public class CheckInternetConnectAsyncTask extends AsyncTask<Void, Void, Boolean> {

    private final WeakReference<MainActivity> activityWeakReference;

    public CheckInternetConnectAsyncTask(MainActivity activity) {
        this.activityWeakReference = new WeakReference<>(activity);
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();

        MainActivity activity = activityWeakReference.get();
        if (activity != null) {
            ProgressBar progressBar = activity.findViewById(R.id.progress_bar);
            progressBar.visibility(View.VISIBLE);
        }
    }

    @Override
    protected Boolean doInBackground(Void... voids) {
        return NetworkUtils.isInternetConnected();
    }

    @Override
    protected void onPostExecute(Boolean isConnected) {
        super.onPostExecute(isConnected);
        MainActivity activity = activityWeakReference.get();
        if (activity != null) {
            if (isConnected) {
                  //handle
            } else {
                ProgressBar progressBar = activity.findViewById(R.id.progress_bar);
                progressBar.visibility(View.GONE);

                CoordinatorLayout parentLayout = activity.findViewById(R.id.coordinator_layout);
                Utils.showSnackbar(parentLayout, activity.getString(R.string.no_internet));
            }
        }
    }
}