Develop Reference

Show correct position on Google maps

I tried to implement Google positioning application to show users position on Google maps. I found this code on Stack Overflow, but the issue with this code is, it shows 500 meter or 1000 meter away from my correct position. Does anyone know how to fix it with exact location ? Any help would be highly appreciated.
This is my code
public class GoogleMapsActivity extends MapActivity {
public static final String TAG = "GoogleMapsActivity";
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.googlemap);
initComponents();
mapView.setBuiltInZoomControls(true);
mapView.setSatellite(true);
mapController = mapView.getController();
mapController.setZoom(16);
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
if (locationManager == null) {
Toast.makeText(GoogleMapsActivity.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(GoogleMapsActivity.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() {
#Override
public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
}
#Override
public void onProviderEnabled(String arg0) {
}
#Override
public void onProviderDisabled(String arg0) {
}
#Override
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(GoogleMapsActivity.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.googleMapview);
}
#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.pingreen);
canvas.drawBitmap(bmp, screenPts.x, screenPts.y - 24, null);
return true;
}
}
}

The easiest way is to use a MyLocationOverlay
https://developers.google.com/maps/documentation/android/reference/index?com/google/android/maps/MyLocationOverlay.html
Create and add to the maps overlays and it will position a marker exactly where the user is.
Something like
MyLocationOverlay myOvly = new MyLocationOverlay( this, mapView );
listOfOverlays.add( myOvly );
myOvly.enableMyLocation();
To Automatically zoom to position
myOvly.runOnFirstFix( new Runnable()
{
public void run()
{
mapController.animateTo( myOvly.getLocation() );
}
} );

find out current position in OSMdroid

I want to find map of my current position and update it when i move via showing a icon in OSMdroid.I find no problem when give specific location latitude and longitude and drawing icon but there are two errors when i give current location latitude and longitude.
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
mResourceProxy = new DefaultResourceProxyImpl(getApplicationContext());
setContentView(R.layout.main);
mMapView = (MapView) this.findViewById(R.id.mapview);
mMapView.setTileSource(TileSourceFactory.MAPNIK);
mMapView.setBuiltInZoomControls(true);
mMapView.setMultiTouchControls(true);
mapController = this.mMapView.getController();
mapController.setZoom(15);
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 = mLocMgr.getBestProvider(criteria, true);
Location location = mLocMgr.getLastKnownLocation(provider);
GeoPoint mypoint = new GeoPoint(location.getLatitude(), location.getLongitude()); // centre map here
GeoPoint mypointicon = new GeoPoint(location.getLatitude()+1000, location.getLongitude()+1000); // icon goes here
mapController.setCenter(mypoint);
mLocMgr = (LocationManager) getSystemService(LOCATION_SERVICE);
mLocMgr.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000, 100,
this);
ArrayList<OverlayItem> items=new ArrayList<OverlayItem>();
items.add(new OverlayItem("Here", "Sample Description", mypointicon));
this.mMyLocationOverlay = new ItemizedIconOverlay<OverlayItem>(items,
new ItemizedIconOverlay.OnItemGestureListener<OverlayItem>() {
#Override
public boolean onItemSingleTapUp(final int index,
final OverlayItem item) {
Toast.makeText(
MapOverLayGiveActivity.this,
"Item '" + item.mTitle, Toast.LENGTH_LONG).show();
return true; // We 'handled' this event.
}
#Override
public boolean onItemLongPress(final int index,
final OverlayItem item) {
Toast.makeText(
MapOverLayGiveActivity.this,
"Item '" + item.mTitle ,Toast.LENGTH_LONG).show();
return false;
}
}, mResourceProxy);
this.mMapView.getOverlays().add(this.mMyLocationOverlay);
mMapView.invalidate();
}
Error:
java.lang.NullPointerException
java.lang.RunTimeException
What's wrong in my code and how can i do that? thanks...

To follow location changes, implement LocationListener as below:
public class MyLocationListener implements LocationListener {
public void onLocationChanged(Location location) {
currentLocation = new GeoPoint(location);
displayMyCurrentLocationOverlay();
}
public void onProviderDisabled(String provider) {
}
public void onProviderEnabled(String provider) {
}
public void onStatusChanged(String provider, int status, Bundle extras) {
}
}
Inside onCreate method:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
locationListener = new MyLocationListener();
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListener);
Location location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if( location != null ) {
currentLocation = new GeoPoint(location.getLatitude(), location.getLongitude());
}
}
and displayMyCurrentLocationOverlay method:
private void displayMyCurrentLocationOverlay() {
if( currentLocation != null) {
if( currentLocationOverlay == null ) {
currentLocationOverlay = new ArrayItemizedOverlay(myLocationMarker);
myCurrentLocationOverlayItem = new OverlayItem(currentLocation, "My Location", "My Location!");
currentLocationOverlay.addItem(myCurrentLocationOverlayItem);
mapView.getOverlays().add(currentLocationOverlay);
} else {
myCurrentLocationOverlayItem.setPoint(currentLocation);
currentLocationOverlay.requestRedraw();
}
mapView.getController().setCenter(currentLocation);
}
}

You use this.myLocationOverlay - and because of that the osmDroid draw the current location - but for update the location you must use a location listener. Also, you must remove previous overlay from the map using mapView.getOverlays.clear() function
Well, let's say that you don't have acces to internet or GPS. In my opinion is safe to have a default point on the map.
In this code I check for a valid location. If is null, then I use DEFAULT values.
In my application I have no problems. I also draw a navigation path on the map, even if my location is changed.
{
Location location = null;
for (String provider : locationManager.getProviders(true))
{
location = locationManager.getLastKnownLocation(provider);
if (location != null)
{
//location.setLatitude(MAP_DEFAULT_LATITUDE);
//location.setLongitude(MAP_DEFAULT_LONGITUDE);
locationManager.requestLocationUpdates(provider, 0, 0, mUpdateHandler);
break;
}
}
//add car position
if (location == null)
{
location = new Location(LocationManager.GPS_PROVIDER);
location.setLatitude(MAP_DEFAULT_LATITUDE);
location.setLongitude(MAP_DEFAULT_LONGITUDE);
updateCarPosition(new GeoPoint(location));
}
}

if you test on Emulator then remember use DDMS to set your current lat & long. if you don't, the getLastKnownLocation will return null

android get current location name

I want to get the current location with name. I did coding for get current location (lat,lang), how can I show the relative place name?
(ie) 13.006389 - 80.2575 : Adyar,Chennai,India
LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, new LocationListener() {
public void onStatusChanged(String provider, int status, Bundle extras) {
// called when the location provider status changes. Possible status: OUT_OF_SERVICE, TEMPORARILY_UNAVAILABLE or AVAILABLE.
}
public void onProviderEnabled(String provider) {
// called when the location provider is enabled by the user
}
public void onProviderDisabled(String provider) {
// called when the location provider is disabled by the user. If it is already disabled, it's called immediately after requestLocationUpdates
}
public void onLocationChanged(Location location) {
double latitute = location.getLatitude();
double longitude = location.getLongitude();
// do whatever you want with the coordinates
}
});

This will convert the lat & lng into String Address and i have set it in the text field for your example. This is done by using the concept of Reverse Geocoding & there is a class called Geocoder in Android.
// Write the location name.
//
try {
Geocoder geo = new Geocoder(this.getApplicationContext(), Locale.getDefault());
List<Address> addresses = geo.getFromLocation(latitude, longitude, 1);
if (addresses.isEmpty()) {
yourtextboxname.setText("Waiting for Location");
}
else {
yourtextboxname.setText(addresses.get(0).getFeatureName() + ", " + addresses.get(0).getLocality() +", " + addresses.get(0).getAdminArea() + ", " + addresses.get(0).getCountryName());
}
}

Here is code to get current location and draw it on Google Maps
public class Showmap extends MapActivity {
private MapView mapView;
private MapController mapController;
private LocationManager locationManager;
private LocationListener locationListener;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.showmap);
LocationManager locationManager = (LocationManager)
getSystemService(Context.LOCATION_SERVICE);
locationListener = new GPSLocationListener();
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0,
0, locationListener);
mapView = (MapView) findViewById(R.id.mapView);
// enable Street view by default
mapView.setStreetView(true);
// enable to show Satellite view
// mapView.setSatellite(true);
// enable to show Traffic on map
// mapView.setTraffic(true);
mapView.setBuiltInZoomControls(true);
mapController = mapView.getController();
mapController.setZoom(16);
}
protected boolean isRouteDisplayed() {
return false;
}
private class GPSLocationListener implements LocationListener {
#Override
public void onLocationChanged(Location location) {
if (location != null) {
GeoPoint point = new GeoPoint(
(int) (location.getLatitude() * 1E6),
(int) (location.getLongitude() * 1E6));
mapController.animateTo(point);
mapController.setZoom(16);
// add marker
MapOverlay mapOverlay = new MapOverlay();
mapOverlay.setPointToDraw(point);
List<Overlay> listOfOverlays = mapView.getOverlays();
listOfOverlays.clear();
listOfOverlays.add(mapOverlay);
String address = ConvertPointToLocation(point);
Toast.makeText(getBaseContext(), address, Toast.LENGTH_SHORT)
.show();
mapView.invalidate();
}
}
public String ConvertPointToLocation(GeoPoint point) {
String address = "";
Geocoder geoCoder = new Geocoder(getBaseContext(),
Locale.getDefault());
try {
List<Address> addresses = geoCoder.getFromLocation(
point.getLatitudeE6() / 1E6,
point.getLongitudeE6() / 1E6, 1);
if (addresses.size() > 0) {
for (int index = 0; index < addresses.get(0)
.getMaxAddressLineIndex(); index++)
address += addresses.get(0).getAddressLine(index) + " ";
Log.i(address, address);
}
} catch (IOException e) {
e.printStackTrace();
}
return address;
}
#Override
public void onProviderDisabled(String provider) {}
#Override
public void onProviderEnabled(String provider) {}
#Override
public void onStatusChanged(String provider,int status,Bundle extras){}
}
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);
// convert point to pixels
Point screenPts = new Point();
mapView.getProjection().toPixels(pointToDraw, screenPts);
// add marker
Bitmap bmp = BitmapFactory.decodeResource(getResources(),
R.drawable.marker);
// 24 is the height of image
canvas.drawBitmap(bmp, screenPts.x, screenPts.y - 24, null);
return true;
}
}
}

Use reverse geocoding,feed the latitude and longitude and get the address.
Geocoder geocoder = new Geocoder(this, Locale.ENGLISH);
try {
List<Address> addresses = geocoder.getFromLocation(LATITUDE, LONGITUDE, 1);
if(addresses != null) {
Address returnedAddress = addresses.get(0);
StringBuilder strReturnedAddress = new StringBuilder("Address:\n");
for(int i=0; i<returnedAddress.getMaxAddressLineIndex(); i++) {
strReturnedAddress.append(returnedAddress.getAddressLine(i)).append("\n");
}
myAddress.setText(strReturnedAddress.toString());
}
else{
myAddress.setText("No Address returned!");
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
myAddress.setText("Canont get Address!");
}

The phrase you're looking for is "Reverse Geocoding". Another question on StackOverflow discusses the same topic- You can use that one's selected answer :)

This is only for Hint add your code !
public void onLocationChanged(Location location) {
// TODO Auto-generated method stub
if (location != null) {
System.out.println("in onlocationchanged");
String locationString=location.convert(location.getLatitude(),1);
Toast.makeText(this,"locationString=="+locationString, Toast.LENGTH_LONG).show();
double lat = location.getLatitude();
double lng = location.getLongitude();
String currentLocation = "The location is changed to Lat: " + lat + " Lng: " + lng;
Toast.makeText(this,currentLocation, Toast.LENGTH_LONG).show();
use this two method
public double getLattitude() {
return lattitude;
}
}
public double getLongitude() {
return longitude;

public class MainActivity extends AppCompatActivity {
double latitude, longitude;
private TextView tvLocation;
private Button btnGetLocation;
private FusedLocationProviderClient locationProviderClient;
private Geocoder geocoder;
private List<Address> addresses;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
requestPermission();
locationProviderClient = LocationServices.getFusedLocationProviderClient(this);
tvLocation = findViewById(R.id.tv_location);
geocoder = new Geocoder(MainActivity.this, Locale.getDefault());
btnGetLocation = findViewById(R.id.btn_location);
btnGetLocation.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (ActivityCompat.checkSelfPermission(MainActivity.this, ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
locationProviderClient.getLastLocation().addOnSuccessListener(MainActivity.this, new OnSuccessListener<Location>() {
#Override
public void onSuccess(Location location) {
if (location != null) {
tvLocation.setText(location.toString());
latitude = location.getLatitude();
longitude = location.getLongitude();
try {
addresses = geocoder.getFromLocation(latitude, longitude, 1);
String addressLine1 = addresses.get(0).getAddressLine(0);
Log.e("line1", addressLine1);
String city = addresses.get(0).getLocality();
Log.e("city", city);
String state = addresses.get(0).getAdminArea();
Log.e("state", state);
String pinCode = addresses.get(0).getPostalCode();
Log.e("pinCode", pinCode);
String fullAddress = addressLine1 + ", " + city + ", " + state + ", " + pinCode;
tvLocation.setText(fullAddress);
} catch (IOException e) {
e.printStackTrace();
Log.e("MainActivity", e.getMessage());
}
}
}
});
}
});
}
private void requestPermission() {
ActivityCompat.requestPermissions(this, new String[]{ACCESS_FINE_LOCATION}, 1);
}
}

Here Is my code to get the current country Name.
private String getCountry() {
String country_name = null;
LocationManager lm = (LocationManager)getApplicationContext().getSystemService(Context.LOCATION_SERVICE);
Geocoder geocoder = new Geocoder(getApplicationContext());
for(String provider: lm.getAllProviders()) {
#SuppressWarnings("ResourceType") Location location = lm.getLastKnownLocation(provider);
if(location!=null) {
try {
List<Address> addresses = geocoder.getFromLocation(location.getLatitude(), location.getLongitude(), 1);
if(addresses != null && addresses.size() > 0) {
country_name =addresses.get(0).getCountryName();
return country_name;
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
Toast.makeText(getApplicationContext(), country_name, Toast.LENGTH_LONG).show();
return null;
}
But don't forget to add this permission in the manifest file.
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>

Android,StreetView not showing correctly on my device Htc Desire

I have an HTC desire and am trying to write an app to show my current location.
I have managed to write the app and to show where I am. But I am only able to see my location in satelite view. When I try and only get the streetView the map appears blank and there are no streets shown at all.
Here is the code that I am trying to use for getting the streetView to show.
public class FindMeInMap extends MapActivity {
#Override
protected boolean isRouteDisplayed() {
return false;
}
MapController mapController;
MyPositionOverlay positionOverlay;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
MapView myMapView = (MapView)findViewById(R.id.theMapView);
myMapView.displayZoomControls(true);
myMapView.setBuiltInZoomControls(true);
mapController = myMapView.getController();
myMapView.setSatellite(false);
myMapView.setStreetView(true);
myMapView.displayZoomControls(true);
myMapView.setTraffic(true);
// Add the MyPositionOverlay
positionOverlay = new MyPositionOverlay();
List<Overlay> overlays = myMapView.getOverlays();
overlays.add(positionOverlay);
LocationManager locationManager;
String context = Context.LOCATION_SERVICE;
locationManager = (LocationManager)getSystemService(context);
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 = locationManager.getBestProvider(criteria, true);
Location location = locationManager.getLastKnownLocation(provider);
updateWithNewLocation(location);
locationManager.requestLocationUpdates(provider, 2000, 10,
locationListener);
}
private 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 updateWithNewLocation(Location location) {
String latLongString;
TextView myLocationText;
myLocationText = (TextView)findViewById(R.id.myLocationText);
String addressString = "No address found";
if (location != null) {
// Update my location marker
positionOverlay.setLocation(location);
// Update the map location.
Double geoLat = location.getLatitude()*1E6;
Double geoLng = location.getLongitude()*1E6;
GeoPoint point = new GeoPoint(geoLat.intValue(),
geoLng.intValue());
mapController.animateTo(point);
mapController.setZoom(17);
double lat = location.getLatitude();
double lng = location.getLongitude();
latLongString = "Lat:" + lat + "\nLong:" + lng;
double latitude = location.getLatitude();
double longitude = location.getLongitude();
Geocoder gc = new Geocoder(this, Locale.getDefault());
try {
List<Address> addresses = gc.getFromLocation(latitude,
longitude, 1);
StringBuilder sb = new StringBuilder();
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");
sb.append(address.getPostalCode()).append("\n");
sb.append(address.getCountryName());
}
addressString = sb.toString();
} catch (IOException e) {}
} else {
latLongString = "No location found";
}
myLocationText.setText("Your Current Position is:\n" +
latLongString + "\n" + addressString);
}
}
Can anyone spot my problem and tell me why I cannot see this working on my Desire? I tried the same code on the emulator and it works fine, just not on the phone ?!?
Thanks in Advance!

Make the following changes:
myMapView.setSatellite(false);
myMapView.setStreetView(true);
myMapView.setBuiltInZoomControls(true);
myMapView.postInvalidate();

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)
{
}
}
}
});