Focus menu items with aria-activedescendant#43
Conversation
Leave DOM focus on the summary that opened the menu or a filter input inside the menu. Navigating items with arrow keys should not move focus away from the input field.
A menu with a filtering input at the top cannot itself be role=menu
because it hides the input from screen readers. The following
relationship is required.
<details-menu role="none">
<input>
<div role="menu" aria-activedescendant="i1">
<button id="i1" role="menuitem></button>
</div>
</details-menu>
Managing focus with aria-activedescendant requires the attribute to be
attached to the role=menu element in order for the focused item to be
announced.
| fromEvent(details, 'change', e => shouldCommit(details, this, e)), | ||
| fromEvent(details, 'keydown', e => keydown(details, this, e)), | ||
| fromEvent(details, 'toggle', () => clearFocus(details, this)), | ||
| fromEvent(details, 'toggle', () => identifyItems(this), {once: true}), |
There was a problem hiding this comment.
Does this mean runtime mutations of the HTML will break focussing?
muan
left a comment
There was a problem hiding this comment.
When we discussed this approach, I wasn't sure how it would work, because according to the spec:
Instead of moving DOM focus among descendant elements, authors MAY set DOM focus on an element that supports
aria-activedescendantand then usearia-activedescendantto refer to the element that is active.Authors MUST ensure that one of the following two sets of conditions is met when setting the value of
aria-activedescendanton an element with DOM focus:
...
It suggests that aria-activedescendant would be set on an element that's receiving DOM focus, which was why in #38 it was set on the input.
It seems like this implementation does work with VoiceOver. However, in NVDA it reads out the focused input's text instead:
NVDA requires the element with DOM focus to manage the active descendant. We use summary or an optional input field as the focused element. Co-authored-by: Mu-An Chiou <[email protected]>
Co-authored-by: Mu-An Chiou <[email protected]>
Replaces the DOM focusing of menu items with
aria-activedescendant. This allows menus to contain other focusable elements, like<input>, that don't lose focus while navigating menu items with arrow keys.A menu with a filtering input at the top cannot itself be
role=menubecause it hides the input from screen readers. The following relationship is required.Managing focus with
aria-activedescendantrequires the attribute to be attached to therole=menuelement in order for the focused item to be announced.This is similar to #38 but differs in that there remains only one method of focusing menu items and the menu is unaware of its contents, which may or may not include an
<input>field.