/// <summary>
/// Invoked when application execution is being suspended. Application state is saved
/// without knowing whether the application will be terminated or resumed with the contents
/// of memory still intact.
/// </summary>
/// <param name="sender">The source of the suspend request.</param>
/// <param name="e">Details about the suspend request.</param>
private void OnSuspending(object sender, SuspendingEventArgs e)
{
SuspendingDeferral deferral = e.SuspendingOperation.GetDeferral();
DebugHelper.Trace($"Suspending! Deadline: {e.SuspendingOperation.Deadline}. That is {e.SuspendingOperation.Deadline.Subtract(DateTime.Now).TotalSeconds} from now.");
// Save state, e.g., which database file is open (we will prompt to unlock again on restore)
RootView root = RootFrame.Content as RootView;
root.HandleSuspend();
deferral.Complete();
}