protected override void PopulateEditModel(EditVM model, ref bool valid)
        {
            if (valid == true)
            {
                if (!AuthenticationManager.LoggedUser.IsAdmin)
                {
                    model.UserId = AuthenticationManager.LoggedUser.Id;
                }

                if (model.UserId == 0)
                {
                    model.UserId = AuthenticationManager.LoggedUser.Id;
                }

                ActivitiesRepository repo = new ActivitiesRepository();
                model.activity = repo.GetById(model.ActivityId);
                if (model.activity != null)
                {
                    model.Title = model.activity.Name;
                    if (model.StartDateTime != null)
                    {
                        TimeSpan duration = TimeSpan.FromHours(model.activity.Duration);
                        model.EndDateTime = model.StartDateTime.Value.Add(duration);
                    }
                }
                else
                {
                    valid = false;
                }
            }
        }