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Toaday I got a comment from a blog reader named Fracisco…I think he wanted to know how to load new pages into a Silverlight website.  Just for him, and because I think many of you have the same problem, I made a video tutorial where I show you how to:

1. Create a Content Holder UserControl;

2. Make two pages called HomePage and AboutUs;

3. In App.xaml load ContentHolder instead of MainPage.xaml (the default action of a SL app) [...]

In the last part of the series, I thought I was done with the example and some of my readers challenged me to help them understand how to handle Add/Delete scenarios. Since I was at it, I figured I should show paging and IsDirty scenarios as well, I decided to make a part four. 

Silverlight 3 includes PagedCollectionView class, which provides UI-level grouping, sorting and paging functionality for any data source that implements the IEnumerable interface. This works as long as all the data that you need to sort, page are already fetched to the client which could be a slow process and can potentially consumed lots of memory on the client-side. A better solution is to provide Server-side sorting & paging. 

Silverlight 3 includes PagedCollectionView class, which provides grouping, sorting, and paging functionality for any data source that implements the IEnumerable interface. This works as long as all the data that you need to sort (and/or page) is already fetched to the client. However when you are retrieving only a limited set of data from the server at a time, you need an alternative solution that does sorting on the server.

By itself, this is a fairly trivial problem to overcome, however, I had a few additional constraints that change the nature of the problem completely.

Constraint #1: Instead of scrolling, the layout must display whatever possible in the available height, and the remaining items should appear on subsequent pages.

Constraint #2: Each item will consist of a header and a variable number of sub items.  If there is no remaining space to display sub items on the current page, the items should appear on the next page, along with the appropriate header. [...]

Maurice de Beijer demonstrates how to use the DomainDataSource in the .NET RIA Services app.

Using the declarative DomainDataSource that is part of the upcoming Silverlight 3 RIA services makes it quite easy to work with data. All you need to do is add a DomainDataSource control to the the XAML, point it to the generated DomainContext class (in this case NorthwindContext) and tell it which method to use to load the data from the web service(in this case LoadCustomers).