/// <summary>
        /// Initializes a new instance of the <see cref="ItemsControlSampleViewModel"/> class.
        /// </summary>
        public ItemsControlSampleViewModel()
        {
            Title = "Items Control Sample";

            Group1.Add("Homer Simpson");
            Group1.Add("Marge Simpson");
            Group1.Add("Bart Simpson");
            Group1.Add("Lisa Simpson");
            Group1.Add("Maggie Simpson");

            Group2.Add("Mr Burns");
            Group2.Add("Mr Smithers");

            Group3.Add("Krusty");
            Group3.Add("Bubblebee Man");

            group4.Add("Itchy");
            group4.Add("Scratchy");
        }