Threaded's Eclectic Blog

Here I describe the minimal code to retrieve a GPS location in the Google Android OS.

First up, a GPS location listener.

				
class GPSLocationListener implements LocationListener {

   public void onLocationChanged(Location location) {       
       double latitude = location.getLatitude();
       double longitude = location.getLongitude();
   }

   public void onProviderDisabled(String provider) {
       // TODO Auto-generated method stub
   }

   public void onProviderEnabled(String provider) {
       // TODO Auto-generated method stub 
   }

   public void onStatusChanged(String provider, int status, Bundle extras) {
       // TODO Auto-generated method stub 
   }  
}

			

Somewhere else, probably in the Activity you need to tie this listener in. Here is an onCreate from a minimal application's Activity .

				
  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
   
      super.onCreate(savedInstanceState);

      setContentView(R.layout.main);
    
      GPSLocationListener gpsLocationListener = new GPSLocationListener();
    
      LocationManager lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE);

      long minTime = 600000;
      float minDistance = 10;
  
      lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, minTime, minDistance, gpsLocationListener);
                    
  }

			

minTime is a request to the OS about how often to check the GPS location. If you set it less than 1 minute (60000) then you risk the battery going flat quickly because the GPS receiver will be on all the time. The number is just a request. The OS may request a fix more often, it may check less often.

minDistance is a request to trigger the listener when the device has moved by this distance.

You also need <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"></uses-permission>
in the applications AndroidManifest.xml file.

Labels: google android