public ModalWindowController(string startUri, string endUriRoot) : base("ModalWindow") { StartUri = startUri; EndUriRoot = endUriRoot; Result = null; ModalDelegate = new WindowDelegate(() => { App.AbortModal(); }); NavigationDelegate = new NavDelegate(d => { if (d.StartsWith(EndUriRoot, StringComparison.InvariantCultureIgnoreCase)) { Result = d; Window.Close(); } }); }