When you are calling a function on a WCF .NET RIA service, the completed eventhandler will take you back to the UI thread, but if you are binding the ListBox to a List<….> the UI of the Listbox won’t be updated.
Solution: don’t use a List<…> as ItemSource but a System.Collections.ObjectModel.ObservableCollection<…>
Tags: Silverlight, WCF RIA Services
