As Scott Guthrie mentioned, Silverlight 2 Beta2 was released today. You can download both Silverlight 2 Beta2 and the Visual Studio and Expression Blend tools support to target it here.
Beta2 adds a lot of new features (more details below), but is still a 4.6 MB download that takes less than 10 seconds to install on a machine. It does not require the .NET Framework or any other software to be installed for it to work, and all features work cross-browser on both Mac and Windows machines. These features will also be supported on Linux via the Moonlight 2 release.
Silverlight 2 Beta2 supports a go-live license that allows you to start using and deploying Silverlight 2 for commercial applications. There will be some API changes between Beta2 and the final release, so you should expect that applications you write with Beta2 will need to make some updates when the final release comes out. But we think that these changes will be straight-forward and relatively easy, and that you can begin planning and starting commercial projects now.
You can build Silverlight Beta2 applications using the VS 2008 Tools for Silverlight and Expression Blend 2.5 June Preview downloads. You can download both of them here. The VS 2008 Tools for Silverlight download works with both VS 2008 and the recent VS 2008 SP1 beta release.
UI and Control Improvements
Silverlight 2 Beta2 includes a bunch of work in the UI and Control space:
More Built-in Controls
In Beta 1 only a few controls were included with the core Silverlight setup. Most common controls (including Button, ListBox, Slider, etc) were shipped within separate assemblies that you had to bundle with your applications (which increased the app download size). Beta 2 now installs 30+ of the most common controls as part of the core Silverlight 2 download. This means that you can now build Silverlight 2 applications that use core controls that are as small as 3kb in size - making Silverlight application downloads small and startup time fast.
In addition to the core controls included with the base Silverlight 2 setup, we are also this week shipping additional higher-level controls that are implemented in separate assemblies that you can then reference and include with your applications. This includes controls like DataGrid (more details on its new Beta2 features below), Calendar (now with multi-day selection and blackout date support in Beta2), and a TabPanel control (new in Beta2).
We ultimately expect to ship over a 100 controls for Silverlight.
Control Template Editing Support
One of the most powerful features of the WPF and Silverlight programming model is the ability to completely customize the look and feel of controls. This allows developers and designers to sculpt the UI of controls in both subtle and dramatic ways, and enables a tremendous amount of flexibility.
This week's Expression Blend 2.5 June Preview now adds designer support for editing control templates - which makes it easy for you to quickly change the look of any control without having to drop-down to XAML source to-do it.
Visual State Manager (VSM) Support
Control templates in Silverlight and WPF support customizing both the "look" of a control, as well as the "feel" of a control. By "feel" I mean changing its interactive responsiveness. For example: how it reacts when pushed, when it gets focus, loses focus, is in a pushed state, is in a disabled state, has something inside it selected, etc. Often you want animations to execute when the user interacts with a control like this.
One of the new things we are introducing with Silverlight 2 Beta2 is a "Visual State Manager" (VSM) feature that makes it much easier to build interactive control templates. VSM introduces two basic concepts that you can take advantage of within control templates: "Visual States" and "State Transitions". For example, a control like Button defines multiple visual states for itself - "Normal", "MouseOver", "Pressed", "Disabled", "Focused", "Unfocused". When in template editing mode in Blend, designers now have the ability to easily edit what the button looks like in each particular state, as well as setup transition rules to control how long it should take to animate when moving from one state to another. At runtime Silverlight will then dynamically run the appropriate animation Storyboards to smoothly move the control from one state to another.
What is nice about this model is that designers do not need to write code, do not need to manually create animation storyboards, and do not need to understand the object model of controls in order to be productive. This makes the learning curve for creating interactive control templates really easy, and means that existing graphic designers can very easily work on Silverlight projects. Later this year we will also be adding Visual State Manager (VSM) support to WPF as well, which will let you use the same approach with Windows applications as well as share control templates between WPF and Silverlight projects.
To learn more about the new Visual State Manager and Control Template Editing features, please check out the tutorials here and here, and the videos on it here, here, and here.
Beta2 includes some significant improvements to the built-in TextBox editing control. Text scrolling with text-wrap, multi-line text selection, document navigation keys, and copy/paste from the clipboard are now supported.
Beta2 also now includes IME Level 3 input support (including candidate window selection) for non-western character sets.
Beta2 adds additional keyboard support in FullScreen mode (arrow, tab, enter, home, end, pageup/pagedown, space). Note: full key input support isn't allowed to avoid password spoofing scenarios.
Beta2 also adds new APIs to support inking and stylus input support.
UI Automation and Accessibility
Beta2 adds UI Automation Framework support into Silverlight. UI Automation (or UIA) enables screen readers and other assistive tools to identify and interact with the components that make up your Silverlight 2 application.
Beta2 uses the UIA framework and adds UIA based behaviors to an initial set of Silverlight controls. By the final release of Silverlight 2 all controls will have UIA based behaviors built-in. We will also add support for high-contrast scenarios. These features will enable you to build accessible, section 508 compliant, applications. This UIA support will also enable automated UI testing of applications.
Animation and Graphic System
Beta2 adds support for animating custom dependency properties. Object animation support (animating structs) is also now supported. Beta2 also supports the ability to create Storyboards in code that can animate parts of the render tree without having to be added to it (allowing you to embed animations entirely in code). Per frame animation callback support will be added in the final release.
Beta2 includes a new Visual Tree Helper static class that provides advanced visual tree inspection APIs. It provides features such as the ability to enumerate children of an element and getting the ancestor/parent of a given reference element. These APIs work against any UIElement you pass to it.
Beta2 now supports an XML based manifest file for DeepZoom collections. Beta2 also adds extensible MultiScaleTileSource support for DeepZoom (which allows developers to hook up existing image pyramids that don’t conform with the Deep Zoom format to the high performance rendering of Deep Zoom).
Silverlight Beta2 includes a lot of fixes/changes to improve API compatibility between Silverlight and WPF (note: the final Silverlight release will contain some additional compatibility work as well). We are also adding some new APIs we are introducing in Silverlight 2 to WPF in .NET 3.5 SP1 this summer.
This work, combined with the VSM support we are adding to WPF later this year, will enable good code re-use across browser and desktop applications.
Silverlight 2 Beta2 includes some significant Media related feature work:
Beta2 adds support for "adaptive streaming" - which enables you to encode media at multiple bit-rates and then have a Silverlight application dynamically switch between them depending on the network and CPU conditions.
This enables much richer end-user media experiences - since it makes it possible for content providers to provide both lower-end and higher-end bit rate versions of a video, and then have Silverlight choose the optimal one to use based on an end-user's machine hardware and network capacity. If while watching the video the machine or network conditions change, Silverlight can automatically switch to a more appropriate bit-rate without any buffering or interruption glitch.
Silverlight's support for adaptive streaming is extensible - which enables anyone to plug-in their own logic to control where the media content comes from, and what bit-rate should be used. This means that any CDN or media delivery provider can easily integrate their systems with Silverlight and deliver super high quality video delivery.
Beta2 includes DRM content protection, and supports Windows DRM and PlayReady DRM. Both work cross browser and cross platform.
Server Side Playlists
Beta2 adds support for server side playlists (previous releases only supported client-side playlists).
Silverlight 2 Beta2 includes a bunch of work in the networking space:
Cross Domain Sockets
Beta2 now enables cross domain networking support using both HTTP and Sockets (meaning your application can call sites other than the one the application was downloaded from).
Silverlight will check for the existence of an XML policy file on target servers that indicates whether cross domain network access is allowed. Silverlight supports a new XML policy file format that we've developed, as well as Flash policy files (which means existing sites open to Flash can be called from Silverlight without any additional work).
Background Thread Networking
Beta2 now allows Silverlight applications to initiate network requests on background threads, as well as process/handle network responses on background threads. This enables a bunch of powerful scenarios, and allows you to avoid blocking the browser's UI thread while doing both HTTP and Socket network communication.
Duplex Communication (Server Push)
Beta2 enables support for setting up duplex communication channels with a WCF service on a server. This enables a clean programming model that allows servers to "push" messages to Silverlight clients without the developer having to manually poll servers for changes. This programming model is very useful in a variety of scenarios, including instant messenger/chat applications, and monitoring/update applications like stock tickers and trader applications.
Beta2 enables significantly improved interop with SOAP based web-services. Web service proxy class end-point URLs can now be configured without recompiling applications. Visual Studio also now has a new "Silverlight-enabled WCF Service" project item template that you can add to ASP.NET web projects to publish services to clients.
REST and ADO.NET Data Services
Silverlight includes support for working with REST based web-services.
Beta2 adds support for calling and consuming ADO.NET Data Services (formerly code-named: "Astoria"). ADO.NET Data Services will ship as part of .NET 3.5 SP1 and makes it easy to publish data end-points within an ASP.NET web project that are consumable from any client using REST URIs. Silverlight Beta2 now includes ADO.NET Data Service client support that allows you to easily call these services (and optionally use LINQ expressions within Silverlight to express remote REST queries to them).
Silverlight supports calling JSON-based services on the web.
Beta2 now includes LINQ to JSON support that enables you to easily query, filter, and map JSON results to .NET objects within a Silverlight application. This makes it easy to call and work with existing AJAX end-points and services published on the web.
Silverlight 2 Beta2 includes a bunch of work in the data space:
Beta2 adds a number of new features to the DataGrid control. These include:
- Auto-sizing support for columns and rows
- Column sorting (with both single column and multi-column sort support)
- Column re-ordering support by end-users (allowing them to drag/drop columns to re-arrange the order)
- Frozen column support (allowing you to prevent a particular column from being customized)
- Performance and bug fixes
Beta2 adds more core data-binding features and better validation support. These include:
- Per-binding Validation and BindingValidationError event handler support on controls (allowing you to handle input validation with TwoWay bindings)
- Support for binding expressions on attached properties
- Richer binding value conversion support (including value conversion fallback support)
Silverlight enables applications to store data locally on a client (via a feature we call "Isolated Storage"). Applications can prompt users to grant them size permissions for this storage (for example: a user might grant an email program 50MB of local storage).
Beta2 increases the default local storage space provided to Silverlight applications to 1MB in size. Beta2 also now provides better end-user support for managing per-site storage permissions, as well as the ability to easily revoke/delete an application's local storage. Management UI to control this can now be brought up by an end-user by right-clicking on a Silverlight application and choosing the "Silverlight Configuration" menu option.
Understanding Compatibility with Silverlight 1.0 and Silverlight 2 Beta 1
Silverlight 2 Beta2 is compatible with applications that target Silverlight 1.0.
Silverlight 2 Beta2 will not run applications that target Silverlight 2 Beta1, since we've made a number of API changes between the two betas for the new features being added in Silverlight 2. Browsers that have Silverlight 2 Beta1 installed which visit a site that hosts a Silverlight Beta2 application will be prompted to upgrade to the newer beta of Silverlight. Once they do this they won't be able to run Beta1 applications without uninstalling Beta2. This means that if you have published a running sample on the web built with Beta1 you will probably want to update it to Beta2 soon.
We have published a document that details the changes between Beta1 and Beta2 here that can help with this. I also recommend reading Shawn Wildermuth's What Changed in Silverlight 2 Beta2 and Upgrading your Silverlight 2 Projects to Beta2 posts for more details on some of the changes between Beta1 and Beta2.
To learn more about Silverlight 2 and download the Beta2 release, please visit the http://www.silverlight.net and http://expression.microsoft.com web-sites. We'll be posting articles, tutorials, videos and more on both sites in the days and weeks ahead. I'll also be posting some tutorials of my own here on my blog as well.
If you haven't already read them I'd also recommend checking out Scott Guthrie's First Look at Silverlight 2 and First Look at Expression Blend with Silverlight 2 blog posts that he wrote a few months ago when Beta1 shipped, since they provide a good overview of the Silverlight programming model and how to target it using both Visual Studio 2008 and Expression Blend.