public MainPage()
 {
     BindingContext = new Checkbook();
     InitializeComponent();
 }
        public MainPage ()
        {
			BindingContext = new Checkbook();
            InitializeComponent ();
        }
        protected override void OnAppearing()
        {
            Checkbook checkbook = (Checkbook)BindingContext;

            checkbook.SelectedCheck = null;
        }