public override async Task SetItemsViewerRegistrationAsync(bool register)
        {
            foreach (var item in Items)
                if (register)
                    await item.RegisterViewerAsync();
                else
                    await item.UnregisterViewerAsync();

            SelectedItem = null;
        }
        protected override void OnNavigatedFrom(NavigationEventArgs e)
        {
            base.OnNavigatedFrom(e);

            if (e.NavigationMode == NavigationMode.Back)
            {
                if (FeedbackModule != null)
                {
                    FeedbackModule.UpdateAsync();
                    FeedbackModule = null;
                }

                AppManager.EcosModel.FeedbackManager.ItemRemoved -= FeedbackManager_ItemRemoved;
            }
        }
 private void RegisterItemNotifications(FeedbackModule item)
 {
     if (item != null)
     {
         item.CommandError += (object sender, MessageEventArgs e) =>
         {
             if (!item.ProcessCommandError(e.Message))
                 NotifyCommandError(e.Message);
         };
     }
 }