public override void ViewDidLoad()
        {
            Title = "Level 2";

            UILabel label = new UILabel();
            label.Text = "Level2ViewController";
            label.Frame = new System.Drawing.RectangleF(100,100,100,100);
            View.AddSubview(label);

            // A new toolbar with items
            UIBarButtonItem item = new UIBarButtonItem();
            item.Title = "Another item";
            item.Clicked += delegate(object sender, EventArgs e) {
                Level3ViewController controller = new Level3ViewController();
                NavigationController.PushViewController(controller,true);
            };

            ToolbarItems = new UIBarButtonItem[] {item};

            base.ViewDidLoad ();
        }
        //        public override void ViewDidLoad ()
        //        {
        //            _firstController = new HomeViewController();
        //            PushViewController(_firstController,true);
        //            
        //            base.ViewDidLoad ();
        //        }
        public override void ViewDidLoad()
        {
            var firstController = new HomeViewController();
            var secondController = new Level2ViewController();
            var thirdController = new Level3ViewController();

            var viewControllers = ViewControllers.ToList();
            viewControllers.Add(firstController);
            viewControllers.Add(secondController);
            viewControllers.Add(thirdController);
            ViewControllers = viewControllers.ToArray();

            base.ViewDidLoad ();
        }