private void NextNavCommandHandler()
        {
            RoleListView.MoveCurrentToNext();

            if (RoleListView.IsCurrentAfterLast == true)
            {
                RoleListView.MoveCurrentToLast();
            }

            SelectedRole = (RoleModel)RoleListView.CurrentItem;
        }
 private void LastNavCommandHandler()
 {
     RoleListView.MoveCurrentToLast();
     SelectedRole = (RoleModel)RoleListView.CurrentItem;
 }