Auf dieser Seite zeigen wir, wie man unter Android auf das GPS zugreifen kann und mit den Daten arbeitet. Die App prüft, ob die Berechtigungen für die Ortungsdienste gegeben sind. Wenn ja, so wird die Position bestimmt. Wird der Refresh-Button betätigt, so wird "onLocationChanged" aufgerufen. Diese Funktion wird übrigens auch automatisch aufgerufen, wenn Android merkt, dass sich die Position ändert. Die App versucht auch, den Namen der Ortschaft, in der man sich zurzeit befindet zu ermitteln.

Verfügbare Parameter

• Latitude (Geographische Breite)
• Longitude (Geographische Länge)
• Locality (Name der Ortschaft)
• Speed (Geschwindigkeit in m/s)
• Altitude (Seehöhe in Meter)
• Satellites (Anzahl der Satelliten)

Zuerst muss in der Manifest die Berechtigung für den GPS-Zugriff definiert werden:

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

Anschließend wird der Code in die MainActivity kopiert:

package aeqweb.com.gpsinfo;

import java.io.IOException;
import java.util.Calendar;
import java.util.List;
import java.util.Locale;
import android.app.Activity;
import android.content.Context;
import android.content.pm.ActivityInfo;
import android.content.pm.PackageManager;
import android.graphics.Color;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.support.v4.content.ContextCompat;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends Activity
        implements OnClickListener {

    private LocationManager locationMangaer = null;
    private LocationListener locationListener = null;
    private Button btnGetLocation = null;
    private TextView v_longitude = null;
    private TextView v_latitude = null;
    private TextView v_location = null;
    private TextView v_speed = null;
    private TextView v_altitude = null;
    private TextView v_sat = null;
    private TextView v_gps_status = null;
    private TextView v_update_status = null;
    String longitude = "";
    String latitude = "";
    String location = "";
    String speed = "";
    String altitude = "";
    String sat_nr = "";

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT); //portrait mode
        v_longitude = (TextView) findViewById(R.id.Lon_view);
        v_latitude = (TextView) findViewById(R.id.Lat_view);
        v_location = (TextView) findViewById(R.id.Loc_view);
        v_speed = (TextView) findViewById(R.id.Spd_view);
        v_altitude = (TextView) findViewById(R.id.Alt_view);
        v_sat = (TextView) findViewById(R.id.Sat_view);
        v_gps_status = (TextView) findViewById(R.id.Gps_status);
        v_update_status = (TextView) findViewById(R.id.Update_status);

        btnGetLocation = (Button) findViewById(R.id.button);
        btnGetLocation.setOnClickListener(this);
        locationMangaer = (LocationManager)
                getSystemService(Context.LOCATION_SERVICE);
    }

    @Override
    public void onClick(View v) {
        //Check if GPS is enabled
        locationListener = new APPLocationListener();
        if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) ==
                PackageManager.PERMISSION_GRANTED) {
            v_gps_status.setText("Wait for signal");
            v_gps_status.setTextColor(Color.parseColor("#0066ff"));
            locationMangaer.requestLocationUpdates(LocationManager
                    .GPS_PROVIDER, 5000, 10, locationListener);
        } else {
            v_gps_status.setText("No GPS-Access!!!");
            v_gps_status.setTextColor(Color.parseColor("#ff0000"));
        }
    }

    private class APPLocationListener implements LocationListener {
        @Override
        public void onLocationChanged(Location loc) {
            //Try to get city name
            String city_name = null;
            Geocoder gcd = new Geocoder(getBaseContext(),
                    Locale.getDefault());
            List
 addresses;
            try {
                addresses = gcd.getFromLocation(loc.getLatitude(), loc
                        .getLongitude(), 1);
                if (addresses.size() > 0)
                    city_name = addresses.get(0).getLocality();
            } catch (IOException e) {
                city_name = "unknown";
                e.printStackTrace();
            }
            latitude = "" + loc.getLatitude(); //Get latitude
            longitude = "" + loc.getLongitude(); //Get longitude
            location = "" + city_name; //Get city name
            speed = "" + loc.getSpeed() + " m/s"; //Get speed in meters per second
            altitude = "" + loc.getAltitude() + " m"; //Get height in meters
            sat_nr = "" + loc.getExtras().getInt("satellites"); //available satellites
            v_latitude.setText(latitude);
            v_longitude.setText(longitude);
            v_location.setText(location);
            v_speed.setText(speed);
            v_altitude.setText(altitude);
            v_sat.setText(sat_nr);
            v_gps_status.setText("GPS working");
            v_gps_status.setTextColor(Color.parseColor("#33cc33"));
            Calendar c = Calendar.getInstance(); //Get time on system
            v_update_status.setText("Last update: " + c.get(Calendar.HOUR_OF_DAY) + ":" +
                    c.get(Calendar.MINUTE) + ":" + c.get(Calendar.SECOND));
        }
        @Override
        public void onProviderDisabled(String provider) {
            // TODO Auto-generated method stub
        }
        @Override
        public void onProviderEnabled(String provider) {
            // TODO Auto-generated method stub
        }
        @Override
        public void onStatusChanged(String provider,
                                    int status, Bundle extras) {
            // TODO Auto-generated method stub
        }
    }
}