android - I want to use GPS but my code uses WiFi..!!! why?

Question

I have written the following code that returns my current location address. But i can get these values only if the my Wifi is switched on manually. but i want to switch on the Gps and get my address from GPS and not from Wifi. Someone please tell me what is to be modified in this code to do so. Following is the code am using to locate my current address. Thanks in advance.

public String myloc()
{ 
    criteria = new Criteria();
    criteria.setAccuracy(Criteria.ACCURACY_FINE);
    criteria.setAltitudeRequired(false);
    criteria.setBearingRequired(false);
    criteria.setCostAllowed(true);
    criteria.setPowerRequirement(Criteria.POWER_LOW);

    locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
    String provider = locationManager.getBestProvider(criteria, true);

    // Update the GUI with the last known 
    Location location = locationManager.getLastKnownLocation(provider);

    if(location!=null)
    {
        double lat = location.getLatitude();
        double lng = location.getLongitude();
        latLongString = "Lat:" + lat + "
Long:" + lng;

        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);
              sb.append(address.getAddressLine(0)).append("
");
              sb.append(address.getLocality()).append("
");
              sb.append(address.getAdminArea()).append("
");
              sb.append(address.getCountryName());

            }
            addressString = sb.toString();
        } 
        catch (IOException e)
        {

        }
    } 
    else 
    {
        latLongString = "No location found";
    }

    return addressString;
}

Answer 1

It may be helpful to you.

Below is MyLocation.Java file

import java.util.Timer;
import java.util.TimerTask;
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;

public class MyLocation {
    Timer timer1;
    LocationManager lm;
    LocationResult locationResult;
    boolean gps_enabled=false;
    boolean network_enabled=false;

    public boolean getLocation(Context context, LocationResult result)
    {
        //I use LocationResult callback class to pass location value from MyLocation to user code.
        locationResult=result;
        if(lm==null)
            lm = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);

        //exceptions will be thrown if provider is not permitted.
        try{gps_enabled=lm.isProviderEnabled(LocationManager.GPS_PROVIDER);}catch(Exception ex){}
        try{network_enabled=lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);}catch(Exception ex){}

        //don't start listeners if no provider is enabled
        if(!gps_enabled && !network_enabled)
            return false;

        if(gps_enabled)
            lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps);
        if(network_enabled)
            lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListenerNetwork);
        timer1=new Timer();
        timer1.schedule(new GetLastLocation(), 60000);
        return true;
    }

    LocationListener locationListenerGps = new LocationListener() {
        public void onLocationChanged(Location location) {
            timer1.cancel();
            locationResult.gotLocation(location);
            lm.removeUpdates(this);
            lm.removeUpdates(locationListenerNetwork);
        }
        public void onProviderDisabled(String provider) {}
        public void onProviderEnabled(String provider) {}
        public void onStatusChanged(String provider, int status, Bundle extras) {}
    };

    LocationListener locationListenerNetwork = new LocationListener() {
        public void onLocationChanged(Location location) {
            timer1.cancel();
            locationResult.gotLocation(location);
            lm.removeUpdates(this);
            lm.removeUpdates(locationListenerGps);
        }
        public void onProviderDisabled(String provider) {}
        public void onProviderEnabled(String provider) {}
        public void onStatusChanged(String provider, int status, Bundle extras) {}
    };

    class GetLastLocation extends TimerTask {
        @Override
        public void run() {
             lm.removeUpdates(locationListenerGps);
             lm.removeUpdates(locationListenerNetwork);

             Location net_loc=null, gps_loc=null;
             if(gps_enabled)
                 gps_loc=lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
             if(network_enabled)
                 net_loc=lm.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);

             //if there are both values use the latest one
             if(gps_loc!=null && net_loc!=null){
                 if(gps_loc.getTime()>net_loc.getTime())
                     locationResult.gotLocation(gps_loc);
                 else
                     locationResult.gotLocation(net_loc);
                 return;
             }

             if(gps_loc!=null){
                 locationResult.gotLocation(gps_loc);
                 return;
             }
             if(net_loc!=null){
                 locationResult.gotLocation(net_loc);
                 return;
             }
             locationResult.gotLocation(null);
        }
    }

    public static abstract class LocationResult{
        public abstract void gotLocation(Location location);
    }
}

---

And now used this file in another Main class file

MyLocation myLocation = new MyLocation();

@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.splash);
        findCurrentLocation();

    }

private void findCurrentLocation() {
        myLocation.getLocation(this, locationResult);
    }

public LocationResult locationResult = new LocationResult() {

        @Override
        public void gotLocation(Location location) {
            // TODO Auto-generated method stub
            if (location != null) {
                String strloc  = location.getLatitude() + ","
                        + location.getLongitude();
            }
        }
    };

now Toast messge of "strloc".

Thanks, Nik...