see_you/GeoNavigator.java

package org.thinkname.ap.main;

import jade.util.Logger;

import java.io.FileNotFoundException;
import java.util.Map;

import org.thinkname.ap.contact.Contact;
import org.thinkname.ap.contact.ContactListChanges;
import org.thinkname.ap.contact.ContactLocation;
import org.thinkname.ap.contact.ContactManager;
import org.thinkname.ap.msn.MsnEvent;
import org.thinkname.ap.msn.MsnEventMgr;

import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;

/**
 * Handles the operations of starting/stopping My Contact location update by location provider. It also allows specifying 
 * a custom location provider to be used. 
 * <p>
 * Location update is issued by the LocationManager 
 */
public class GeoNavigator {

	/** 
	 * Custom action used for the location update Intent that is fired 
	 */
	public static final String LOCATION_UPDATE_ACTION= "com.tilab.msn.LOCATION_UPDATE";
	
	/** 
	 * Minimum distance in meters for sending new location update
	 */
	private final float MINIMUM_DISTANCECHANGE_FOR_UPDATE = 0.0f;  
    
    /** 
     * Minimum time in milliseconds for between location updates
     */
    private final long MINIMUM_TIME_BETWEEN_UPDATE = 0;  

    /** 
     * Instance of Jade Logger for debugging
     */
    private static final Logger myLogger = Logger.getMyLogger(GeoNavigator.class.getName());
    
  
	
	/** 
	 * The default location provider name  
	 */
	private static final String DEFAULT_PROVIDER_NAME=LocationManager.GPS_PROVIDER;
	
	/** 
	 * The name of the location provider to be used. 
	 */
	private static String locProviderName = DEFAULT_PROVIDER_NAME;
	
	
	/** 
	 * The instance of the {@link GeoNavigator} object. 
	 */
	private static GeoNavigator navigator = null;
	
	/**
	 * Current application context 
	 */
	private Context myContext;
	
	/** 
	 * Instance of the Android location manager. 
	 */
	private LocationManager manager;

	
	private LocationListener listener;
	
	/**
	 * Gets the single instance of GeoNavigator.
	 * 
	 * @param c the application context
	 * 
	 * @return single instance of GeoNavigator 
	 */
	public static GeoNavigator getInstance(Context c) {
		if (navigator == null)
			navigator = new GeoNavigator(c);
		return navigator;
	}
	
	
	/**
	 * Instantiates a new geo navigator.
	 * Uses the static instance of the provider name (if any) or otherwise defaults to DEFAULT_PROVIDER_NAME
	 * 
	 * @param c the application context
	 */
	private GeoNavigator(Context c) {
		manager = (LocationManager)c.getSystemService(Context.LOCATION_SERVICE);
		myContext = c;	
		listener = new ContactsLocationListener();
	}
	
	
	/**
	 * Request the Location manager to start firing intents with location updates
	 */
	public void startLocationUpdate(){
		myLogger.log(Logger.FINE, "Starting location update... for provider " +  locProviderName);
			
		manager.requestLocationUpdates(locProviderName, MINIMUM_TIME_BETWEEN_UPDATE, MINIMUM_DISTANCECHANGE_FOR_UPDATE,listener );

	}
	
	/**
	 * Sets the location provider name.
	 * @param provName the new location provider name
	 */
	public static void setLocationProviderName(String provName) {
		if (provName != null)
			locProviderName = provName;
	}
	
		
		
	/**
	 * Stop the firing of broadcast intents for location update.
	 */
	public void stopLocationUpdate(){
		myLogger.log(Logger.FINE, "Stopping location updates....");
		manager.removeUpdates(listener);
	}
	
	
	
	
	private class ContactsLocationListener implements LocationListener {

		
		public void onLocationChanged(Location location) {
			myLogger.log(Logger.FINE, ">>>>>>>>>>>>>>>>>>>> Location listener has received location update for location " + location );
			boolean hasMoved = ContactManager.getInstance().updateMyContactLocation(location);
			if(hasMoved){
				MsnEvent refresh = MsnEventMgr.getInstance().createEvent(MsnEvent.VIEW_REFRESH_EVENT);
				ContactListChanges changes = new ContactListChanges();
				Map<String,Contact> cMap = ContactManager.getInstance().getAllContacts();
				Map<String,ContactLocation> cLocMap = ContactManager.getInstance().getAllContactLocations();
				
				refresh.addParam(MsnEvent.VIEW_REFRESH_PARAM_LISTOFCHANGES, changes);
				refresh.addParam(MsnEvent.VIEW_REFRESH_CONTACTSMAP, cMap);
				refresh.addParam(MsnEvent.VIEW_REFRESH_PARAM_LOCATIONMAP, cLocMap);
				MsnEventMgr.getInstance().fireEvent(refresh);
			}
		}

		/* (non-Javadoc)
		 * @see android.location.LocationListener#onProviderDisabled(java.lang.String)
		 */
		public void onProviderDisabled(String provider) {
			// TODO Auto-generated method stub
			myLogger.log(Logger.FINE, "Location provider " +  provider + " disabled!");
		}

		/* (non-Javadoc)
		 * @see android.location.LocationListener#onProviderEnabled(java.lang.String)
		 */
		public void onProviderEnabled(String provider) {
			// TODO Auto-generated method stub
			myLogger.log(Logger.FINE, "Location provider " +  provider + " enabled!");
		}

		/* (non-Javadoc)
		 * @see android.location.LocationListener#onStatusChanged(java.lang.String, int, android.os.Bundle)
		 */
		public void onStatusChanged(String provider, int status, Bundle extras) {
			// TODO Auto-generated method stub
			myLogger.log(Logger.FINE, "Status of provider " +  provider + " has changed and now is " + status);
		}
		
	}
}