public override bool OnCreateOptionsMenu(IMenu menu)
        {
            MenuInflater.Inflate(Resource.Menu.spinner, menu);

            var spinnerItem = menu.FindItem(Resource.Id.num_of_folds);
            var spinner     = (Spinner)MenuItemCompat.GetActionView(spinnerItem);

            spinner.ItemSelected += (s, e) =>
            {
                var numberOfFolds = int.Parse(e.Parent.GetItemAtPosition(e.Position).ToString());

                var fold = _drawer.GetFoldingLayout(_drawerList);
                if (fold != null)
                {
                    fold.NumberOfFolds = numberOfFolds;
                }
            };

            return(base.OnCreateOptionsMenu(menu));
        }