[android] Android: Reverse geocoding - getFromLocation

I am trying to get an address based on the long/lat. it appears that something like this should work?

Geocoder myLocation = Geocoder(Locale.getDefault());
    List myList = myLocation.getFromLocation(latPoint,lngPoint,1);

The issue is that I keep getting : The method Geocoder(Locale) is undefined for the type savemaplocation

Any assistance would be helpful. Thank you.

Thanks, I tried the context, locale one first, and that failed and was looking at some of the other constructors (I had seen one that had mentioned just locale). Regardless,

It did not work, as I am still getting : The method Geocoder(Context, Locale) is undefined for the type savemaplocation

I do have : import android.location.Geocoder;

Use this

Geocoder geocoder = new Geocoder(this, Locale.getDefault());
List<Address> addresses = geocoder.getFromLocation(lat, lng, 1);

The reason for this is the non-existent Backend Service:

The Geocoder class requires a backend service that is not included in the core android framework. The Geocoder query methods will return an empty list if there no backend service in the platform.

Use this

Geocoder geocoder = new Geocoder(this, Locale.getDefault());
List<Address> addresses = geocoder.getFromLocation(lat, lng, 1);

Well, I am still stumped. So here is more code.

Before I leave my map, I call SaveLocation(myMapView,myMapController); This is what ends up calling my geocoding information.

But since getFromLocation can throw an IOException, I had to do the following to call SaveLocation

try
{
    SaveLocation(myMapView,myMapController);
}
catch (IOException e) 
{
    // TODO Auto-generated catch block
    e.printStackTrace();
}

Then I have to change SaveLocation by saying it throws IOExceptions :

 public void SaveLocation(MapView mv, MapController mc) throws IOException{
    //I do this : 
    Geocoder myLocation = new Geocoder(getApplicationContext(), Locale.getDefault());   
    List myList = myLocation.getFromLocation(latPoint, lngPoint, 1);
//...
    }

And it crashes every time.

First get Latitude and Longitude using Location and LocationManager class. Now try the code below for Get the city,address info

double latitude = location.getLatitude();
double longitude = location.getLongitude();
Geocoder gc = new Geocoder(this, Locale.getDefault());
try {
    List<Address> addresses = gc.getFromLocation(lat, lng, 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());
    }

City info is now in sb. Now convert the sb to String (using sb.toString() ).

It looks like there's two things happening here.

1) You've missed the new keyword from before calling the constructor.

2) The parameter you're passing in to the Geocoder constructor is incorrect. You're passing in a Locale where it's expecting a Context.

There are two Geocoder constructors, both of which require a Context, and one also taking a Locale:

Geocoder(Context context, Locale locale)
Geocoder(Context context)

Solution

Modify your code to pass in a valid Context and include new and you should be good to go.

Geocoder myLocation = new Geocoder(getApplicationContext(), Locale.getDefault());   
List<Address> myList = myLocation.getFromLocation(latPoint, lngPoint, 1);

Note

If you're still having problems it may be a permissioning issue. Geocoding implicitly uses the Internet to perform the lookups, so your application will require an INTERNET uses-permission tag in your manifest.

Add the following uses-permission node within the manifest node of your manifest.

<uses-permission android:name="android.permission.INTERNET" />

I've heard that Geocoder is on the buggy side. I recently put together an example application that uses Google's http geocoding service to lookup location from lat/long. Feel free to check it out here

http://www.smnirven.com/?p=39

Well, I am still stumped. So here is more code.

Before I leave my map, I call SaveLocation(myMapView,myMapController); This is what ends up calling my geocoding information.

But since getFromLocation can throw an IOException, I had to do the following to call SaveLocation

try
{
    SaveLocation(myMapView,myMapController);
}
catch (IOException e) 
{
    // TODO Auto-generated catch block
    e.printStackTrace();
}

Then I have to change SaveLocation by saying it throws IOExceptions :

 public void SaveLocation(MapView mv, MapController mc) throws IOException{
    //I do this : 
    Geocoder myLocation = new Geocoder(getApplicationContext(), Locale.getDefault());   
    List myList = myLocation.getFromLocation(latPoint, lngPoint, 1);
//...
    }

And it crashes every time.

It looks like there's two things happening here.

1) You've missed the new keyword from before calling the constructor.

2) The parameter you're passing in to the Geocoder constructor is incorrect. You're passing in a Locale where it's expecting a Context.

There are two Geocoder constructors, both of which require a Context, and one also taking a Locale:

Geocoder(Context context, Locale locale)
Geocoder(Context context)

Solution

Modify your code to pass in a valid Context and include new and you should be good to go.

Geocoder myLocation = new Geocoder(getApplicationContext(), Locale.getDefault());   
List<Address> myList = myLocation.getFromLocation(latPoint, lngPoint, 1);

Note

If you're still having problems it may be a permissioning issue. Geocoding implicitly uses the Internet to perform the lookups, so your application will require an INTERNET uses-permission tag in your manifest.

Add the following uses-permission node within the manifest node of your manifest.

<uses-permission android:name="android.permission.INTERNET" />

Well, I am still stumped. So here is more code.

Before I leave my map, I call SaveLocation(myMapView,myMapController); This is what ends up calling my geocoding information.

But since getFromLocation can throw an IOException, I had to do the following to call SaveLocation

try
{
    SaveLocation(myMapView,myMapController);
}
catch (IOException e) 
{
    // TODO Auto-generated catch block
    e.printStackTrace();
}

Then I have to change SaveLocation by saying it throws IOExceptions :

 public void SaveLocation(MapView mv, MapController mc) throws IOException{
    //I do this : 
    Geocoder myLocation = new Geocoder(getApplicationContext(), Locale.getDefault());   
    List myList = myLocation.getFromLocation(latPoint, lngPoint, 1);
//...
    }

And it crashes every time.

It looks like there's two things happening here.

1) You've missed the new keyword from before calling the constructor.

2) The parameter you're passing in to the Geocoder constructor is incorrect. You're passing in a Locale where it's expecting a Context.

There are two Geocoder constructors, both of which require a Context, and one also taking a Locale:

Geocoder(Context context, Locale locale)
Geocoder(Context context)

Solution

Modify your code to pass in a valid Context and include new and you should be good to go.

Geocoder myLocation = new Geocoder(getApplicationContext(), Locale.getDefault());   
List<Address> myList = myLocation.getFromLocation(latPoint, lngPoint, 1);

Note

If you're still having problems it may be a permissioning issue. Geocoding implicitly uses the Internet to perform the lookups, so your application will require an INTERNET uses-permission tag in your manifest.

Add the following uses-permission node within the manifest node of your manifest.

<uses-permission android:name="android.permission.INTERNET" />

First get Latitude and Longitude using Location and LocationManager class. Now try the code below for Get the city,address info

double latitude = location.getLatitude();
double longitude = location.getLongitude();
Geocoder gc = new Geocoder(this, Locale.getDefault());
try {
    List<Address> addresses = gc.getFromLocation(lat, lng, 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());
    }

City info is now in sb. Now convert the sb to String (using sb.toString() ).

I've heard that Geocoder is on the buggy side. I recently put together an example application that uses Google's http geocoding service to lookup location from lat/long. Feel free to check it out here

http://www.smnirven.com/?p=39

The reason for this is the non-existent Backend Service:

The Geocoder class requires a backend service that is not included in the core android framework. The Geocoder query methods will return an empty list if there no backend service in the platform.

It looks like there's two things happening here.

1) You've missed the new keyword from before calling the constructor.

2) The parameter you're passing in to the Geocoder constructor is incorrect. You're passing in a Locale where it's expecting a Context.

There are two Geocoder constructors, both of which require a Context, and one also taking a Locale:

Geocoder(Context context, Locale locale)
Geocoder(Context context)

Solution

Modify your code to pass in a valid Context and include new and you should be good to go.

Geocoder myLocation = new Geocoder(getApplicationContext(), Locale.getDefault());   
List<Address> myList = myLocation.getFromLocation(latPoint, lngPoint, 1);

Note

If you're still having problems it may be a permissioning issue. Geocoding implicitly uses the Internet to perform the lookups, so your application will require an INTERNET uses-permission tag in your manifest.

Add the following uses-permission node within the manifest node of your manifest.

<uses-permission android:name="android.permission.INTERNET" />

Here is a full example code using a Thread and a Handler to get the Geocoder answer without blocking the UI.

Geocoder call procedure, can be located in a Helper class

public static void getAddressFromLocation(
        final Location location, final Context context, final Handler handler) {
    Thread thread = new Thread() {
        @Override public void run() {
            Geocoder geocoder = new Geocoder(context, Locale.getDefault());   
            String result = null;
            try {
                List<Address> list = geocoder.getFromLocation(
                        location.getLatitude(), location.getLongitude(), 1);
                if (list != null && list.size() > 0) {
                    Address address = list.get(0);
                    // sending back first address line and locality
                    result = address.getAddressLine(0) + ", " + address.getLocality();
                }
            } catch (IOException e) {
                Log.e(TAG, "Impossible to connect to Geocoder", e);
            } finally {
                Message msg = Message.obtain();
                msg.setTarget(handler);
                if (result != null) {
                    msg.what = 1;
                    Bundle bundle = new Bundle();
                    bundle.putString("address", result);
                    msg.setData(bundle);
                } else 
                    msg.what = 0;
                msg.sendToTarget();
            }
        }
    };
    thread.start();
}

Here is the call to this Geocoder procedure in your UI Activity:

getAddressFromLocation(mLastKownLocation, this, new GeocoderHandler());

And the handler to show the results in your UI:

private class GeocoderHandler extends Handler {
    @Override
    public void handleMessage(Message message) {
        String result;
        switch (message.what) {
        case 1:
            Bundle bundle = message.getData();
            result = bundle.getString("address");
            break;
        default:
            result = null;
        }
        // replace by what you need to do
        myLabel.setText(result);
    }   
}

Don't forget to put the following permission in your Manifest.xml

<uses-permission android:name="android.permission.INTERNET" />