c# - (HRESULT からの例外: 0x8001010E (RPC_E_WRONG_THREAD))

Question

ObservableCollection を ListBox に関連付けようとしましたが、次のエラーが表示されます: The application called an interface That was marshalled for a different thread. ( Exception from HRESULT: 0x8001010E (RPC_E_WRONG_THREAD))

Prueba.cs クラスには、次のものがあります。

  public ObservableCollection<WidgetCollectionItem> WidgetsDownloaded(string e)
    {
        int alertas = 0;

        XDocument document = XDocument.Parse(e);

        // Obtener el id
        //id = document.Root.Element("id").Value;

        ObservableCollection<WidgetCollectionItem> Items = new ObservableCollection<WidgetCollectionItem>();
        foreach (XElement wid in document.Root.Elements("widget"))
        {
            WidgetCollectionItem widget = new WidgetCollectionItem();
            widget.captionWid = wid.Attribute("caption") != null ? wid.Attribute("caption").Value : null;

            ObservableCollection<ServiciosWidgetCollectionItem> ItemsSer = new ObservableCollection<ServiciosWidgetCollectionItem>();
            widget.ItemsSer = ItemsSer;

            foreach (XElement service in wid.Elements("service"))
            {
                ServiciosWidgetCollectionItem ser = new ServiciosWidgetCollectionItem();

                ser.captionWid = wid.Attribute("caption") != null ? wid.Attribute("caption").Value : null;
                ser.nameWid = wid.Attribute("name") != null ? wid.Attribute("name").Value : null;
                ser.nameSer = service.Attribute("name") != null ? service.Attribute("name").Value : null;
                ser.captionSer = service.Attribute("caption") != null ? service.Attribute("caption").Value : null;
                ser.descripcion = service.Attribute("desc") != null ? service.Attribute("desc").Value : null;
                ser.valor = service.Element("xvalue") != null ? service.Element("xvalue").Value : null;
                ser.color = service.Element("xcolor") != null ? service.Element("xcolor").Value : null;
                ser.alerta = service.Element("xalert") != null ? service.Element("xalert").Value : null;
                if (ser.alerta != null) { alertas++; }

                ItemsSer.Add(ser);
            }
            Items.Add(widget);
        }
        return Items;
    }




 public class ServiciosWidgetCollectionItem
    {
        public string captionWid { get; set; }
        public string captionSer { get; set; }
        public string nameWid { get; set; }
        public string nameSer { get; set; }
        public string descripcion { get; set; }
        public string valor { get; set; }
        public string color { get; set; }
        public string alerta { get; set; }
    }

    public class WidgetCollectionItem
    {
        public string captionWid { get; set; }
        public ObservableCollection<ServiciosWidgetCollectionItem> ItemsSer { get; set; }
    }

MainPage からページに接続すると、プロセス全体が正常に機能しますが、ListBox ItemsSouces を挿入するとエラーが表示されます。

public MainPage()
    {
        this.InitializeComponent();

        Prueba prueba = new Prueba();

        var request = (HttpWebRequest)WebRequest.Create(new Uri(ruta));
        request.BeginGetResponse(r =>
        {
            var httpRequest = (HttpWebRequest)r.AsyncState;
            var httpResponse = (HttpWebResponse)httpRequest.EndGetResponse(r);

            using (var reader = new StreamReader(httpResponse.GetResponseStream()))
            {
                var response = reader.ReadToEnd();

                widgetsList.ItemsSource = prueba.WidgetsDownloaded(response);
            }
        }, request);
    }