ASP.NET AJAX Team Blogs : Silverlight

ViewModel Pattern for Silverlight - Options for Hooking a View to its Model

Nikhil Kothari's Weblog — Fri, 11 Dec 2009 17:42:15 GMT

In the ViewModel, aka the MVVM pattern, a view such as a UserControl is bound to its associated view model. The view model manages state exposed as observable properties, operations exposed as methods and raises notifications via events. An interesting question is how a View should specify its view model, and how a view model instance should be created. Like everything else in the ViewModel pattern, this topic is no different. There are different strategies, with pros and cons, and different people have different opinions. In this post, I'll describe a couple of options, and hope to collect some feedback as well as ideas on alternatives. Part of my goal here is to improve what is supported in Silverlight.FX out-of-the-box. The other goal...(read more)

RIA Services Link Listing #1

Nikhil Kothari's Weblog — Mon, 07 Dec 2009 17:10:43 GMT

Starting a new link listing series around interesting posts/content related to RIA Services. Hope you find these useful, and if you'd like to share something please send them along... [ Full post continued here... ] Read More......(read more)

Bing Maps roadshow in Reston

Public Sector Developer Weblog : AJAX — Mon, 30 Nov 2009 15:27:13 GMT

NOTE: This was cross posted from here . Want to get up to speed on the latest release of Bing Maps including both the Ajax and Silverlight controls as well as the SOAP web services? Don’t miss the upcoming roadshow in Reston, Va. Details: http://www.bing.com/community/blogs/govmaps/archive/2009/11/24/bing-maps-roadshow-coming-to-reston-virgina.aspx “At this event, experts will provide an overview of Bing Maps as a powerful visualization tool for geographic and location-based information. With highlights of scenarios such as locators, fleet/asset tracking, data visualization portals, and location intelligence, we’ll present a deep dive into the Bing Maps Platform, including details on specific features, AJAX, Web Services, and new...(read more)

RIA Services: Jumpstarting RIA Development

Nikhil Kothari's Weblog — Thu, 19 Nov 2009 09:03:31 GMT

In my post on RIA Services: From Vision to Architecture , a while back (right after MIX09), I mentioned that I like to think of RIA Services as RAD for RIA. At that point we had a very early preview of framework bits with little tools support. A large part of jumpstarting your development actually centers around good tooling. VS2010 brings tooling for RIA Services (now: WCF RIA Services). Scott Hanselman demonstrated some key features used in building a Contacts application (as shown on the right) during the keynote at PDC09 . The latest version of RIA Services is now available for download. It works on .NET 4 and VS2010 as well. You can also check out a video tutorial on using RIA Services and Visual Studio 2010. In this post, I want to highlight...(read more)

Silverlight 4 Debuts with Killer Demos at PDC09

Nikhil Kothari's Weblog — Wed, 18 Nov 2009 22:35:44 GMT

Lots of wow from this morning with Silverlight 4 (and RIA Services) taking center stage in the keynote, here at PDC09. [ Full post continued here... ] Read More......(read more)

Fluent API for .NET RIA Services Metadata

Nikhil Kothari's Weblog — Mon, 21 Sep 2009 04:34:10 GMT

.NET RIA Services relies heavily on metadata annotations for expressing intent beyond what can be inferrd via convention. For example, validation rules on entities and members can be declared as annotations, which then enable a variety of consumption scenarios. We also have metadata for describing model aspects in DAL-agnostic fashion, and hints for automatic UI-generation. What we have today is just a first step. The general design we're enabling is actually quite flexible. For example, a number of developers want to have metadata specified external to their code, for example in XML files or in a database. Some don't like attributes, and have asked for a fluent interface instead. In RIA Services, we wanted to create a consistent API...(read more)

Dialogs and ViewModel - Using Tasks as a Pattern

Nikhil Kothari's Weblog — Fri, 11 Sep 2009 16:37:28 GMT

The ViewModel/MVVM pattern continues to gain popularity, with a blog post showing up every so often, and with tweets and retweets popping up even more often :-). At the same time, there are some interesting topics beyond the core pattern that continue to fuel experimentation. A big one amongst those is how should applications use dialogs when using the view model pattern. The crux of the problem is the desire to keep the view model independent of UI concerns, and ensure it can be tested in a standalone manner, but that often comes to odds when you want the view model to launch a dialog, and/or do some work after the dialog is closed. The most recent version of Silverlight.FX (v3.2) that I published earlier this week, addresses this scenario...(read more)

BouncingPlane Behavior for Silverlight

Nikhil Kothari's Weblog — Thu, 27 Aug 2009 23:15:22 GMT

Time for a brief but fun post... some time back Tim Heuer posted the Silverlight 3 bouncing plane gratuitous demo . Click an element, and the nearest corner would bounce backwards and forwards as it comes back to rest. Tim had the code to setup the storyboards, and handle the mouse interaction in code-behind. I look at it, and immediately see a reusable component (even if it is a gratuitous one), or more specifically a behavior, that encapsulates all the logic, and can be attached declaratively in XAML to one or more elements simply without needing any code-behind logic. So I created one such behavior. I used this behavior in my TwitterBug sample at TechEd recently, and thought it could use a dedicated blog post. :-) Here is a screenshot, which...(read more)

LINQ to Bing, Silverlight and .NET RIA Services

Nikhil Kothari's Weblog — Wed, 26 Aug 2009 18:20:20 GMT

In my last post, I described BLinq, or LINQ to Bing , an API that allows you use LINQ to access the Bing search results (ok, so perhaps BLinq was not the best of names, given prior art on that name ... but anyway). I also alluded to .NET RIA Services integration, which I'll cover in this installment. In fact, IQueryable and the LINQ pattern lie at the very heart of .NET RIA Services, in allowing developers to access data in a consistent manner not just on client or server but across client and server, and enabling code to compose queries naturally. If you haven't read the intro post, please take the few minutes to check out the LINQ snippets to get a general sense before continuing on. You might use Bing in your rich internet application...(read more)

TechEd South Africa Slides and Code - .NET RIA Services and ViewModel

Nikhil Kothari's Weblog — Tue, 04 Aug 2009 22:02:26 GMT

This is a quick blog post to share slides and demos from my presentations at TechEd in South Africa. Feel free to post questions here... From the talk on ViewModel and Application Patterns for Silverlight... The app I built was a mini-Twitter client named TwitterBug. The demo covered the following: The ViewModel pattern using data-binding and commanding Behaviors as a mechanism to encapsulate repetitive view functionality Implementing an IoC container and dependency injection using MEF EventAggregator pattern to facilitate view model to view model communication Designer/developer workflow Unit testing of view models Using .NET RIA Services and building a DomainService that uses LINQ to Twitter as its DAL .NET RIA Services… For this session I...(read more)

.NET RIA Services Twitter Pitch

Nikhil Kothari's Weblog — Thu, 23 Jul 2009 18:00:14 GMT

There is the well-known elevator pitch - can you describe something while riding in an elevator? Now we have the twitter pitch - what can you describe in 140 characters? Here was a question on twitter from yesterday: Can someone explain in 140 characters or less what .Net RIA Services is? And Brad tweeted his response: @ hotgazpacho How is this: .NET RIA Services makes writing n-tier silverlight apps much easier! @ nikhilk do you want to take a shot? So I did, with my tweet : @ hotgazpacho # RIAServices simplifies RIA & Web app development by prescribing patterns for writing app logic & providing out-of-box app svcs Now if I had a little more time, in the case of an elevator pitch, say we got out on the same floor and were continuing...(read more)

Silverlight and Making a Statement on Twitter

Nikhil Kothari's Weblog — Sun, 19 Jul 2009 14:03:10 GMT

A little bit of weekend fun with Twitter and your avatar image... using Twibbon to spread the Silverlight "Light up the Web" message... [ Full post continued here... ] Read More......(read more)

Silverlight.FX Updated for Silverlight 3

Nikhil Kothari's Weblog — Fri, 17 Jul 2009 06:37:04 GMT

First build of Silverlight.FX on top of Silverlight 3 with updates/enhancements ready - new features include ApplicationContext class, new Float/Spin3D effects, and Back/Forward integration. [ Full post continued here... ] Read More......(read more)

Silverlight 3 + .NET RIA Services July Preview

Nikhil Kothari's Weblog — Fri, 10 Jul 2009 17:28:47 GMT

Silverlight 3 is here!!! The Silverlight platform has come a long way (in a relatively short period of time) from a scriptable graphics and media runtime into a full-fledged platform for developing Rich Internet Applications, using managed code, the goodness of application frameworks and controls, and great tools such as Visual Studio and Expression. In my MIX ’09 post , I listed the following: Graphics and Media Capabilities - GPU support, perspective transforms, pixel shader effects, media smooth streaming, new codecs, including ability to write your own, better text rendering, etc. Data - Lots of new data controls (such as DataForm), data-binding improvements, and validation. Application model - ability to use library cache for reducing xap...(read more)

ViewModel with MVC/Navigation in Silverlight

Nikhil Kothari's Weblog — Sat, 30 May 2009 16:13:46 GMT

I've been writing about ViewModel (aka MVVM) pattern ( here , here , here and more) and implementing it in Silverlight.FX for quite some time now, and it continues to be an exciting area for further thinking, and prototyping. This time around I want to cover how ViewModel and MVC fit together in an application at the same time. I have put together a set of navigation features into Silverlight.FX: a Page base class, a PageFrame control, and a Navigate trigger action. The PageFrame class by default maps URIs to Page types automatically, but at the same time supports plugging in an MVC PageLoader that maps URIs to Controllers and Actions, and maps ActionResults resulting from those actions into visuals or Pages. Specifically the controller...(read more)