位置跟踪服务会降低应用速度

Question

for a project I needed an app that opens a webpage in a webview and at the same time tracks the users location, even if the phone is not active or another app is in front.

I got this working and everything works as it should. The location is retrieved and the server is able to work with the locations.

The problem is, that if I switch back into the app after more than two hours of background tracking, everything is slowed down and the response time in the webview is very bad.

It seems as if the location service is slowing down the app. Before the service was installed this problem did not exist. I cant explain, what causes the app to lack, maybe somebody can help me.

This is the code of my location service. It gets called as an Intent in the onCreate of the Webview. The Locations gets written in a string buffer that gets uploaded to a server. (Some empty override functions are left out)

public class MyLocationService extends Service {

    double latService;
    double lngService;
    long timeService;
    float accService;
    long oldtime;
    String hash = "";
    String buffer = "";
    private LocationManager lm;

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        final Handler handler = new Handler();
        final Runnable r = new Runnable() {
            public void run() {
                LocationUpdates();
                if ((timeService > 0) && (oldtime != timeService)) {
                    oldtime = timeService;
                    if (buffer.equals("")) {
                        buffer += latService + "," + lngService + "," + accService + "," + timeService;
                    } else {
                        buffer += ";" + latService + "," + lngService + "," + accService + "," + timeService;
                    }
                    AsyncHttpClient client = new AsyncHttpClient();
                    RequestParams params = new RequestParams();
                    params.put("d", buffer);
                    client.post("server.php", params, new TextHttpResponseHandler() {
                        @Override
                        public void onSuccess(int arg0, Header[] arg1, String arg2) {
                            System.out.println(arg2);
                            buffer = "";
                        }
                    });
                }
                handler.postDelayed(this, 15000);
            }
        };
        handler.postDelayed(r, 10);
        return Service.START_NOT_STICKY;
    }

    public void LocationUpdates() {
        locListener locList = new locListener();
        lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locList);
    }

    public class locListener implements LocationListener {
        @Override
        public void onLocationChanged(Location location) {
            latService = location.getLatitude();
            lngService = location.getLongitude();
            timeService = Math.round(location.getTime() / 1000);
            accService = location.getAccuracy();
        }
    }
}

Thanks in advance for any help.

Answer 1

I would highly recommend using the Fused location provider with PRIORITY_BALANCED_POWER_ACCURACY:

LocationRequest request = LocationRequest.create()
        .setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY)
        .setInterval(POLLING_INTERVAL)
        .setFastestInterval(POLLING_INTERVAL/2)
        .setSmallestDisplacement(MIN_INTERVAL_METERS);

It is designed to provide you with a in a 40 meter range accuracy with battery consumption <= 0.6%/hour.

Also remember to turn location listening off immediately when no longer needed.