LocationServices.java

/*
 * Copyright (C) 2014 The Context Engine Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package uk.ac.tvu.mdse.contextengine;

import java.util.ArrayList;

import uk.ac.tvu.mdse.contextengine.contexts.LocationContextTest;
import android.content.Context;
import android.content.Intent;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.provider.Settings;
import android.util.Log;

public class LocationServices implements LocationListener {

	private LocationManager locationManager;
	private String provider;
	private Location location;

	public static final String LOG_TAG = "LocationServices";
	public static final boolean D = true;

	Context context;

	// in real life you *DO NOT* want to do this, it may consume too many
	// resources
	// (time less than 60000ms for minTime is NOT recommended, used only for
	// testing)
	private int minTime = 3000; // in milliseconds
	private int minDistance = 1000; // in meters

	private ArrayList<LocationContextTest> locationContexts = new ArrayList<LocationContextTest>();

	public LocationServices(Context c) {
		if (D)
			Log.d(LOG_TAG, "constructor");
		this.context = c;

		locationManager = (LocationManager) c
				.getSystemService(Context.LOCATION_SERVICE);

		Criteria criteria = new Criteria();
		criteria.setAccuracy(Criteria.ACCURACY_COARSE);
		criteria.setAltitudeRequired(false);
		criteria.setBearingRequired(false);
		criteria.setCostAllowed(true);
		criteria.setPowerRequirement(Criteria.NO_REQUIREMENT);

		provider = locationManager.getBestProvider(criteria, false);
		Log.v("LocationServices", "LocationServices3 " + provider.toString());

		if (provider != null && locationManager.isProviderEnabled(provider)) {
			// set minTime(milliseconds) and minDistance(meters)
			locationManager.requestLocationUpdates(provider, minTime,
					minDistance, this);

			location = locationManager.getLastKnownLocation(provider);
			Log.v("constr-LocationServices",
					"Latitude= " + location.getLatitude() + " Longitude= "
							+ location.getLongitude());
			Log.v("LocationServices",
					"Location accuracy: " + location.getAccuracy());
		} else {
			Intent myIntent = new Intent(
					Settings.ACTION_LOCATION_SOURCE_SETTINGS);
			c.startActivity(myIntent);
		}
	}

	public void setUpdatesCriteria(int time, int distance) {
		if (D)
			Log.d(LOG_TAG, "setUpdatesCriteria");
		if ((time < minTime) || (distance < minDistance)) {
			this.minTime = time;
			this.minDistance = distance;
			locationManager.removeUpdates(this);
			locationManager.requestLocationUpdates(provider, minTime,
					minDistance, this);
		}
	}

	public void addLocationContext(LocationContextTest locationContext) {
		if (D)
			Log.d(LOG_TAG, "addLocationContext");
		locationContexts.add(locationContext);
	}

	public Location getLocation() {
		if (D)
			Log.d(LOG_TAG, "getLocation");
		return location;
	}

	public void onLocationChanged(Location locale) {
		if (D)
			Log.d(LOG_TAG, "onLocationChanged");
		for (LocationContextTest locationContext : locationContexts) {
			locationContext.onLocationChanged(locale);
		}
		this.location = locale;
	}

	public void onProviderDisabled(String prv) {
		if (D)
			Log.v(LOG_TAG, "Provider " + prv + " disabled");

		// if best provider disabled, make GPS default
		provider = locationManager.GPS_PROVIDER;

		// check if GPS enabled, if not - ask for it
		if (!locationManager.isProviderEnabled(provider)) {
			Intent gpsOptionsIntent = new Intent(
					android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS);
			context.startActivity(gpsOptionsIntent);
		}
	}

	public void onProviderEnabled(String prv) {
		if (D)
			Log.v(LOG_TAG, "Provider " + prv + " enabled");
		locationManager.removeUpdates(this);
		locationManager.requestLocationUpdates(provider, minTime, minDistance,
				this);

		location = locationManager.getLastKnownLocation(provider);
		if (D)
			Log.v(LOG_TAG, "Latitude= " + location.getLatitude()
					+ " Longitude= " + location.getLongitude());
		if (D)
			Log.v(LOG_TAG, "Location accuracy: " + location.getAccuracy());
	}

	public void onStatusChanged(String prv, int stat, Bundle extras) {
		if (stat == 2) {
			locationManager.removeUpdates(this);
			locationManager.requestLocationUpdates(provider, minTime,
					minDistance, this);

			location = locationManager.getLastKnownLocation(provider);
			if (D)
				Log.v(LOG_TAG, "Latitude= " + location.getLatitude()
						+ " Longitude= " + location.getLongitude());
			if (D)
				Log.v(LOG_TAG, "Location accuracy: " + location.getAccuracy());
		}
	}

	public void stop() {
		locationManager.removeUpdates(this);
		if (D)
			Log.v(LOG_TAG, "Stopping");
	}
}