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javaandroidclassgpslocationlistener

Android onLocationChanged and MainActivity class


I have the following code:

public class MyLocationListener implements LocationListener {


@Override
public void onLocationChanged(Location loc) {
    // called when the listener is notified with a location update from the GPS
    Log.d("Latitude", Double.toString(loc.getLatitude()));
    Log.d("Longitude", Double.toString(loc.getLongitude()));
}
@Override
public void onProviderDisabled(String provider) {
   // called when the GPS provider is turned off (user turning off the GPS on the phone)
}
@Override
public void onProviderEnabled(String provider) {
   // called when the GPS provider is turned on (user turning on the GPS on the phone)
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {

}

and in my MainActivity

            LocationListener locationListener = new MyLocationListener();
        LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);

        lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListener);

Now, all I want is to receive the current position of the device ONCE to the MainActivity class (get altitude and longitude variables to use later in the application).

A. how do I stop receiving the location after a single time? The function lm.removeUpdates(listener) can only be called in the MainActivity class.

B. basically the same. How do I connect between the MyLocationListener class and the MainActivity one?

Sorry, I'm a newbie to Android and Java development. And thanks!


Solution

  • You may use the following sample code:

    public class LocationGetter {
        private final Context context;
        private Location location = null;
        private final Cordinate gotLocationLock = new Cordinate();
        private final LocationResult locationResult = new LocationResult() {
            @Override
            public void gotLocation(Location location) {
                synchronized (gotLocationLock) {
                    LocationGetter.this.location = location;
                    gotLocationLock.notifyAll();
                    Looper.myLooper().quit();
                }
            }
        };
    
        public LocationGetter(Context context) {
            if (context == null)
                throw new IllegalArgumentException("context == null");
    
            this.context = context;
        }
    
        public  void getLocation(int maxWaitingTime, int updateTimeout) {
            try {
                final int updateTimeoutPar = updateTimeout;
                synchronized (gotLocationLock) {
                    new Thread() {
                        public void run() {
                            Looper.prepare();
                            LocationResolver locationResolver = new LocationResolver();
                            locationResolver.prepare();
                            locationResolver.getLocation(context, locationResult, updateTimeoutPar);
                            Looper.loop();
                        }
                    }.start();
    
                    gotLocationLock.wait(maxWaitingTime);
                }
            } catch (InterruptedException e1) {
                e1.printStackTrace();
            }
            gteAddress ();
        }
    
    
    public double getLatitude() {
        return location.getLatitude();
    }
    
    public double getLongitude() {
        return location.getLongitude();
    }
    

    In your activity use:

    _locationGetter=new LocationGetter(context);
    
    _locationGetter.getLocation(200000000, 10000000);
    
    _locationGetter.getLongitude();
    
    _locationGetter.getLatitude();