private async Task InitializeCollection() { Task <IEnumerable <long> > reader; switch (_type) { case RelationDataType.Following: reader = UserProxy.GetFollowingsAsync(_parent.AccountId); break; case RelationDataType.Follower: reader = UserProxy.GetFollowersAsync(_parent.AccountId); break; case RelationDataType.Blocking: reader = UserProxy.GetBlockingsAsync(_parent.AccountId); break; case RelationDataType.NoRetweets: reader = UserProxy.GetNoRetweetsAsync(_parent.AccountId); break; case RelationDataType.Mutes: reader = UserProxy.GetMutesAsync(_parent.AccountId); break; default: throw new ArgumentOutOfRangeException(); } await AddAsync(await reader.ConfigureAwait(false)).ConfigureAwait(false); }