Current position on google maps

Question

i would like to show my current position on an android phone using google maps. Would the code below be able to show my current pos on google maps?

MapsActivity.java

package log1.log2;

import log1.log2.MyLocation.LocationResult;

import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapController;
import com.google.android.maps.MapView;
import com.google.android.maps.MapView.LayoutParams;

import android.location.Criteria;
import android.location.Location;
import android.location.LocationManager;
import android.os.Bundle;
import android.view.View;
import android.widget.LinearLayout;

public class MapsActivity extends MapActivity 
{    
    MapView mapView; 
    MapController mc;
    GeoPoint p;

    /** Called when the activity is first created. */
    @SuppressWarnings("deprecation")
    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.mapactivity);

        mapView = (MapView) findViewById(R.id.mapView);
        LinearLayout zoomLayout = (LinearLayout)findViewById(R.id.zoom);  
        View zoomView = mapView.getZoomControls(); 
        zoomLayout.addView(zoomView, 
            new LinearLayout.LayoutParams(
                LayoutParams.WRAP_CONTENT, 
                LayoutParams.WRAP_CONTENT)); 
        mapView.displayZoomControls(true);
    }
    MyLocation myLocation = new MyLocation();
    private void locationClick() {
        myLocation.getLocation(this, locationResult);
    }

    public LocationResult locationResult = new LocationResult(){
        public void gotLocation(final Location location){
            //Got the location!
            };
        };

    @Override
    protected boolean isRouteDisplayed() {
        // TODO Auto-generated method stub
        return false;
    }
}

MyLocation.java

package log1.log2;

import java.util.Timer;
import java.util.TimerTask;
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;

public class MyLocation {
    Timer timer1;
    LocationManager lm;
    LocationResult locationResult;
    boolean gps_enabled=false;
    boolean network_enabled=false;

    public boolean getLocation(Context context, LocationResult result)
    {
        //I use LocationResult callback class to pass location value from MyLocation to user code.
        locationResult=result;
        if(lm==null)
            lm = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);

        //exceptions will be thrown if provider is not permitted.
        try{gps_enabled=lm.isProviderEnabled(LocationManager.GPS_PROVIDER);}catch(Exception ex){}
        try{network_enabled=lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);}catch(Exception ex){}

        //don't start listeners if no provider is enabled
        if(!gps_enabled && !network_enabled)
            return false;

        if(gps_enabled)
            lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps);
        if(network_enabled)
            lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListenerNetwork);
        timer1=new Timer();
        timer1.schedule(new GetLastLocation(), 20000);
        return true;
    }

    LocationListener locationListenerGps = new LocationListener() {
        public void onLocationChanged(Location location) {
            timer1.cancel();
            locationResult.gotLocation(location);
            lm.removeUpdates(this);
            lm.removeUpdates(locationListenerNetwork);
        }
        public void onProviderDisabled(String provider) {}
        public void onProviderEnabled(String provider) {}
        public void onStatusChanged(String provider, int status, Bundle extras) {}
    };

    LocationListener locationListenerNetwork = new LocationListener() {
        public void onLocationChanged(Location location) {
            timer1.cancel();
            locationResult.gotLocation(location);
            lm.removeUpdates(this);
            lm.removeUpdates(locationListenerGps);
        }
        public void onProviderDisabled(String provider) {}
        public void onProviderEnabled(String provider) {}
        public void onStatusChanged(String provider, int status, Bundle extras) {}
    };

    class GetLastLocation extends TimerTask {
        @Override
        public void run() {
             lm.removeUpdates(locationListenerGps);
             lm.removeUpdates(locationListenerNetwork);

             Location net_loc=null, gps_loc=null;
             if(gps_enabled)
                 gps_loc=lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
             if(network_enabled)
                 net_loc=lm.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);

             //if there are both values use the latest one
             if(gps_loc!=null && net_loc!=null){
                 if(gps_loc.getTime()>net_loc.getTime())
                     locationResult.gotLocation(gps_loc);
                 else
                     locationResult.gotLocation(net_loc);
                 return;
             }

             if(gps_loc!=null){
                 locationResult.gotLocation(gps_loc);
                 return;
             }
             if(net_loc!=null){
                 locationResult.gotLocation(net_loc);
                 return;
             }
             locationResult.gotLocation(null);
        }
    }

    public static abstract class LocationResult{
        public abstract void gotLocation(Location location);
    }
}

Thank you.

Solution 1

If you only want to show your own location, than a MyLocationOverlay is probably easiest.

Quick information here (rest of that article might be helpful too):

http://www.vogella.com/articles/AndroidLocationAPI/article.html#maps_mylocation

About not being able to test it in the emulator: You can test it. In Eclipse switch to DDMS Perspective and in the left you see "Emulator Control" there you can "Send" Locations below "Location Controls". This is as well described in the above tutorial.

Solution 2

Don't know i havent gone through the code but following code works for me:

public class GoogleMapsActivity extends MapActivity {
    public static final String TAG = "GoogleMapsActivity";
    private MapView mapView;
    private LocationManager locationManager;
    Geocoder geocoder;
    Location location;
    LocationListener locationListener;
    CountDownTimer locationtimer;
    MapController mapController;
    MapOverlay mapOverlay = new MapOverlay();

    @Override
    protected void onCreate(Bundle icicle) {
        super.onCreate(icicle);
        setContentView(R.layout.googlemap);
        initComponents();
        mapView.setBuiltInZoomControls(true);
        mapView.setSatellite(true);
        mapController = mapView.getController();
        mapController.setZoom(16);
        locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
        if (locationManager == null) {
            Toast.makeText(GoogleMapsActivity.this,
                    "Location Manager Not Available", Toast.LENGTH_SHORT)
                    .show();
            return;
        }
        location = locationManager
                .getLastKnownLocation(LocationManager.GPS_PROVIDER);
        if (location == null)
            location = locationManager
                    .getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
        if (location != null) {
            double lat = location.getLatitude();
            double lng = location.getLongitude();
            Toast.makeText(GoogleMapsActivity.this,
                    "Location Are" + lat + ":" + lng, Toast.LENGTH_SHORT)
                    .show();
            GeoPoint point = new GeoPoint((int) (lat * 1E6), (int) (lng * 1E6));
            mapController.animateTo(point, new Message());
            mapOverlay.setPointToDraw(point);
            List<Overlay> listOfOverlays = mapView.getOverlays();
            listOfOverlays.clear();
            listOfOverlays.add(mapOverlay);
        }
        locationListener = new LocationListener() {
            @Override
            public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
            }

            @Override
            public void onProviderEnabled(String arg0) {
            }

            @Override
            public void onProviderDisabled(String arg0) {
            }

            @Override
            public void onLocationChanged(Location l) {
                location = l;
                locationManager.removeUpdates(this);
                if (l.getLatitude() == 0 || l.getLongitude() == 0) {
                } else {
                    double lat = l.getLatitude();
                    double lng = l.getLongitude();
                    Toast.makeText(GoogleMapsActivity.this,
                            "Location Are" + lat + ":" + lng,
                            Toast.LENGTH_SHORT).show();
                }
            }
        };
        if (locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER))
            locationManager.requestLocationUpdates(
                    LocationManager.GPS_PROVIDER, 1000, 10f, locationListener);
        locationManager.requestLocationUpdates(
                LocationManager.NETWORK_PROVIDER, 1000, 10f, locationListener);
        locationtimer = new CountDownTimer(30000, 5000) {
            @Override
            public void onTick(long millisUntilFinished) {
                if (location != null)
                    locationtimer.cancel();
            }

            @Override
            public void onFinish() {
                if (location == null) {
                }
            }
        };
        locationtimer.start();
    }

    public MapView getMapView() {
        return this.mapView;
    }

    private void initComponents() {
        mapView = (MapView) findViewById(R.id.googleMapview);
    }

    @Override
    protected boolean isRouteDisplayed() {
        return false;
    }

    class MapOverlay extends Overlay {
        private GeoPoint pointToDraw;

        public void setPointToDraw(GeoPoint point) {
            pointToDraw = point;
        }

        public GeoPoint getPointToDraw() {
            return pointToDraw;
        }

        @Override
        public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
                long when) {
            super.draw(canvas, mapView, shadow);

            Point screenPts = new Point();
            mapView.getProjection().toPixels(pointToDraw, screenPts);

            Bitmap bmp = BitmapFactory.decodeResource(getResources(),
                    R.drawable.pingreen);
            canvas.drawBitmap(bmp, screenPts.x, screenPts.y - 24, null);
            return true;
        }
    }

}