cordova-android/framework/src/com/phonegap/GeoBroker.java

/*
 * PhoneGap is available under *either* the terms of the modified BSD license *or* the
 * MIT License (2008). See http://opensource.org/licenses/alphabetical for full text.
 * 
 * Copyright (c) 2005-2010, Nitobi Software Inc.
 * Copyright (c) 2010, IBM Corporation
 */
package com.phonegap;

import java.util.HashMap;
import java.util.Map.Entry;

import org.json.JSONArray;
import org.json.JSONException;

import com.phonegap.api.Plugin;
import com.phonegap.api.PluginResult;

/*
 * This class is the interface to the Geolocation.  It's bound to the geo object.
 * 
 * This class only starts and stops various GeoListeners, which consist of a GPS and a Network Listener
 */

public class GeoBroker extends Plugin {
    
    // List of gGeolocation listeners
    private HashMap<String, GeoListener> geoListeners;
	private GeoListener global;
	
	/**
	 * Constructor.
	 */
	public GeoBroker() {
		this.geoListeners = new HashMap<String, GeoListener>();
	}

	/**
	 * Executes the request and returns PluginResult.
	 * 
	 * @param action 		The action to execute.
	 * @param args 			JSONArry of arguments for the plugin.
	 * @param callbackId	The callback id used when calling back into JavaScript.
	 * @return 				A PluginResult object with a status and message.
	 */
	public PluginResult execute(String action, JSONArray args, String callbackId) {
		PluginResult.Status status = PluginResult.Status.OK;
		String result = "";		
		
		try {
			if (action.equals("getCurrentLocation")) {
				this.getCurrentLocation(args.getBoolean(0), args.getInt(1), args.getInt(2));
			}
			else if (action.equals("start")) {
				String s = this.start(args.getString(0), args.getBoolean(1), args.getInt(2), args.getInt(3));
				return new PluginResult(status, s);
			}
			else if (action.equals("stop")) {
				this.stop(args.getString(0));
			}
			return new PluginResult(status, result);
		} catch (JSONException e) {
			return new PluginResult(PluginResult.Status.JSON_EXCEPTION);
		}
	}

	/**
	 * Identifies if action to be executed returns a value and should be run synchronously.
	 * 
	 * @param action	The action to execute
	 * @return			T=returns value
	 */
	public boolean isSynch(String action) {
		// Starting listeners is easier to run on main thread, so don't run async.
		return true;
	}
    
    /**
     * Called when the activity is to be shut down.
     * Stop listener.
     */
    public void onDestroy() {
		java.util.Set<Entry<String,GeoListener>> s = this.geoListeners.entrySet();
        java.util.Iterator<Entry<String,GeoListener>> it = s.iterator();
        while (it.hasNext()) {
            Entry<String,GeoListener> entry = it.next();
            GeoListener listener = entry.getValue();
            listener.destroy();
		}
        this.geoListeners.clear();
        if (this.global != null) {
        	this.global.destroy();
        }
        this.global = null;
    }

    //--------------------------------------------------------------------------
    // LOCAL METHODS
    //--------------------------------------------------------------------------

    /**
     * Get current location.
     * The result is returned to JavaScript via a callback.
     * 
	 * @param enableHighAccuracy
	 * @param timeout
	 * @param maximumAge
     */
	public void getCurrentLocation(boolean enableHighAccuracy, int timeout, int maximumAge) {
		
		// Create a geolocation listener just for getCurrentLocation and call it "global"
		if (this.global == null) {
			this.global = new GeoListener(this, "global", maximumAge);
		}
		else {
			this.global.start(maximumAge);
		}
	}
	
	/**
	 * Start geolocation listener and add to listener list.
	 * 
	 * @param key					The listener id
	 * @param enableHighAccuracy
	 * @param timeout
	 * @param maximumAge
	 * @return
	 */
	public String start(String key, boolean enableHighAccuracy, int timeout, int maximumAge) {
		
		// Make sure this listener doesn't already exist
		GeoListener listener = geoListeners.get(key);
		if (listener == null) {
			listener = new GeoListener(this, key, maximumAge);
			geoListeners.put(key, listener);
		}
		
		// Start it
		listener.start(maximumAge);
		return key;
	}
	
	/**
	 * Stop geolocation listener and remove from listener list.
	 * 
	 * @param key			The listener id
	 */
	public void stop(String key) {
		GeoListener listener = geoListeners.remove(key);
		if (listener != null) {
			listener.stop();
		}
	}
}