Return data to Silverlight UI from Silverlight Class Library

Question

I am about to refactor my code where i am splitting up my code in UI-BAL-DAL layers.

Now have two silverlight class libraries and one Silverlight UI app. i.e. BAL(Business access layer) and DAL(Data access layer). My UI layer talks to BAL and BAL internally talks with DAL..so UI does`nt know anything about DAL. I am using sharepoint 2010 search service which i am calling from DAL and i need to return the data to BAL the BAL will process the data and return the data in form of class collection to UI layer. But how can i achieve this as the service is async.

Answer 1

You need to expose the DAL interface as asynchronous as well. The BAL would call some asynchronous operation on the DAL, and this one would fire the async call to the sharepoint service. When you get a completion (or an event) from the call to the service, you'd notify the original caller (BAL, in your case) that the data is ready to be retrieved.

Answer 2

On other side, if You are using BAL as Service (Web/WCF), which will talk to DAL. So you can handle all responses from BAL to UI. there are lots of articles flooding around. and it is irrespective of sharepoint 2010