private void lbxFeedItems_SelectionChanged(object sender, SelectionChangedEventArgs e)
 {
     SelectedFeedItem = e.AddedItems.Count > 0 ? e.AddedItems.Cast<FeedItem>().First() : null;
     scrFeedItem.Visibility = SelectedFeedItem != null ? Visibility.Visible : Visibility.Collapsed;
 }
 public FeedItemViewer(FeedItem feedItem)
 {
     FeedItem = feedItem;
     InitializeComponent();
 }