Proposal: Integrate XAML Behaviors to WinUI & WPF

[michael-hawker]

Proposal: Integrate XAML Behaviors to WinUI & WPF

Summary

The XAML Behaviors have been a relative staple for XAML development for a long time now having IDE support in Blend and working for both WPF and UWP directly with minimal changes (besides namespaces). Since they provide common patterns/interfaces for others to build upon, it could be handy to have these integrated into the platform directly. Especially now with WinUI going open source.

See the XAML Behavior discussion on this topic here and a corresponding WPF request similar to this one here.

Rationale

• Would be easier to manage and integrate more directly into the XAML platform if coordinated by the platform team. E.g. Styles, Verbosity, etc...
• Would be easier for other library creators to create components which interact with behaviors or actions without extra dependencies.

Open Questions

• Would this make it easier to maintain by having the C++ version able to be projected to C# as well vs. the split approach now? Maybe that's done more for easier maintenance with WPF <-> UWP C#?

[Panda-Sharp]

Up :)

[GuildOfCalamity]

Are there still plans to integrate this into Microsoft.UI.Xaml?
This should not have to be added as an additional NuGet to projects, as the functionality is sorely lacking in the base classes.