/// <summary>
 /// Navigates to the most recent item in back navigation history.
 /// </summary>
 public void GoBack()
 {
     if (CanGoBack)
     {
         _navigationService.GoBack();
     }
 }
 public void GoBack()
 {
     if (EnsureMainFrame() &&
         _mainFrame.CanGoBack)
     {
         _mainFrame.GoBack();
     }
 }