Should radio buttons activate with Enter key when focused?

[ckundo]

With regards to https://www.w3.org/WAI/ARIA/apg/patterns/radio/examples/radio/, currently the Enter key activates the control with initial focus. Per the whatwg spec on implicit submission, Enter key should submit a form. It's confusing then, and maybe incorrect, to capture Enter keypress to activate the radio button.

For what it's worth, the default behavior in with native radio buttons -- Chrome at least -- is to only activate on Space, whereas Enter does submit. See https://codepen.io/ckundo-the-styleful/pen/YzMwPPY

[css-meeting-bot]

The ARIA Authoring Practices (APG) Task Force just discussed Should radio buttons activate with Enter?.

The full IRC log of that discussion

<jugglinmike> Topic: Should radio buttons activate with Enter?
<jugglinmike> github: https://github.com//issues/2954
<jugglinmike> Matt_King: I think this is an important question, partly because we used to have checkboxes which activated on "enter", and somebody pointed out almost this identical issue
<jugglinmike> Matt_King: e.g. how do they behave natively, etc.
<jugglinmike> Matt_King: We changed the checkbox so that it only activates on "space"
<jugglinmike> Matt_King: I'm interested in answering this question as soon as possible because at this moment in time, the "radio button" test plan is being revised in ARIA-AT
<dmontalvo> q+e
<jugglinmike> Matt_King: ...if we're going to take the "enter" key away from this, I'd like to remove the associated test now rather than have to update the ARIA-AT test plan again later
<jugglinmike> jongund: I'm okay with "spacebar" alone activating the radio
<jugglinmike> Matt_King: In Chrome, Cameron is saying that only the space bar activates native radio buttons
<jugglinmike> Matt_King: Should we look at what native radio buttons do in at least Safari?
<jugglinmike> Matt_King: Between Chrome and Safari, should we consider that "alignment"? Should we also consider Firefox?
<jugglinmike> Matt_King: Our pattern is already different from native radio buttons because in native radio buttons, "forward tab" and "backward tab" are not symmetrical operations. We've discussed this previously
<jugglinmike> Matt_King: The browsers don't treat it like a true composite the way that ARIA says it should be a true composite
<dmontalvo> q-
<jugglinmike> Matt_King: If you tab into the radio group, tab out of it, and then tab back into it, you don't end up in the same place
<jugglinmike> jongund: "Enter" submits the form in native radio buttons in Safari
<jugglinmike> jugglinmike: Is it worth checking what "enter" does on a radio button that isn't part of a form?
<jugglinmike> Matt_King: Yeah, probably. I'd hope it would be a "no-op" in that case, but we should check
<jugglinmike> jongund: In Safari, the "enter" key does nothing if there's no "form" element. The space bar still toggles in that case
<jugglinmike> Matt_King: I think the fact that there is two major browsers is compelling. I also think that consistency with checkbox is relevant
<jugglinmike> jongund: I don't think we should deviate from what browsers do if we don't have a good reason (e.g. like we have a good reason to deviate when it comes to "tab")
<jugglinmike> CurtBellew: I agree with this--"space bar" activates and "enter" does not
<jugglinmike> s/still toggles/still activates/
<jugglinmike> Matt_King: If we are going to fix this, it requires a change to the code and the documentation. I'm happy to take on the editorial change in the pattern
<jugglinmike> Matt_King: Do we have any takers who would like to modify the example?
<jugglinmike> jongund: I can do that
<jugglinmike> Matt_King: We have two "radio" examples: one with active descendant and one with roving tab index
<jugglinmike> jongund: Just removing support for the "enter" key, right?
<jugglinmike> Matt_King: That's right. You can change both examples in the pull request, and I'll add the documentation changes to your patch
<jugglinmike> jongund: Do we consider this a bug fix?
<jugglinmike> Matt_King: I think this is a material change to guidance. I'm going to label it an enhancement
<jugglinmike> Matt_King: Is it really an enhancement, though?
<jugglinmike> jugglinmike: I think it comes down to whether the prior behavior was intentional. It seems like supporting "enter" was indeed intentional, and that would make this change an enhancement rather than a bug fix
<jugglinmike> Matt_King: I agree
<jugglinmike> Matt_King: I'm assigning myself and jongund

[mcking65]

@ckundo, thank you for observing this inconsistency between the example and the pattern and calling it to our attention.

Pull request #2964 removed Enter key handling for checking the radio. It will be live in production on April 9.