/// <summary>
        /// Preserves state associated with this page in case the application is suspended or the
        /// page is discarded from the navigation cache.  Values must conform to the serialization
        /// requirements of <see cref="SuspensionManager.SessionState"/>.
        /// </summary>
        /// <param name="pageState">An empty dictionary to be populated with serializable state.</param>
        private void navigationHelper_SaveState(object sender, SaveStateEventArgs e)
        {
            if (this.itemsViewSource.View != null)
            {
                // TODO: Derive a serializable navigation parameter and assign it to
                //       pageState("SelectedItem")

            }
        }
 /// <summary>
 /// Preserves state associated with this page in case the application is suspended or the
 /// page is discarded from the navigation cache.  Values must conform to the serialization
 /// requirements of <see cref="SuspensionManager.SessionState"/>.
 /// </summary>
 /// <param name="pageState">An empty dictionary to be populated with serializable state.</param>
 private void navigationHelper_SaveState(object sender, SaveStateEventArgs e)
 {
 }