Android NetworkStats.Bucket data not updating

I am building an application which monitors applications network data usage over some interval.

On android 5 I had no problem with TrafficStats, although on android 8 using NetworkStats I always receive same data. I've read that bucket refreshes every 30 minutes or so, so I tried listening to youtube for about 1 hour but still same data usage ( in package com.google.android.youtube ).

So, my question, why does NetworkStats return always same data?

Here is my code:

public class DataService extends Service {
private int interval = 1000 * 5; //Time interval


private List<ApplicationInfo> infos;
private PackageManager packageManager;
private static int counter = 0;
private ArrayList<ValuesHolder> values;
private Context context;

private Handler mHandler;

public static final String DATA_INTENT_FILTER = "Transmitted data updated";

private Runnable mHandlerTask = new Runnable() {
    @Override
    public void run() {
        update();

        Intent intent = new Intent();
        intent.setAction(DATA_INTENT_FILTER);
        sendBroadcast(intent);

        mHandler.postDelayed(mHandlerTask, interval);
    }
};


@Override
public void onCreate() {
    super.onCreate();

    mHandler = new Handler();
    context = this;
    values = new ArrayList<>();
    packageManager = getPackageManager();
    infos = packageManager.getInstalledApplications(0);

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
        getNonSystemPackages();
    }

    mHandlerTask.run();

}

@RequiresApi(api = Build.VERSION_CODES.N)
private void getNonSystemPackages() {
    PackageManager pm = getPackageManager();
    List<ApplicationInfo> packages = pm.getInstalledApplications(PackageManager.GET_META_DATA);
    for (ApplicationInfo packageInfo : packages) {
        if (pm.getLaunchIntentForPackage(packageInfo.packageName) != null) {
            String currAppName = packageInfo.packageName;
            try {
                int uid = pm.getPackageUid(currAppName, 0);
                values.add(counter, new ValuesHolder(currAppName,
                        getTotalDataForMobile(uid) + getTotalDataForWifi(uid),
                        uid));
            } catch (PackageManager.NameNotFoundException e) {
                e.printStackTrace();
            }

        } else {
            //System App
        }

    }
}

private void update() {
    String saveString;
    long difference;
    long data;
    int uid;

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        try {
            for (int i = 0; i < values.size(); i++) {
                uid = values.get(i).getUid();
                if (TrafficStats.getUidTxBytes(uid) == TrafficStats.UNSUPPORTED) {
                    data = getTotalDataForMobile(uid) + getTotalDataForWifi(uid);
                    //Always same data
                    Log.i(values.get(i).getPackageName(), " data" + data);

                } else {
                    data = TrafficStats.getUidRxBytes(uid) + TrafficStats.getUidTxBytes(uid);

                }
            }
        } catch (NullPointerException e) {
            e.printStackTrace();
        }

    }
}

@RequiresApi(api = Build.VERSION_CODES.M)
private long getTotalDataForWifi(int uid) {
    NetworkStatsManager networkStatsManager = (NetworkStatsManager) getApplicationContext().getSystemService(Context.NETWORK_STATS_SERVICE);
    NetworkStats.Bucket bucket;
    long totalData = 0;

    NetworkStats networkStats = null;
    try {
        networkStats = networkStatsManager.queryDetailsForUid(
                ConnectivityManager.TYPE_WIFI,
                "",
                0,
                System.currentTimeMillis(),
                uid);
    } catch (RemoteException e) {
        return -1;
    }
    do {
        bucket = new NetworkStats.Bucket();
        networkStats.getNextBucket(bucket);
        totalData += bucket.getRxBytes() + bucket.getTxBytes();

    } while (networkStats.hasNextBucket());

    return totalData;
}

@RequiresApi(api = Build.VERSION_CODES.M)
private long getTotalDataForMobile(int uid) {
    NetworkStatsManager networkStatsManager = (NetworkStatsManager) getApplicationContext().getSystemService(Context.NETWORK_STATS_SERVICE);
    NetworkStats.Bucket bucket;
    NetworkStats networkStats = null;
    long totalData = 0;
    try {
        networkStats = networkStatsManager.queryDetailsForUid(
                ConnectivityManager.TYPE_MOBILE,
                "",
                0,
                System.currentTimeMillis(),
                uid);
    } catch (RemoteException e) {
        return -1;
    }
    do {
        bucket = new NetworkStats.Bucket();
        networkStats.getNextBucket(bucket);
        totalData += bucket.getRxBytes() + bucket.getTxBytes();

    } while (networkStats.hasNextBucket());

    return totalData;
}
}

I request runtime permissions in my MainActivity like this:

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        if (checkSelfPermission(Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(this, Permissions.ARR_PHONE_STATE, Permissions.REQUEST_PHONE_STATE);
        }

        if
                ((checkSelfPermission(Manifest.permission.ACCESS_NETWORK_STATE) != PackageManager.PERMISSION_GRANTED)
                || (checkSelfPermission(Manifest.permission.ACCESS_WIFI_STATE) != PackageManager.PERMISSION_GRANTED)
                || (checkSelfPermission(Manifest.permission.INTERNET) != PackageManager.PERMISSION_GRANTED)) {
            ActivityCompat.requestPermissions(this, Permissions.ARR_NETWORK, Permissions.REQUEST_NETWORK);
        }

        AppOpsManager appOps = (AppOpsManager) getSystemService(Context.APP_OPS_SERVICE);
        int mode = appOps.checkOpNoThrow(AppOpsManager.OPSTR_GET_USAGE_STATS,
                android.os.Process.myUid(), getPackageName());
        if (mode == AppOpsManager.MODE_ALLOWED) {
        } else {
        }
        if (!Permissions.checkForPermission(this)) {
            startActivity(new Intent(Settings.ACTION_USAGE_ACCESS_SETTINGS));
        } else {
            Log.i("SYSTEM", "PERMISSION GRANTED");
        }
    }

Permissions are granted, I request them in android manifest as well.

Thanks for any help.

Answering my own question, for someone who might have same problem. I figured out that with method queryDetailsForUid are data refreshed in quite large interval ( 3 hours or so ).

Here is solution that works well:

private long getApplicationUsage(int networkType, int uid) {
    long usage = 0L;

    NetworkStats networkStatsByApp;
    NetworkStatsManager networkStatsManager = (NetworkStatsManager) getApplicationContext().getSystemService(Context.NETWORK_STATS_SERVICE);
    try {
        networkStatsByApp = networkStatsManager.querySummary(networkType, "", 0, System.currentTimeMillis());
        do {
            NetworkStats.Bucket bucket = new NetworkStats.Bucket();
            networkStatsByApp.getNextBucket(bucket);
            if (bucket.getUid() == uid) {
                // in some devices this is immediately looping twice
                // and the second iteration is returning correct value.
                // So result is returned in the end.
                usage = (bucket.getRxBytes() + bucket.getTxBytes());
            }
        } while (networkStatsByApp.hasNextBucket());

    } catch (RemoteException e) {
        e.printStackTrace();
    }

    return usage;
}

On application start just save total result, then after desired interval substract total usage with your saved value and you have got the result. ( don't forget to save new result ).