title: Binding to Source property of Frame doesn't work after Frame.GoBack
body: <p>I have three pages, and to navigate to each page, I'm binding a property to the Source property of the Frame. It works pretty fine if I just navigate the pages normally, but after calling the GoBack method, the Frame suddenly stopped working. If I set a uri to the Source property directly instead of using binding, it works fine though, I'm actually implementing using MVVM, so I don't want to set the Source property directly.</p>
  
  <p>--xaml--</p>
  
  <pre><code>  &lt;navigation:Frame x:Name="_frame" Source="{Binding CurrentPage}"/&gt;
  </code></pre>
  
  <p>--Code behind--</p>
  
  <pre><code>    Uri _currentPage;
      public Uri CurrentPage
      {
          get { return _currentPage; }
          set
          {
              _currentPage = value;
              if (PropertyChanged != null)
                  PropertyChanged(this, new PropertyChangedEventArgs("CurrentPage"));
          }
      }
  
      // back
      private void Button_Click(object sender, RoutedEventArgs e)
      {
          if ( _frame.CanGoBack)
              _frame.GoBack();
      }
  
      // test1
      private void Button_Click_1(object sender, RoutedEventArgs e)
      {
          CurrentPage = new Uri("/TestPage1.xaml", UriKind.Relative);
      }
  
      // test2
      private void Button_Click_2(object sender, RoutedEventArgs e)
      {
          CurrentPage = new Uri("/TestPage2.xaml", UriKind.Relative);
      }
  
      // test3
      private void Button_Click_3(object sender, RoutedEventArgs e)
      {
          CurrentPage = new Uri("/TestPage3.xaml", UriKind.Relative);
      }
  </code></pre>
  
  <p>Does anyone know how to work around this problem? I've tried several ways, but nothing works for me.</p>
  
  <p>Thanks in advance, <br>
  Yoo</p>