title: How save and use navigation context of current part of Panorama Page?
body: <p>In my panorama Page I can find out what part of panorama is now watching by user:</p>
  
  <pre><code>  void DialogPanorama_SelectionChanged(object sender, SelectionChangedEventArgs e)
              {
  
                  FeedItemViewModel feedItem = null;
                  if (e.AddedItems.Count &gt; 0)
                  {
                      feedItem = e.AddedItems[0] as FeedItemViewModel;
                      if (feedItem != null) NavigationContext.QueryString["ITEM_ID"] = feedItem.FeedMessage.Guid;
                  }
  
              } 
  </code></pre>
  
  <p>I have tried to change  NavigationContext.QueryString["ITEM_ID"], but then I need to use this Uri in App.xaml.cs, How can I do this?</p>