Uri uri = new Uri( feedUri);
SyndicationClient client = new SyndicationClient();
SyndicationFeed currentFeed = await client.RetrieveFeedAsync(uri);
XmlDocument toastXml = ToastNotificationManager.GetTemplateContent(ToastTemplateType.ToastImageAndText03);
XmlNodeList toastTextElement = toastXml.GetElementsByTagName("text");
toastTextElement[0].AppendChild(toastXml.CreateTextNode("Working"));
ToastNotification toast = new ToastNotification(toastXml);
ToastNotificationManager.CreateToastNotifier().Show(toast);
nothing is being executed after RetrieveFeedAsync.
try to add deferal to your Running Background
public async void Run(IBackgroundTaskInstance taskInstance)
{
BackgroundTaskDeferral deferral = taskInstance.GetDeferral();
//YOUR CODE GOES HERE
deferral.Complete();
}