protected override void LoadState(Object navigationParameter, Dictionary <String, Object> pageState)
    {
        args = navigationParameter as QuizArgs;
        var SectorGroups = QuizDataSource.GetGroups(args.sector);

        this.DefaultViewModel["Groups"] = SectorGroups;
    }
    void ItemView_ItemClick(object sender, ItemClickEventArgs e)
    {
        if (args == null)
        {
            throw new NullReferenceException();
        }
        var itemId   = args.UniqueId;
        var sectorId = new QuizArgs
        {
            sector   = "nav",
            question = 2,
            Total    = 0,
            type     = itemId
        };

        this.Frame.Navigate(typeof(Quiz), sectorId);
    }