public override void LoadView() { base.LoadView(); this.View = new UIView(); this.View.BackgroundColor = UIColor.Gray; var btn = new UIButton(UIButtonType.RoundedRect); btn.AutoresizingMask = UIViewAutoresizing.FlexibleDimensions; btn.SetTitle("nav start", UIControlState.Normal); this.View.AddSubview(btn); this.NavigationItem.Title = "nav start"; btn.TouchUpInside += delegate(object sender, EventArgs e) { var center = new NavCenter(); // behaviour = integration this.PresentViewController(new UINavigationController(center), true, null); }; }