/// <summary>
/// Called when we are leaving the page.
/// We clear the constructorCalled flag so that we will be able to
/// determine if we were tomb stoned or not if we receive an activation event
/// </summary>
/// <param name="e">Event Data</param>
protected override void OnNavigatedFrom(NavigationEventArgs e)
{
base.OnNavigatedFrom(e);
this.viewModel.SyncStateToAppState(this.viewModel.SelectedDataIndex);
ApplicationState.AddAppObjects(true);
}