How to periodically find gps location in Android

Question

I am writing an app that records a new gps location every ten minutes on the dot.

I've tried location pollers, putting the location listener in a service, and putting the location listener in an activity but none of these methods work for me.

I need a method to turn on the gps location listener 2 minutes before I begin recording my location data (to give the gps ample time to find a location or determine there is no signal). I've been doing this by using an alarm that calls my gpsActivity 2 minutes before I call my updatelocation class. My updatelocation class then takes the gpsActivity's locationmanager and extracts a location from it.

In theory this should work but when I put it on my phone I always get bad data (accuracy is too low or no signal at all)

If someone could help me out I would be extremely grateful.

Thanks

Alarm calls this class 2 mins before update location

public class GPSActivity extends Activity {

    public static LocationListener loc_listener = null;
    public static LocationManager locationManager = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
        getGPS();
    }

    public static void getGPS() {
        if (loc_listener == null) {
            loc_listener = new LocationListener() {

                @Override
                public void onStatusChanged(String provider, int status,
                        Bundle extras) {}

                @Override
                public void onProviderEnabled(String provider) {}

                @Override
                public void onProviderDisabled(String provider) {}

                @Override
                public void onLocationChanged(Location location) {}
            };
        }
        locationManager.requestLocationUpdates(
                LocationManager.GPS_PROVIDER, 0, 0, loc_listener);
    }

    public static void killGPS() {
        if (locationManager != null && loc_listener != null) {
            locationManager.removeUpdates(loc_listener);
        }
    }
}

then two mins later this service is called

public class UpdateLocation extends IntentService {

    public static final String id = "";
    public static int retryCount = 0;
    int notificationID = 1;
    // gets the location manager from the GPSActivity
    LocationManager locationManager = GPSActivity.locationManager;

    @Override
    public void onDestroy() {
        super.onDestroy();
    }

    public UpdateLocation() {
        super("UpdateLocation");
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        locationManager = GPSActivity.locationManager;
        SharedPreferences prefs = getSharedPreferences("Settings", 0);
        final String id = prefs.getString("ID", "");
        HttpParams httpParams = new BasicHttpParams();
        // 30seconds and it stops
        HttpConnectionParams.setConnectionTimeout(httpParams, 30000);
        HttpConnectionParams.setSoTimeout(httpParams, 30000);
        DefaultHttpClient httpclient = new DefaultHttpClient(httpParams);
        HttpPost httpost = new HttpPost(
                "http://iphone-radar.com/gps/gps_locations");
        JSONObject holder = new JSONObject();
        try {
            holder.put("id", id);
            Location location = getLocation();
            if (location != null && (location.getAccuracy() < 25)) {
                retryCount = 0;
                Calendar c = Calendar.getInstance();
                SimpleDateFormat sdf = new SimpleDateFormat(
                        "hh:mmaa MM/dd/yyyy");
                holder.put("time", sdf.format(c.getTime()));
                holder.put("time_since_epoch",
                        System.currentTimeMillis() / 1000);
                holder.put("lat", location.getLatitude());
                holder.put("lon", location.getLongitude());
                StringEntity se = new StringEntity(holder.toString());
                httpost.setEntity(se);
                httpost.setHeader("Accept", "application/json");
                httpost.setHeader("Content-type", "application/json");
                ResponseHandler responseHandler = new BasicResponseHandler();
                String response = httpclient.execute(httpost,
                        responseHandler);
                org.json.JSONObject obj;
                obj = new org.json.JSONObject(response);
                SimpleDateFormat sdf2 = new SimpleDateFormat(
                        "yyyy-MM-dd hh:mm:ssaa");
                addHistory(
                        sdf2.format(c.getTime()),
                        "Background GPS",
                        "Latitude: "
                            + String.format("%.6g%n",
                                    location.getLatitude())
                            + "\n"
                            + "Longitude: "
                            + String.format("%.6g%n",
                                    location.getLongitude()));
                SharedPreferences.Editor editor = prefs.edit();
                editor.putString("LastUpdatedTime", sdf.format(c.getTime()));
                editor.commit();
                Intent setAlarm = new Intent(UpdateLocation.this,
                        UpdateLocation.class);
                PendingIntent pendingIntent = PendingIntent.getService(
                        UpdateLocation.this, 0, setAlarm, 0);
                AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
                Calendar calendar = Calendar.getInstance();
                calendar.setTimeInMillis(System.currentTimeMillis());
                int UPDATE_TIME = prefs.getInt("Update_time", 10);
                calendar.add(Calendar.MINUTE, UPDATE_TIME);
                alarmManager.set(AlarmManager.RTC_WAKEUP,
                        calendar.getTimeInMillis(), pendingIntent);
                // sets an alarm for the next time we need to record a
                // location
                GPSActivity.killGPS();
                // turns off the gps location listener
                Intent setAlarm2 = new Intent(UpdateLocation.this,
                        GPSActivity.class);
                PendingIntent pendingIntent2 = PendingIntent.getService(
                        UpdateLocation.this, 0, setAlarm2, 0);
                Calendar calendar2 = Calendar.getInstance();
                calendar2.add(Calendar.MINUTE, UPDATE_TIME - 2);
                alarmManager.set(AlarmManager.RTC_WAKEUP,
                        calendar2.getTimeInMillis(), pendingIntent2);
                // sets an alarm to turn on the gpsActivity 2mins before the
                // next time updatelocation needs to record some data
            }
        } finally {
        }
    }
}

Answer 1

Use receiver and service together. For this purpose you can find a complete sample in this link. There is a listener in it. Listener can be used in your activity to be noticed that a new location is ready for you.