private void OnUserProfileListAdd(UserProfile entity)
 {
     SendPropertyChanging(null);
     WebpagesUsersInRolesList.Add(new WebpagesUsersInRoles {
         WebpagesRoles = this, UserProfile = entity
     });
     SendPropertyChanged(null);
 }
        private void OnUserProfileListRemove(UserProfile entity)
        {
            SendPropertyChanging(null);
            var webpagesUsersInRoles = WebpagesUsersInRolesList.FirstOrDefault(c => c.RoleId == RoleId &&
                                                                               c.UserId == entity.UserId);

            WebpagesUsersInRolesList.Remove(webpagesUsersInRoles);
            SendPropertyChanged(null);
        }