title: add data item to observablecollection?
body: <p>I need to add selected items to this collection..
  I select my item on a page and then appbar appears and i want on the appbar button tapped event to add item to collection that will be displayed on the other page..</p>
  
  <pre><code>private void Button_Tapped_1(object sender, TappedRoutedEventArgs e)
      {
  
          AllActors m = new AllActors();
  
          ActorsObject objkt = itemGridView.SelectedItem;
  
          m.allActors.Add(objkt);
  
      }
  </code></pre>
  
  <p>this doesnt work... here are my classes:</p>
  
  <pre><code>public class AllActors : LivingDataCommon
  { 
  public AllActors()
          : base(String.Empty, String.Empty)
      {
      }
  
      public AllActors(String ID, String title)
          : base(ID, title)
      { }
  
      private ObservableCollection&lt;ActorsObject&gt; _AllActors = new ObservableCollection&lt;ActorsObject&gt;();
      public ObservableCollection&lt;ActorsObject&gt; allActors
      {
          get { return this._AllActors; }
      }
  
  }
  </code></pre>