public async Task GetPhotos() { if (IsBusy) { return; } Exception error = null; try { IsBusy = true; var items = await mobileService.GetPhotos(); Photos.Clear(); foreach (var item in items) { Photos.Add(item); } } catch (Exception ex) { Debug.WriteLine("Error: " + ex); error = ex; } finally { IsBusy = false; } if (error != null) { dialogService.ShowError("Error! " + error.Message + " OK"); } }