private async Task ExecuteAddGroupCommandAsync() { try { if (string.IsNullOrEmpty(GroupToAdd)) { throw new ArgumentNullException(nameof(GroupToAdd), "Please enter a group name."); } //Remember which group was selected by its unique ID var tempSelectedGroupId = SelectedPersonGroup.PersonGroupId; await FaceService.CreatePersonGroupAsync(Guid.NewGuid().ToString(), GroupToAdd); await(new MessageDialog($"'{GroupToAdd}' successfully added.")).ShowAsync(); //Cleanup UI GroupToAdd = string.Empty; await LoadGroupsAsync(); //Set the selected group back to the group we had selected before foreach (var group in PersonGroups) { if (group.PersonGroupId.Equals(tempSelectedGroupId)) { SelectedPersonGroup = group; break; } } } catch (Exception ex) { var dialog = new MessageDialog(ex.Message, "Group could not be added."); await dialog.ShowAsync(); } }