Am I using alarms properly?

I have an android app that will record data every x mins. The time the alarm goes off is based on the settings page (either 10 or 30 mins). The alarm is first activated when it goes into the splash screen. My problem is, it doesnt seem to be called when I'm using it on my phone and so I was hoping someone could tell me if I'm using the function properly.

    if (prefs.getBoolean("backgroundupdates", true)) {
        Intent setAlarm = new Intent(Splash.this,
                UpdateLocation.class);
        PendingIntent pendingIntent = PendingIntent.getService(
                Splash.this, 0, setAlarm, 0);
        AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
        Calendar calendar = Calendar.getInstance();
        SimpleDateFormat sdf = new SimpleDateFormat(
                "yyyy-MM-dd hh:mm:ssaa");
        History.addHistory(sdf.format(calendar.getTime()), "App Started", "");
        calendar.setTimeInMillis(System.currentTimeMillis());

        int UPDATE_TIME = prefs.getInt("Update_time", 30);
        calendar.add(Calendar.MINUTE, UPDATE_TIME);
        alarmManager.set(AlarmManager.RTC_WAKEUP,
                calendar.getTimeInMillis(), pendingIntent);


    }

This checks if background updates are on and sets an alarm for UPDATE_TIME mins (default 30)

in my UpdateLocation.class I have this in the bottom

    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", 30);
            calendar.add(Calendar.MINUTE, UPDATE_TIME);
            alarmManager.set(AlarmManager.RTC_WAKEUP,
                    calendar.getTimeInMillis(), pendingIntent);

This is so that the alarm will call itself again in UPDATE_TIME mins. The reason I'm doing it this way is because UPDATE_TIME may change (depending on user preferences)

Thanks!

EDIT here is my UpdateLocation.class

public class UpdateLocation extends IntentService {
    public static final String id = "";

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

    @Override
    protected void onHandleIntent(Intent intent) {

        SharedPreferences prefs = getSharedPreferences("Settings", 0);
        final String id = prefs.getString("ID", "");
        if (prefs.getBoolean("backgroundupdates", true)) {
            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);
                LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
                Criteria criteria = new Criteria();
                criteria.setAccuracy(Criteria.ACCURACY_FINE);
                String bestProvider = locationManager.getBestProvider(criteria,
                        false);
                LocationListener loc_listener = new LocationListener() {

                    @Override
                    public void onStatusChanged(String provider, int status,
                            Bundle extras) {
                        // TODO Auto-generated method stub

                    }

                    @Override
                    public voi开发者_开发百科d onProviderEnabled(String provider) {
                        // TODO Auto-generated method stub

                    }

                    @Override
                    public void onProviderDisabled(String provider) {
                        // TODO Auto-generated method stub

                    }

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

                    }
                };
                try {
                    Looper.prepare();
                    locationManager.requestLocationUpdates(bestProvider, 0, 0,
                            loc_listener);
                } catch (Exception e) {
                    e.printStackTrace();
                }
                Location location = locationManager
                        .getLastKnownLocation(bestProvider);
                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);
                try {
                    holder.put("lat", location.getLatitude());
                    holder.put("lon", location.getLongitude());
                } catch (NullPointerException e) {
                    try {
                        holder.put("lat", -1.0);
                        holder.put("lon", -1.0);
                    } catch (JSONException e1) {
                        // TODO Auto-generated catch block
                        e1.printStackTrace();
                    }
                }

                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;
                SimpleDateFormat sdf2 = new SimpleDateFormat(
                        "yyyy-MM-dd hh:mm:ssaa");
                try{
                History.addHistory(sdf2.format(c.getTime()), "GPS",
                        "Latitude: " + location.getLatitude() + "\n"
                                + "Longitude: " + location.getLongitude());}
                catch(NullPointerException e){
                    History.addHistory(sdf2.format(c.getTime()), "GPS",
                            "Latitude: " + "No Signal" + "\n"
                                    + "Longitude: " + "No Signal");
                }
                obj = new org.json.JSONObject(response);
                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", 30);
                calendar.add(Calendar.MINUTE, UPDATE_TIME);
                alarmManager.set(AlarmManager.RTC_WAKEUP,
                        calendar.getTimeInMillis(), pendingIntent);

            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (UnsupportedEncodingException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (ClientProtocolException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

        }
    }

}

Note, I do not have a broadcast receiver, I'm not quite sure how to use it so any examples would be very helpful.

Could you possibly post all of your UpdateLocation.class? It needs to extend BroadcastReceiver so that may be where your problem lies.

As for your alarm, if it's being set to go off every xx minutes without end, you're better off using alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), UPDATE_TIME * 60000, pendingIntent); to have your alarm reset on a regular basis.

Edit 1

Regarding putting the PendingIntent into a static function for easy access, it could go something like this:

public static PendingIntent getPendingIntent(int update_time) {
    Intent setAlarm = new Intent(this.getBaseContext(), UpdateLocation.class);
    PendingIntent pendingIntent = PendingIntent.getService(this.getBaseContext(),
                                                           0, setAlarm, 0)
    return pendingIntent;
}

And then you can set your alarm with alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), UPDATE_TIME * 60000, MyClass.getPendingIntent());