data usage of app

datausage.java

ActivityManager manager = (ActivityManager) activity.getSystemService(activity.ACTIVITY_SERVICE);
List<ActivityManager.RunningAppProcessInfo> runningApps = manager.getRunningAppProcesses();
Log.i("TAG", "onCreate: " + runningApps.size());
for (ActivityManager.RunningAppProcessInfo runningApp : runningApps) {
    // Get UID of the selected process
    int uid = runningApp.uid;
    // Get traffic data
    long received = TrafficStats.getUidRxBytes(uid);
    long send = TrafficStats.getUidTxBytes(uid);
    Log.v("bytes" + uid, "Send :" + send + ", Received :" + received);
}