private async Task QueryFollowings() { if (followingPage == 1) { if (FollowingUsers == null) { FollowingUsers = new ObservableCollection <FollowUser>(); } else { FollowingUsers.Clear(); } } UserContentProvider user = new UserContentProvider(); List <FollowUserInfo> result = await user.QueryFollowingUsers(followingPage, currentUserId, GlobalValue.CurrentUserContext.UserId, GlobalValue.CurrentUserContext.MobileToken); result.ForEach(x => FollowingUsers.Add(ConvertToFollowUser(x))); followingPage++; if (FollowingUsers.Count <= 10 && followingPage == 2) { await QueryFollowings(); } }