PArt 3 of my series on Prism 4 is now live on the Silverlight Show here. This one drills down into CompositeCommands and Prism pub/sub events with the EventAggregator. I show how to use CompositeCommands to hook up loosely coupled parts of the app but still have the enable/disable functionality that commands off that events do not. Then I show using Prism events to keep two loosely coupled parts of the user interface synchronized without them needing to know about each other.

Check it out!

I’ve started a new article series on The Silverlight Show site that will be covering Prism 4 end to end over about 5-6 articles. The first installment is up: Working with Prism 4 Series Part 1 – Getting Started. This one covers the broad concepts of what Prism is for, what features it offers, and walks you through putting together a basic Prism app with one module and plugging a view into a region.

I should be putting a new installment up every two weeks. In the next article, I’ll be putting a little more functionality into a couple of views, including using commands and the MVVM pattern, and communicating between the view with Prism loosely coupled events. After that I will expand on using region navigation, implementing custom module loaders, and other aspects.

Hope you check it out!

My class is now confirmed for 28 Nov – 2 Dec with our training partner Benchmark Learning, but there are still seats available. You can find the full syllabus and registration information here:

http://www.benchmarklearning.com/Courses/CrsDetail.aspx?C=IDWPFMaster

Sign up now!

Two more talks today at DevConnections. One showing an approach to combining MEF, MVVM, and Prism for maximum desktop client extensibility and one showing how to get the most out of Silverlight validation for data entry.

You can grab the slides and demos here:

Desktop Client Extensibility   Slides    Demos

Silverlight Validation    Slides    Demos

Today I am giving two talks at DevConnections. One that compares and contrasts WCF, WCF Data Services, WCF RIA Services, and WCF Web API. The other focuses on Async – the Parallel frameworks, Task Parallel Library, and the Async CTP.

Here are the slides and demos for those who want them:

WCF Flavors – Slides    Demos

Async – Slides   Demos

Today I gave the keynote for the NOVA CodeCamp, in which I focused on the new features of Silverlight 5 and what’s coming with Win 8 and WinRT / Metro development. I covered XAML enhancements, security, text improvements, graphics, 3D, and other features of Silverlight 5. Then I summarized what Windows 8 is all about and what WinRT and Metro are and how they relate to Silverlight and other development technologies for the Microsoft platform in use today.

You can grab the slides and demos here:  Slides    Demos

Last night I gave a talk at the Capital Area .NET Users Group (http://caparea.net) summarizing the announcements and new technologies coming out from the BUILD conference. We had a good crowd and great interaction with lots of questions as people tried to grok Windows 8, WinRT, and Metro and what it really meant to the kinds of apps they are building today. About half the crowd had not watched any of the videos from the conference, so they were starting with a clean slate in terms of understanding the new stuff, which made it interesting to see the kinds of questions I got.

I had a pretty simple slide deck and spent most of the time demoing things and discussing the concepts and implications, but here are the slides for anyone who is interested.

Slides

There is a ton of discussion going on around the announcements at //BUILD/ this week and what the implications are for Silverlight developers and for the future of Silverlight itself. A lot of that speculation has quickly sped to the realm of FUD. As a Silverlight MVP, I for one thing the future is quite bright and shiny for Silverlight developers, and even for Silverlight applications in terms of moving to the new platform and building Metro style applications.

If you have no idea what a “Metro style” application is or what WinRT is, you have lots to read. The short story is that a WinRT application is one built for codename Windows 8, and one that runs with the new user interface style and experience called Metro. Just go check out some of the many videos available now of Windows 8 to get a better sense of what this means. But from a developer perspective, it mean you build a client app to run against the new Windows runtime (WinRT), and it is not a .NET Framework application. There is a lot more to say there, but that is for other posts. What I want to focus on here is what it means at a high level for Silverlight developers.

If you are a Silverlight developer, here are a set of characteristics of your application that you have to deal with on every Silverlight app you write because they are part of the platform:

• It is a XAML-based user interface application, with code behind in C# or VB
• The XAML that you use is a constrained set of XAML compared to WPF – there are some capabilities missing, even in SL5
• It runs in a security constrained sandbox by default, with constrained access to underlying machine capabilities
• Anything in the platform API (Silverlight) that might take “a while” is only exposed as an Async API

So what are some of the things we can say about developing Metro apps at a high level? These same exact statements about the platform hold true for Metro, they just have some slightly different manifestations. This means that not only will developing applications for Windows Metro feel familiar and comfortable to Silverlight developers, more of their code will be portable to Metro applications than other .NET UI applications.

Now I am not saying your Silverlight apps are going to “just run” or that you won’t have to do some non-trivial porting to turn a Silverlight application into a Metro application, but there will be a lot less impedance mismatch there than there will be for your typical WPF or Windows Forms application. Those applications will likely have tons of code that is doing synchronous things that have to become async, and probably also use parts of the .NET Framework capabilities that just wont exist in WinRT, at least for the first release.

However the kinds of capabilities that are in the Silverlight plug in and its supporting libraries are exactly the kinds of things that WinRT will support, just with different namespaces, type names, and some different API member names and arguments.

So the kinds of things you will have to change to port your application if it is well designed will include:

• XAML – there are new controls to comply with the Metro look and feel, but they follow very similar patterns to existing ContentControl and ItemsControl derived controls in Silverlight
• Code that touches the Silverlight framework APIs themselves – but this should be fairly straightforward if you are not too exotic in what you do
• Any COM/PInvoke code

So while it is not going to be “just a weekend project” to port a significant Silverlight application to Metro, a well designed and layered Silverlight application should also not be anything close to a total rewrite. Significant parts of things like model objects, view models, service calls, and application logic should just recompile to WinRT. Significant parts of your XAML and XAML resources can probably still be used as-is. The rest should have fairly straightforward porting paths since the underlying platforms are really very similar.

Now I should caveat this with the fact that I have not sat down and done a significant port of any Silverlight apps I have yet to validate this perspective. I plan to dig into that over the next few weeks and will definitely continue to share my perspectives. But at least from what I have seen at the conference, I’m not sweating it. I like what I see and I am looking forward to continuing to use the skills I have invested in Silverlight and WPF to start building Metro apps.

Last night I gave an overview talk on WCF RIA Services. I covered what RIA Services is for, what the features are and spent most of the time demonstrating those features. I went through basic query and update with RIA services, validating data, and securing and personalizing your app.

You can find the slides and demos for that session here:

Slides

Demos

I’ll be giving a talk on WCF RIA Services at the Twin Cities Developers Group in Edina MN near Minneapolis on 8/9/2011. This will be an overview talk on the capabilities of WCF RIA Services for querying and updating data, validating input data, and securing Silverlight applications. You can find the full details on their registration page. If you are in the area, I hope to see you there!

http://www.twincitiesdevelopersgroup.com/2011/07/15/accelerate-silverlight-business-app-development-with-wcf-ria-services/