Update location on OpenStreetMap

Combine the exercises "Simple example use osmdroid and slf4j-android to implement OpenStreetMapView on Android" and "Location updates from GPS_PROVIDER and NETWORK_PROVIDER" we create a OpenStreetMap to center on user location.

By calling MapController.setCenter(GeoPoint), we can move OpenStreetMap to center on a certain location.

Modify AndroidOpenStreetMapViewActivity.java to implement LocationListener, and updateLoc(Location) method to update and redraw OpenStreetMap once location changed.

package com.exercise.OpenStreetMapView;

import org.osmdroid.util.GeoPoint;
import org.osmdroid.views.MapController;
import org.osmdroid.views.MapView;

import android.app.Activity;
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;

public class AndroidOpenStreetMapViewActivity extends Activity {
 
 private MapView myOpenMapView;
 private MapController myMapController;
 
 LocationManager locationManager;
 
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        myOpenMapView = (MapView)findViewById(R.id.openmapview);
        myOpenMapView.setBuiltInZoomControls(true);
        myMapController = myOpenMapView.getController();
        myMapController.setZoom(12);
        
        locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
        
        //for demo, getLastKnownLocation from GPS only, not from NETWORK
        Location lastLocation = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
        if(lastLocation != null){
         updateLoc(lastLocation);
        }
        
    }
    
    @Override
 protected void onResume() {
  // TODO Auto-generated method stub
  super.onResume();
  locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, myLocationListener);
  locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, myLocationListener);
 }

 @Override
 protected void onPause() {
  // TODO Auto-generated method stub
  super.onPause();
  locationManager.removeUpdates(myLocationListener);
 }

 private void updateLoc(Location loc){
     GeoPoint locGeoPoint = new GeoPoint(loc.getLatitude(), loc.getLongitude());
     myMapController.setCenter(locGeoPoint);
     myOpenMapView.invalidate();
    }
    
    private LocationListener myLocationListener
    = new LocationListener(){

  @Override
  public void onLocationChanged(Location location) {
   // TODO Auto-generated method stub
   updateLoc(location);
  }

  @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
   
  }
     
    };

}

Keep using the main.xml in the exercises "Simple example use osmdroid and slf4j-android to implement OpenStreetMapView on Android".

Permission need:

• android.permission.ACCESS_NETWORK_STATE
• android.permission.INTERNET
• android.permission.WRITE_EXTERNAL_STORAGE
• android.permission.ACCESS_FINE_LOCATION

Download the files.

Next:
- Add Scale Bar on OpenStreetMap