problem in getting gps coordinates in android 2.1(Found Answer)

Question

I am having a problem in getting GPS coordinates in 2.1.

The code i am using right now is working well in 1.6 but when i test this same apk in 1.6 device is showing null values

plz help me to find a way to work with 2.1 devices also

Here is my code...

public class GpsLocator {

   private static String PROVIDER="gps";
   private LocationManager myLocationManager=null;

   public GpsLocator(Context context) {
      myLocationManager=(LocationManager)context.getSystemService(Context.LOCATION_SERVICE);
   }

   public void myOnresume() {
      myLocationManager.requestLocationUpdates(PROVIDER, 0,   0, onLocationChange);
   }

   public void myonPause() {
       myLocationManager.removeUpdates(onLocationChange);
   }

   public double getLatitude() {
      Location loc=myLocationManager.getLastKnownLocation(PROVIDER);
      if (loc==null) {
         return(0);
      }
      return(loc.getLatitude());
   }

   public double getLongitude() {
      Location loc=myLocationManager.getLastKnownLocation(PROVIDER);
      if (loc==null) {
         return(0);
      }

      return(loc.getLongitude());
   }

   LocationListener onLocationChange=new LocationListener() {

      public void onLocationChanged(Location location) {
      }

      public void onProviderDisabled(String provider) {
         // required for interface, not used
      }

      public void onProviderEnabled(String provider) {
         // required for interface, not used
      }

      public void onStatusChanged(String provider, int status,Bundle extras) {
         // required for interface, not used
      }
   };
}

in the manifest file i add permission for accessing file they are

<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" />

Answer 1

LocationManager.getLastKnownLocation does not guarantee that it will return a valid location. If a GPS fix hasn't been established yet, it will return null. The only reliable way to get an actual location is to use the LocationListener -interface. I see that you have defined a LocationListener, but aren't using it.

You need to modify your code so that it waits for the first call to onLocationChanged before you try to do anything with the location.

Answer 2

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){ }

};