List<Address> addresses = geocoder.getFromLocation(lat2,lon2, 1);
if(addresses != null) {
Address returnedAddress = addresses.get(0);
StringBuilder strReturnedAddress = new StringBuilder("Address:");
for(int i=0; i<returnedAddress.getMaxAddressLineIndex(); i++) {
strReturnedAddress.append(returnedAddress.getAddressLine(i));
}
ret = strReturnedAddress.toString();
}
else{
ret = "No Address returned!";
}
}
return ret;
}
}
Edit
I made changes to your code in my answer above, check the comments. I am also going to suggest additional methods for your MyLocation class:
class Mylocation implements LocationListener {
protected LocationManager locationManager;
private Context activityContext;
// The initializing method, this fires off first
// when a new instance of the class is created
public MyLocation(Context context) {
this.activityContext = context;
locationManager = (LocationManager) activityContext.getSystemService(LOCATION_SERVICE);
if (locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);) {
locationManager.requestLocationUpdates(
NETWORK_PROVIDER,
MIN_TIME,
MIN_DISTANCE,
this
);
}
getLocation();
}
private double lat;
private double lon;
public double getLat() {
return this.lat;
}
public double getLng() {
return this.lng;
}
public void getLocation() {
if (location == null) {
locationManager.requestLocationUpdates(NETWORK_PROVIDER, MIN_TIME, MIN_DISTANCE, this);
if (locationManager != null) {
location = locationManager.getLastKnownLocation(NETWORK_PROVIDER);
if (location != null) {
// Set the coordinate variables
lat = location.getLatitude();
lon = location.getLongitude();
Log.i("Network", "Lat: " + latitude + " / Lng: " + longitude);
}
}
}
}
}

You are calling getAdress directly after you set the locationmanager to probe for a location. The onLocationChanged method probably hasn't been called yet when you call getAddress this way. I would recommend changing it to something like below to make sure it has been called:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listener = new Mylocation();
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0,new LocationListener(){
#Override
public void onLocationChanged(Location location) {
//...
long lat = location.getLatitude();
long lon = location.getLongitude();
String address = GetAddressDetail(lat, lon);
//Do whatever you want to do with the address here, maybe add them to the message or something like that.
sendSms(phone, message, false);
}
});
}
public String GetAddressDetail(Double lat2, Double lon2)
{
Geocoder geocoder = new Geocoder(MainActivity.this, Locale.ENGLISH);
try {
List<Address> addresses = geocoder.getFromLocation(lat2,lon2, 1);
if(addresses != null) {
Address returnedAddress = addresses.get(0);
StringBuilder strReturnedAddress = new StringBuilder("Address:");
for(int i=0; i<returnedAddress.getMaxAddressLineIndex(); i++) {
strReturnedAddress.append(returnedAddress.getAddressLine(i));
}
ret = strReturnedAddress.toString();
}
else{
ret = "No Address returned!";
}
}
return ret;
}

reverse geocoding not working

i written following code to get current location. although I m testing it in emulator with different latitude and longitude. But it cant convert the lattitude and longitude in real location.
public class LocationFindingActivity extends Activity {
/** Called when the activity is first created. */
EditText et;
LocationManager locationManager;
String provider;
LocationListener locationListener;
Location currentLocation;
String addressString="";
String longlattString="";
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
et=(EditText)findViewById(R.id.locationTXT);
locationManager =(LocationManager) getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
criteria.setAltitudeRequired(false);
criteria.setBearingRequired(false);
criteria.setCostAllowed(true);
criteria.setPowerRequirement(Criteria.POWER_LOW);
provider = locationManager.getBestProvider(criteria, true);
currentLocation=locationManager.getLastKnownLocation(provider);
et.setText(addressString);
locationListener =new LocationListener() {
#Override
public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
// TODO Auto-generated method stub
}
#Override
public void onProviderEnabled(String arg0) {
// TODO Auto-generated method stub
}
#Override
public void onProviderDisabled(String arg0) {
// TODO Auto-generated method stub
}
#Override
public void onLocationChanged(Location arg0) {
// TODO Auto-generated method stub
updateWithNewLocation(currentLocation);
}
};
updateWithNewLocation(currentLocation);
locationManager.requestLocationUpdates(provider, 2000, 10,locationListener)
}
private void updateWithNewLocation(Location location) {
if (location != null)
{
double lat = location.getLatitude();
double lng = location.getLongitude();
longlattstring="Lattitude :"+lat+"Longitude :"+lng;
Geocoder gc = new Geocoder(this, Locale.getDefault());
try
{
List<Address> addresses = gc.getFromLocation(lat, lng, 1);
StringBuilder sb = new StringBuilder();
//Toast.makeText(this, "Problem1", 2000).show();
if (addresses.size() > 0)
{
Address address = addresses.get(0);
for (int i = 0; i < address.getMaxAddressLineIndex(); i++)
sb.append(address.getAddressLine(i)).append("\n");
sb.append(address.getLocality()).append("\n");
Toast.makeText(this, "Problem2", 2000).show();
sb.append(address.getPostalCode()).append("\n");
sb.append(address.getCountryName());
}
addressString = sb.toString();
}
catch (IOException e)
{
Toast.makeText(this, "Problem Catch", 2000).show();
}
}
else
{
addressString = "No location found";
}
et.setText(addressString);
}
}
I am getting problem in this line
List addresses = gc.getFromLocation(lat, lng, 1);
the statement doesn't return anything.

It's a known bug which they never fixed see service not avavilable.I think you will find that it works in the the API level 7 emulator.

using geocoder with myLocationOverlay

i try to get the current zip code from the longitude and latitude which MyLocationOverlay delivers and set this to a EditView on my Activity.
The Activity crashs when i try to get the longitude and latitude from MyLocationOverlay.
Whats wrong with this code?
Regards,
float
LogCat output: http://codepaste.net/vs6itk
Line 59 is the following line:
double currentLatitude = myLocationOverlay.getMyLocation().getLatitudeE6();
Here is my Code:
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.partner_suche);
final EditText tView = (EditText) findViewById(R.id.editTextPLZ);
final MapView mView = (MapView) findViewById(R.id.mapview);
mView.getController().setZoom(14);
List<Overlay> mapOverlays = mView.getOverlays();
myLocationOverlay = new MyCustomLocationOverlay(this, mView);
mapOverlays.add(myLocationOverlay);
myLocationOverlay.enableMyLocation();
myLocationOverlay.enableCompass();
myLocationOverlay.runOnFirstFix(new Runnable() {
public void run() {
mView.getController().animateTo(myLocationOverlay.getMyLocation());
}
});
Geocoder gc = new Geocoder(this, Locale.getDefault());
double currentLatitude = myLocationOverlay.getMyLocation().getLatitudeE6();
double currentLongitute = myLocationOverlay.getMyLocation().getLongitudeE6();
try
{
List<Address> addresses = gc.getFromLocation(currentLatitude, currentLongitute, 1);
if (addresses.size() > 0)
{
tView.setText(addresses.get(0).getLocality());
}
} catch (IOException e)
{
}
}
EDIT:
I created a LocationListener to get my current location. Now the part crashes where i try to run gc.getFromLocation(latitude, longitude, 1); I can't read the Exception? :/
LocationManager locationManager;
String context = Context.LOCATION_SERVICE;
locationManager = (LocationManager)getSystemService(context);
String provider = LocationManager.GPS_PROVIDER;
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){ }
};
locationManager.requestLocationUpdates(provider, 0, 0, locationListener);
private void updateWithNewLocation(Location location) {
final EditText tView = (EditText) findViewById(R.id.editTextPLZ);
double latitude = location.getLatitude();
double longitude = location.getLongitude();
Geocoder gc = new Geocoder(this, Locale.getDefault());
if (location != null) {
try
{
List<Address> addresses = gc.getFromLocation(latitude, longitude, 1);
if (addresses.size() > 0)
{
Address address = addresses.get(0);
for (int i = 0; i < address.getMaxAddressLineIndex(); i++){
tView.setText(address.getPostalCode());
}
}
} catch (Exception e)
{
}
}
}

If you are using an emulator API level 8 or 9, and getting the exception:
java.io.IOException: Service not Available
then it is a known bug, see service not available
It works OK on real devices and emulator level 7 though. ( You should probably put a trap on addresses being null too, though this won't make the geocoder work!)

Most likely the location being returned from
myLocationOverlay.getMyLocation()
or
Location location = locationManager.getLastKnownLocation(provider);
is NULL. Likely due to your application not yet having received a location fix, and having no previously saved locations.
Try moving the code block where you do the geocoding into your runnable that runs after receiving a fix. Like this:
myLocationOverlay.runOnFirstFix(new Runnable() {
public void run() {
Location loc = myLocationOverlay.getMyLocation();
if (loc != null) {
mView.getController().animateTo(loc);
Geocoder gc = new Geocoder(this, Locale.getDefault());
double currentLatitude = loc.getLatitudeE6();
double currentLongitute = loc.getLongitudeE6();
try
{
List<Address> addresses = gc.getFromLocation(currentLatitude, currentLongitute, 1);
if (addresses.size() > 0)
{
tView.setText(addresses.get(0).getLocality());
}
} catch (IOException e)
{
}
}
}
});