👩‍💻📞 July WinUI Community Call (July 15, 2020)

[anawishnoff]

The call has now ended. Thanks to everyone who tuned in and asked questions!

If you missed the call, you can watch a recording here: https://youtu.be/lcnqqkYggCw
If your question was missed on this month's call, we'll try our best to follow up on Github or answer it in the next call in August :)

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Details

Date: July 15, 2020
Time: 16:00-17:00 UTC (9:00-10:00am Pacific)

Anyone and everyone is welcome - no pre-registration is required.
This will be an informal interactive live stream directly with members of our engineering team.

Format

In this community call we'll be welcoming two guests from related teams here at Microsoft.

At the end of every community call we have a Q&A session where our team answers your questions about all things WinUI.
Ask your questions in the comments of this issue! If any questions come up during the call, you can ask them live in the comments as well.

Agenda

Intro, Updates on WinUI 3
Guest Spotlight: Project Reunion and WinUI
Guest Spotlight: The WPF Roadmap for 2020-2021
Q&A

[StefanKoell]

I have a couple of questions regarding WinUI and WPF:

• will there be a way to pull in individual WinUI controls without applying the style to the whole application? the reason I ask this is, that I am also dependent on 3rd party UI controls (e.g. docking library) and applying styles on a global scope would mess with their styles.
• will render performance be addressed in WPF at some point?
• I understand that there are many PRs already for WPF but there's no real activity in reviewing/merging them. When will the WPF repo finally pick up some traction?

[mdtauk]

@Felix-Dev Look at the Agenda, WPF will be discussed.

Agenda

Intro, Updates on WinUI 3
Guest Spotlight: Project Reunion and WinUI
Guest Spotlight: The future of WPF
Q&A

[Felix-Dev]

@mdtauk Ahahaha, in that case, disregard what I just said here.

Two questions: Are the WinUI and WPF teams working together (for example on WinUI Desktop)? As WinUI is the leading native UI product on Windows, can we expect the WPF team to work on WinUI in the future ( as in bundling development resources behind the leading native UI product)?

[StefanKoell]

I have one more question about WPF (and other platforms/frameworks): will there be native SVG support at some point. This is a de-facto standard and even Xcode 12 has now native SVG support which just works...

[niels9001]

What updates are there, related to:

• Customizing the window: the ability to create borderless (and transparent) windows (Proposal: Borderless transparent window background support in apps using WinUI #1247)
• Acrylic support in 3.0 or 3.1 (Why must background acrylic be discontinued in WinUI 3? That will surely devastate and disappoint many, for obvious reasons #2236)

[pjmlp]

Regarding the future of WPF, what are the transition plans to eventually get us to move into WinUI?

As mentioned on a few other threads, the effect shaders and System.Windows.Media.Media3D is something I care about, specially since they allow for quick 3D visualizations in .NET without having to go down the C++ coding route (regardless how it is being advertised as being plus for WinUI), or to depend on a full blown .NET friendly game engine.

Then another reason to stay with WPF is the tooling available to us via Blend and graphical visualizations.

So whatever the roadmap for WPF might be, if migrating WPF applications to WinUI is part of the plan, it shouldn't be at the expense of losing features and having to rewrite code from scratch with lesser tooling, because that is how you keep people using older stacks.

Now one thing that would be great after all these years, would be some way to finally use INotifyPropertyChanged without property handling boilerplate or relying on external MVVM third party frameworks.

[Bohdan-dotcom]

Will there be any possibility in the next update of the 21H1 function that Windows 10 will be really super efficient in booting the system and shutting down the system as well as in the operation of this system which I would ask for in this update.

[Pinox]

would luv to hear MS opinion on this thread :
microsoft/WindowsAppSDK#105

[LanceMcCarthy]

I think the decision to decouple WinRT from .NET5 was a good idea. By having the C#/WinRT toolchain outside of the .NET5 lifecycle, it should allow us to have .NET5/NS21 support in our UWP-WinRT apps without waiting for the .NET5 team to include support for things.

My main question for Kevin and team are:

• What is the status of C#/WinRT and how does it currently play into UWP-WinRt apps using .NET5/NS21? (in terms of WinUI3 and UWP-WPF apps, it makes sense, but I'm unclear on how this works for UWP-WinRT apps).
• What does such a project structure look like, does it mean setting a MinSDK/TargetSDK and add a NuGet package (ala WinUI2 style)

I completely understand the need to not over-promise something that might not make it in time for release X. A headnod that UWP-WinRT is not on the chopping block (Felix-Dev has a nice post in the thread @Pinox linked to) should be enough for many devs to keep investing in their UWP-WinRT apps (instead of ditching it in favor of a UWP-WPF app).

[mveril]

What is the procedure to create a WinUI3 controls library targeting .NET UWP and .Net Desktop at the same time ?

[Xarlot]

Do you have any timeframe for fixing performance issues with marshaling?

Do you have any plans for better 3d party vendor support? For now, we cant use XAML direct for custom properties, we cant create our own descendants for a lot of controls and mechanisms (for example virtualization) so we cant provide our users better experience than in standard controls.

Do you have any plans to improve the XAML engine?
The lack of type descriptors makes it impossible to define simple things in XAML.
The lack of triggers or the same mechanisms like CSS styles in Avalonia that allow 3d party devs define logic on the style level makes 3d party XAML harder to read, maintain, and customize. The VisualStateManager defines its content in templates so it could not be inherited and overridden by the end-user. End-user forced to copy, paste, and maintain giant templates with custom logic and its dependencies. We struggled with this a lot in the Silverlight era.
3d party vendors need the ability to define custom themes like in WPF, not only predefined fluent.

[michael-hawker]

What is the procedure to create a WinUI3 controls library targeting .NET UWP and .Net Desktop at the same time ?

@mveril this is kind of in limbo right now until WinUI3 UWP supports .NET 5 as otherwise you have to target both .NET 5 and .NET Native for the library to function in both environments.

For now, with the Windows Community Toolkit Preview for WinUI, we decided to just support .NET 5 for the Desktop support banking on .NET 5 support to come eventually for UWP (as then the library should just work).

So, ideally you should just make a WinUI 3 control library and target .NET 5, but if you want something that works with both Desktop and UWP for the current Previews, you'll have to multi-target the library.

[stevenbrix]

So, ideally you should just make a WinUI 3 control library and target .NET 5, but if you want something that works with both Desktop and UWP for the current Previews, you'll have to multi-target the library.

@mveril and to piggy back on what @michael-hawker said, you'll have to use https://github.com/novotnyllc/MSBuildSdkExtras in order to do that with Desktop and UWP in their current state

[AathifMahir]

My question is any plans on making project Reunion as native windows app UI library or It's going to co-exist with all lagacy stuffs.

[StefanKoell]

What about true ARM64 support in WPF? I've read that there are plans for this but more details and a timeline would be interesting.

[jamesmcroft]

Follow up from the last call, will there ever be a time when we see WinUI being a choice for 2D UI in 3D mixed reality experiences on HoloLens or WMR devices?

Also, will WinUI bring better windowing API support for positioning multiple windows of a single 2D app running mixed reality?

[riverar]

Q: Where is the WinUI 3 dev status document shown during the February WinUI Community Call? Developers still have no idea what's truly landing in WinUI 3 and we're inching closer to preview go-live.

[riverar]

Q: What's the current commitment for WPF support? Are we talking about supporting the scenario in which developers can add both WPF and WinUI XAML files to a project and the solution will build? Or will developers have to pick and choose? Or some other scheme?

[terrycox]

Any news on file / folder pickers?

[terrycox]

Can you discuss the level of coordination your team has with the WinRT and .NET5 efforts?

[Symbai]

Q: Will the desktop support for WinUI be a true and native support, completely decoupled from any UWP related stuff? Or will be something like the XAML Island which hosts UWP stuff in our desktop applications and comes with lots of issues and limitations?

Q: Any news about an updated MediaPlayer for desktop applications? For a long time we only had the Windows Media Player as a control. Then we got the very limited and buggy MediaPlayerElement through XAML Island which is quite unsupported, i.e. reported bugs remain unfixed for over a year now.

[terrycox]

For Eve: How do the WinRT Projection packages fit into Project Reunion?

[ranjeshj]

• will there be a way to pull in individual WinUI controls without applying the style to the whole application? the reason I ask this is, that I am also dependent on 3rd party UI controls (e.g. docking library) and applying styles on a global scope would mess with their styles.

@StefanKoell could you open an issue so we can track this need. Thanks