private void UpdateSlackUsers()
        {
            var slackUserRepository = ServiceLocator.Instance.GetInstance <SlackUserRepository>();

            SlackUsers.Clear();
            var slackUsers = slackUserRepository.FindAll();

            slackUsers.ForEach(user => SlackUsers.Add(user));

            if (SelectedSlackUser != null)
            {
                var token = SelectedSlackUser.AccessToken;
                SelectedSlackUser = SlackUsers.ToList().Find(user => user.AccessToken == token);
            }
        }
        public void OnClose()
        {
            //現在の状態を保存
            var slackUserRepository = ServiceLocator.Instance.GetInstance <SlackUserRepository>();

            slackUserRepository.Save(SlackUsers.ToList());

            //差分からアカウントを削除
            var diff = new List <SlackUser>(_oldSlackUsersList);

            foreach (var twitterUser in SlackUsers)
            {
                diff.Remove(twitterUser);
            }
            slackUserRepository.Delete(diff);
        }