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OpenSilver 3.1 Unveils Drag-and-Drop XAML Designer for VS Code

Claiming an industry first, Userware announced a drag-and-drop XAML designer for use in Visual Studio Code, coming with OpenSilver 3.1, the latest iteration of the open-source implementation of Microsoft's long-deprecated and oft-mourned rich client development platform, Silverlight.

OpenSilver 1.0 arrived in 2021 just as Microsoft ended support for Silverlight, a browser plug-in primarily used to create Rich Internet Applications, providing functionality similar to Adobe Flash such as playing music, videos, animations and so on.

The Paris-based Userware today (Dec. 10) announced version 3.1, with the highlight being the XAML designer, previously available only in Microsoft's full-fledged Visual Studio IDE.

"Until now, XAML UI design was largely limited to Visual Studio on Windows, leaving developers on macOS and Linux without visual design tools," the company said. "OpenSilver 3.1 changes that by introducing a fully cross-platform designer, enabling developers to create complex user interfaces visually in VS Code -- on any operating system."

While the designer comes in a downloadable SDK .vsix file for use in VS Code, the company also published it online for users to try out immediately, shown here:

Online XAML Designer
[Click on image for larger view.] Online XAML Designer (source: Userware).

Other highlights of the release noted by the company include:

  • Enhanced "WPF Everywhere" support: New features include:
    • DynamicResource
    • MultiBinding
    • x:Static
    • UniformGrid
  • Support for .NET 9: Support in the brand-new .NET 9 helps OpenSilver applications helps applications run natively in modern browsers using WebAssembly and HTML5, with no need for plugins or additional installations.
  • Modern UI theme: This is inspired by Material and Fluent Design principles, offering a flat aesthetic with light and dark modes for contemporary web applications. The theme supports easy customization via the XAML designer, enabling quick color palette adjustments for branding. The default splash screen has also been updated. For legacy applications, the original Silverlight theme is still available to ensure seamless, pixel-perfect migrations.
  • Going forward, the company said, future updates include:

    • Full WPF compatibility: Expanding support for triggers, advanced styles, and more.
    • MAUI Hybrid integration: Combine native and web technologies to build cross-platform apps for Windows, macOS, iOS, and Android.
    • Blazor interoperability: Mix and match Blazor components with XAML in the same project.
    • 3D UI support: Early previews of this feature are already available at XRSharp.io

    About the Author

    David Ramel is an editor and writer at Converge 360.

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