When should the window be created hidden?

[marc2332]

Hey!

While I was working on accessibility support for Freya I noticed a weird behavior. The initial redraw request event never happens. So after some digging, I found out it only occurs when creating the Winit adapter

I have only tested this on Windows 11.

When creating the Winit adapter:

When not creating it :

I made a little reproduction example, the important line is this one

This issue is easy to fix by simply listening to the Init event of the eventloop and forcing a redraw request:

 Event::NewEvents(StartCause::Init) => {
    window.request_redraw();
}

But, is still not the expected behavior and I wonder if it could be causing other problems I am not aware of.

Anyway, nice job with accesskit 👏

[mwcampbell]

Thanks for the report. Can you please specify which platform(s) this is happening on?

[marc2332]

Thanks for the report. Can you please specify which platform(s) this is happening on?

I have only tested this in Windows 11, I can try in Linux if you want, but not MacOS as I don't have a Mac 😄

[mwcampbell]

You need to create the window invisible, then create the adapter, then show the window. I'm sorry I didn't make that clear in the accesskit_winit docs. This is crucial on Windows, and possibly important on macOS as well.

[marc2332]

You need to create the window invisible, then create the adapter, then show the window. I'm sorry I didn't make that clear in the accesskit_winit docs. This is crucial on Windows, and possibly important on macOS as well.

Ohh, I will try that, Linux works btw 😄

[DataTriny]

Maybe we should panic if Window::is_visible() == Some(true) when initializing the adapter.

[marc2332]

You need to create the window invisible, then create the adapter, then show the window. I'm sorry I didn't make that clear in the accesskit_winit docs. This is crucial on Windows, and possibly important on macOS as well.

Yeah, that works ! ✨ You can close this issue if you want now 😄 But, maybe it could be clarified in the docs/examples.

[DataTriny]

Coming back to this, when exactly is it necessary to create the window hidden so that AccessKit can initialize properly?

• accesskit_macos/Adapter
• accesskit_macos/SubclassingAdapter
• accesskit_unix/Adapter: N/A
• accesskit_windows/Adapter: our example does it, but if I add WS_VISIBLE and remove the call to ShowWindow it seem to work without issues (tested with NVDA and Narrator on Windows 10). Can it be a timing issue under specific circumstances? If no, then we should document that UiaInitMarker must be created when handling WM_NCCREATE.
• accesskit_windows/SubclassingAdapter: window must be hidden.

Once the above items are resolved, we should add a platform-specific note to accesskit_winit::Adapter::new.

[DataTriny]

Solved by #278