Announcing: WinUI 3 - Windows App SDK 0.8! 🎉✨

We’ve just shipped the latest stable version of WinUI 3, which is a part of Windows App SDK v0.8! This release includes lots of bug fixes and stability improvements. This version of WinUI 3 can be used for shipping production apps to the Microsoft Store.

Shipping WinUI 3 as a part of the Windows App SDK

In order to use this version of WinUI 3, you’ll download the Project Reunion Visual Studio Extension (VSIX) to get started. The Project Reunion VSIX includes WinUI Project Templates that you’ll use to build your WinUI 3 app, as well as access to other Windows App SDK components. The Windows App SDK package includes a reference to the WinUI 3 NuGet package.

For more on the Windows App SDK, see their documentation and repository. For installation instructions, see Set up your development environment.

NOTE: The Windows App SDK was previously known by the code name Project Reunion. Some SDK assets such as the VSIX extension and NuGet packages still use the code name, but these assets will be renamed in a future release. Some areas of this doc still use Project Reunion when referring to an existing asset or a specified earlier release.

What’s new

These are all of the new changes in WinUI 3 since the release of Project Reunion 0.5.

• The Pivot control has been added back in and can now be used in any WinUI 3 app.

• All bug fixes from Project Reunion v0.5.5, v0.5.6, and v0.5.7 are included with this release.

• The ColorHelper.ToDisplayName API is no longer available.

• The following types have been removed:

  • Microsoft.Graphics.IGeometrySource2D
  • Microsoft.Graphics.IGeometrySource2DInterop

  Please use Windows.Graphics.IGeometrySource2D and Windows.Graphics.IGeometrySource2DInterop instead.

• All types in the Microsoft.System namespace have been moved to the Microsoft.UI.Dispatching namespace, including the DispatcherQueue class.

• The AcrylicBrush.BackgroundSource property has been removed, since HostBackdrop is not supported as a BackgroundSource in WinUI 3.

Bug fixes

This is the list of all bugs fixed in WinUI 3 since Project Reunion 0.5.

• Fix tooltip to get the current pointer position rather than using the last seen pointer ID

• #4197

• Crash in shadows code when device goes on low-battery

• #3001

• #3658

• Crash in RichEditBox when copying/pasting/changing text style

• #4536

• #923 - Building class library with XAML controls in Release config fails

• #4179

• Hide windowed popups when the top-level window (or island) moves

• StandardUICommand page in WinUI 3 Controls Gallery not showing everything

• #4804

• Context menu displayed at the wrong location for EditableComboBox

• Changing RichTextBlock Selection with touch makes selection indicator go away

• #4806

• WinUI 3 error message needs rewording: “Cannot resolve ‘Windows.metadata’. Please install the Windows Software Development Kit. The Windows SDK is installed with Visual Studio.”

• #1048

• Move focus off the WebView2 (if necessary) when browser process crashes

• #3694

• PointerReplay constantly running

• #4499

• AutoSuggestBox, ComboBox, and CommandBarFlyout aren’t setting ShouldConstrainToRootBounds=“false” on their popup

• #4510

• WebView2 initial tab focus lost

• WebView2 crashes when DPI changes after Close()

• #4197

• SwapChainPanel has a white line border in dark mode

• Crash in tooltip when hovering between different items with tooltips too quickly

• Border areas around WebView2 appear to be transparent or show a color

• Unable to stop app exit using closed event handle

Experimental Features

This release does not include experimental features. If you’d like to continue using experimental features in your app, feel free to continue using the latest Project Reunion 0.8 Preview.

Known Issues

For a list of all the known issues for the Windows App SDK 0.8, please see the Windows App SDK release notes.

Getting started

First, you’ll need to set up your dev environment with the appropriate technologies. See our documentation for installation instructions and more information on project types:

Install the Windows App SDK

Create WinUI 3 Projects

While you’re developing, check out the API Reference documentation.

Take a look at our walk-through docs:

• Get started developing apps with WinUI 3
• Build a basic WinUI 3 app for desktop

You can also update your existing WinUI 3 app to use the new Windows App SDK 0.8 release using these instructions: Update existing projects to the latest release of the Windows App SDK.

We love feedback! We encourage you to file any bug, big or small, on our repo using this template. Knowing which issues and features are important and/or critical to our customers highly influences which ones we tackle. Even though we ship with the Windows App SDK, please continue to file WinUI-specific bugs on this repo.

Using WinUI 3 - Windows App SDK 0.8 with our ecosystem partners

This latest release is in the process of being integrated into several other important ecosystem technologies. To test out and follow that progress, check out some of our partner technologies below:

• Actipro Software is migrating their vast UI control offerings over to WinUI 3, including their SyntaxEditor code editor, propertygrid, native type edit boxes, docking/MDI, charts, and more.

• DevExpress: DevExpress has released 20 new WinUI controls with Windows App SDK 0.8 support, including the Data Grid, Scheduler, Charts, Ribbon Toolbar, and more. All 20 UI components are available free-of-charge.

• Esri: ArcGIS Runtime SDK for .NET adds mapping, spatial analytics, and location intelligence capabilities to your apps on Android, iOS, and Windows. Support for WinUI 3 is now available.

• GrapeCity plans to bring their popular desktop UI controls to WinUI later this year! Learn more about their data connection service components for WinUI.

• Infragistics: Ultimate UI for WinUI brings business critical, high performing, and feature rich line of business controls to your apps that target any platform that runs Windows (including Windows on ARM64).

• Syncfusion: Updated their projects to Microsoft.ProjectReunion from Microsoft.WinUI following upgrade instructions. All their controls are working fine.

• Telerik UI for WinUI: the market first UI controls suite for crafting Win32 and UWP apps with WinUI 3, comes with feature-rich controls like Ribbon, DataGrid, Charts, Gauges, Barcode, and more.

• Uno Platform: Use WinUI 3 – Windows App SDK 0.8, XAML and C# to build pixel-perfect, single-codebase, native applications that can run on Web, Desktop and Mobile. It is free, open-source and available today.

• Windows Community Toolkit (Microsoft): The WCT is currently working on supporting Reunion 0.8 release candidate. It provides tons of new controls and capabilities for use in your WinUI app. You can check out their open source repo here.

What’s next

To keep up with progress being made on WinUI 3, please see our feature roadmap which gets updated regularly. We also give monthly updates on our WinUI Community Calls, where you can directly ask the team any questions you have.

---

Update #1 - Windows App SDK 0.8.1 is now available

Windows App SDK 0.8.1 is a stable servicing release that fixes a few critical bugs.

Bugs fixed in Windows App SDK 0.8.1:

• Windows App SDK cannot run on latest Insider build
• Crash in editable ComboBox when entering a value that does not appear in dropdown
• WebView2 doesn’t allow user to tab out once focused has been received
• Fully qualify Windows.Foundation.Metadata.DefaultOverload namespace in WinUI generated code to avoid namespace ambiguity
  • This fixes bug #5108.
• Security fix – see CVE-2021-34489 for more details.

The limitations and known issues for v0.8 also apply to v0.8.1, unless marked otherwise in our documentation.

---

Update #2 - Windows App SDK 0.8.2 is now available

Windows App SDK 0.8.2 is a stable servicing release that a couple more critical bugs for 0.8.0.

Bugs fixed in Windows App SDK 0.8.2:

• Windows App SDK and WinUI 3 are now supported in Visual Studio 2022 Preview 2 and above.
• For .NET apps, you may receive the following error when passing in an array of enums: Object contains non-primitive or non-blittable data.
• Writing using the HandWriting Panel inside a textbox causes a crash
• Icons/images always load at their 100% scale value rather than based on the monitor scale value
• Garbage collection of EventSource<T> causes subsequent failure to unsubscribe handlers (see GitHub issue for more details)
• Security fix – see CVE-2021-34533 for more details.
• SwapChainPanel.CompositionScaleChanged sometimes returning incorrect CompositionScale values after changing display scale

The limitations and known issues for v0.8 also apply to v0.8.2, unless marked otherwise in our documentation.

[thomasclaudiushuber]

Congrats on getting this out.

Windows App SDK, I like it, it is what it is, this name is sooo much clearer and better than Project Reunion.

[codendone]

@asklar #include <microsoft.ui.dispatching.co_await.h> to get the resume_foreground functionality.