Windows Store应用程序的多线程

Question

We are currently creating a Windows Store Application which gains information from an RSS feed and inputs this information into an ObservableCollection. The issue we are having is when the information is being gained, the Applications UI becomes unresponsive.

In order to get around this, I thought about creating a new thread and calling the method within this. Though, after some research we realised that this was no longer possible in Windows Store Apps. How can we get around this?

The method that collects the information is below.

public void getFeed()
{
    setupImages();
    string[] feedUrls = new string[] {
        "http://www.igadgetos.co.uk/blog/category/gadget-news/feed/",
        "http://www.igadgetos.co.uk/blog/category/gadget-reviews/feed/",
        "http://www.igadgetos.co.uk/blog/category/videos/feed/",
        "http://www.igadgetos.co.uk/blog/category/gaming/feed/",
        "http://www.igadgetos.co.uk/blog/category/jailbreak-2/feed/",
        "http://www.igadgetos.co.uk/blog/category/kickstarter/feed/",
        "http://www.igadgetos.co.uk/blog/category/cars-2/feed/",
        "http://www.igadgetos.co.uk/blog/category/software/feed/",
        "http://www.igadgetos.co.uk/blog/category/updates/feed/"
    };

    {
        try
        {
            XNamespace dc = "http://purl.org/dc/elements/1.1/";
            XNamespace content = "http://purl.org/rss/1.0/modules/content/";

            foreach (var feedUrl in feedUrls)
            {
                var doc = XDocument.Load(feedUrl);
                var feed = doc.Descendants("item").Select(c => new ArticleItem() //Creates a copy of the ArticleItem Class.
                {
                    Title = c.Element("title").Value,
                    //There are another 4 of these.
                    Post = stripTags(c.Element(content + "encoded").Value)                        }
                ).OrderByDescending(c => c.PubDate);
                this.moveItems = feed.ToList();

                foreach (var item in moveItems)
                {
                    item.ID = feedItems.Count;
                    feedItems.Add(item);
                }
            }
            lastUpdated = DateTime.Now;
        }
        catch
        {
            MessageDialog popup = new MessageDialog("An error has occured downloading the feed, please try again later.");
            popup.Commands.Add(new UICommand("Okay"));
            popup.Title = "ERROR";

            popup.ShowAsync();
        }
    }
}

How would we be able to cause the Application to not freeze as we gain this information, as Threading is not possible within Windows Store Applications.

Eg - We planned to use;

Thread newThread = new Thread(getFeed);
newThread.Start

Answer 1

You need to use the well documented async pattern for your operations that happen on the UI thread. The link given by Paul-Jan in the comments is where you need to start. http://msdn.microsoft.com/en-us/library/windows/apps/hh994635.aspx