Silverlight 4 Formally Launched

Microsoft releases shipping version of Silverlight 4 with a focus on ease and speed of development

Microsoft's Scott Guthrie today formally launched the shipping version of Silverlight 4, noting that the new platform enables developers to "build great applications for the business as well as applications that run outside the desktop."

Though announced today, the final Silverlight 4 bits and the Visual Studio 2010 tooling that goes with it will be available for download two days from now, Thursday, April 15, according to Guthrie, corporate vice president, .NET Developer Platform.

Guthrie focused on three types of applications: Media-centric applications and experiences, business-oriented applications, and desktop-based applications. Little new was announced at the event--Silverlight 4 has been in public beta since Microsoft's Professional Developer Conference (PDC) in November--but a series of demos showed off the platform's extensive capabilities.

Demos included an Orbitz app that combines data from two disparate sources to feed a CRM application, as well as a Sports Illustrated app that provides interactive, visual display of cover image content using the Deep Zoom functionality in Silverlight.

Guthrie also discussed Silverlight tooling, inviting well-known Silverlight developer John Papa to give a demo showing how to build an online book store in Visual Studio 2010 using Silverlight 4 and .NET RIA Services.

Guthrie stressed that Visual Studio 2010 provides a rich development experience for Silverlight, including WYSIWYG designers for controls, style and layout, as well as sophisticated data binding controls. Full intelliSense and debugging capability is offered in the IDE as well, Guthrie said. Guthrie also emphasized the project sharing capability of the two tools, which are both included in MSDN Premium subscriptions.

Ward Bell, vice president of technology at IdeaBlade, showed off one of the touted features of Visual Studio 2010, the IntelliTrace historical debugger. The demo showed how IntelliTrace records Silverlight 4 application activity and produces a visual depiction of activity for debugging purposes.

Sandboxing also got a lengthy look. Guthrie called out new windowing APIs, notification pop-up support, HTML hosting support, and drag-and-drop target support that allows users to drag objects from the desktop into the Silverlight application. Trusted application support was also emphasized. Silverlight 4 provides cross-site network support, local file system capability and custom window chrome capability to enable trusted apps.

Dave Wolf, vice president of strategy at Cynergy, demoed an application his company built for eBay, called the eBay Simple Lister, that showed off the out-of-browser capability of Silverlight 4. In the demo, Wolff illustrated Silverlight 4's webcam integration, snapping a shot of a product bar code, which the app then used to retrieve item information from eBay's servers.

The Cynergy demo also highlighted the expanded capabilities of Expression Blend 4. Wolff showed how data binding can be easily wired up directly within Blend, without requiring the intervention of a Visual Studio developer. He also delved into the control handling and animation capabilities of Blend.

"Pretty nice, huh? Template data bound to a list box and animated right in," Wolf concluded.

Guthrie concluded by plugging Silverlight 4's improved performance, with a just-in-time runtime that promises to double performance, 30 percent faster startup, and improved profiling support for app optimization.

Silverlight's reach continues to expand. At PDC, Microsoft said Silverlight was installed on 45 percent of Internet-connected devices. That figure is now approaching 60 percent, Guthrie said.

About the Author

Michael Desmond is the founding editor of Redmond Developer News. Contact him at [email protected].

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