ElementInternals: ariaExpanded property
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since October 2023.
The ariaExpanded property of the ElementInternals interface reflects the value of the aria-expanded attribute, which indicates whether a grouping element owned or controlled by this element is expanded or collapsed.
Note:
Setting aria attributes on ElementInternals allows default semantics to be defined on a custom element. These may be overwritten by author-defined attributes, but ensure that default semantics are retained should the author delete those attributes, or fail to add them at all. For more information see the Accessibility Object Model explainer.
Value
A string with one of the following values:
"true"-
The grouping element this element owns or controls is expanded.
"false"-
The grouping element this element owns or controls is collapsed.
"undefined"-
The element does not own or control a grouping element that is expandable.
Examples
In this example the value of ariaExpanded is set to "true".
class CustomControl extends HTMLElement {
constructor() {
super();
this.internals_ = this.attachInternals();
this.internals_.ariaInvalid = "true";
}
// …
}
Specifications
| Specification |
|---|
| Accessible Rich Internet Applications (WAI-ARIA) # dom-ariamixin-ariaexpanded |