private async Task GetContacts() { using (new Loading(this)) { var items = await OfficeService.GetContacts(_curPageIndex, PageSize); Contacts = new ObservableCollection <Contact>(items); var tasks = Contacts.Select(x => SetContactPhoto(x)); await Task.WhenAll(tasks); } HasPrev = _curPageIndex > 0; HasNext = PageSize * (_curPageIndex + 1) < _contactsCount; IsLoading = false; }