static readonly string TAG = "X:" + typeof (Activity1).Name;
    Location _currentLocation;
    LocationManager _locationManager;

    string _locationProvider;
    TextView _locationText;

    protected override void OnCreate(Bundle bundle)
    {
        base.OnCreate(bundle);
        SetContentView(Resource.Layout.Main);

        _locationText = FindViewById<TextView>(Resource.Id.GpsTest);

        InitializeLocationManager();

        Add700ToCoordinates();
    }

    public void OnLocationChanged(Location location)
    {

        _currentLocation = location;
        if (_currentLocation == null)
        {
            _locationText.Text = "Unable to determine your location. Try again in a short while.";
        }
        else
        {
            _locationText.Text = string.Format("{0:f6},{1:f6}", _currentLocation.Latitude, _currentLocation.Longitude);
            //das her wird ausgegeben bei button.click
        }

    } // ausgabe der koordinaten

    public void OnProviderDisabled(string provider) {}

    public void OnProviderEnabled(string provider) {}

    public void OnStatusChanged(string provider, Availability status, Bundle extras)
    {
        Log.Debug(TAG, "{0}, {1}", provider, status);
    }

    void InitializeLocationManager()
    {
        _locationManager = (LocationManager) GetSystemService(LocationService);
        Criteria criteriaForLocationService = new Criteria
                                              {
                                                  Accuracy = Accuracy.Fine
                                              };
        IList<string> acceptableLocationProviders = _locationManager.GetProviders(criteriaForLocationService, true);

        if (acceptableLocationProviders.Any())
        {
            _locationProvider = acceptableLocationProviders.First();
        }
        else
        {
            _locationProvider = string.Empty;
        }
        Log.Debug(TAG, "Using " + _locationProvider + ".");
    }

    protected override void OnResume()
    {
        base.OnResume();
        _locationManager.RequestLocationUpdates(_locationProvider, 0, 0, this);
        Log.Debug(TAG, "Listening for location updates using " + _locationProvider + ".");
    }

    protected override void OnPause()
    {
        base.OnPause();
        _locationManager.RemoveUpdates(this);
        Log.Debug(TAG, "No longer listening for location updates.");
    }

    public string StringWithLocation(Location location)
    {
        string StringWithCoordinates = "Null";

        _currentLocation = location;
        if (_currentLocation == null)
        {
            StringWithCoordinates = "Unable to determine your location. Try again in a short while.";
        }
        else
        {
            StringWithCoordinates = string.Format("{0:f6},{1:f6}", _currentLocation.Latitude, _currentLocation.Longitude);
        }

        return StringWithCoordinates;

    }

    public void Add700ToCoordinates()
    {
       // StringWithLocation();
    }

}