Raise an event with the SynchronizationContext in Silverlight

Question

Hello,

I have created a View Model in Silverlight. This View Model has an event defined as:

public event EventHandler Data_Loaded;

I want to "Raise" this event when data from a service call has been completed. This will allow my UI to respond properly. Please note, it is not just a simple binding scenario, that is why I want the event.

The service call is made via a HttpWebRequest. Once this request is done, I'm properly parsing the results. I'm trying to let the UI know that I'm done, but initially I was getting an error that said "Invalid cross-thread access". I spoke to a co-worker who told me I should use the SynchronizationContext.Current to raise an event. Unfortunately, I do not understand how to do this. Can someone please explain it to me?

Answer 1

You need to use the Dispatcher to force the event to be raised on the UI thread.

Deployment.Current.Dispatcher.BeginInvoke(() => DataLoaded(this,EventArgs.Empty));