Package Exports
- @polymer/iron-a11y-announcer
- @polymer/iron-a11y-announcer/iron-a11y-announcer.js
This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (@polymer/iron-a11y-announcer) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.
Readme
<iron-a11y-announcer>
iron-a11y-announcer
is a singleton element that is intended to add a11y
to features that require on-demand announcement from screen readers. In
order to make use of the announcer, it is best to request its availability
in the announcing element.
Note: announcements are only audible if you have a screen reader enabled.
See: Documentation, Demo
Usage
Installation
npm install --save @polymer/iron-a11y-announcer
In an html file
<html>
<head>
<script type="module">
import {IronA11yAnnouncer} from '@polymer/iron-a11y-announcer/iron-a11y-announcer.js';
// Initialize the announcer.
IronA11yAnnouncer.requestAvailability();
// Note: announcements are only audible if you have a screen reader enabled.
IronA11yAnnouncer.instance.fire('iron-announce',
{text: 'Hello there!'}, {bubbles: true});
</script>
</head>
</html>
In a Polymer 3 element
import {PolymerElement, html} from '@polymer/polymer';
import {IronA11yAnnouncer} from '@polymer/iron-a11y-announcer/iron-a11y-announcer.js';
class SampleElement extends PolymerElement {
static get template() {
return html`
<button on-click="announce">Announce</button>
`;
}
function attached() {
IronA11yAnnouncer.requestAvailability();
}
// After the `iron-a11y-announcer` has been made available, elements can
// make announces by firing bubbling `iron-announce` events.
// Note: announcements are only audible if you have a screen reader enabled.
function announce() {
IronA11yAnnouncer.instance.fire('iron-announce',
{text: 'Hello there!'}, {bubbles: true});
}
}
customElements.define('sample-element', SampleElement);
Contributing
If you want to send a PR to this element, here are the instructions for running the tests and demo locally:
Installation
git clone https://github.com/PolymerElements/iron-a11y-announcer
cd iron-a11y-announcer
npm install
npm install -g polymer-cli
Running the demo locally
polymer serve --npm
open http://127.0.0.1:<port>/demo/
Running the tests
polymer test --npm
Known Issues
This element doesn't work on Firefox (it doesn't read anything in Voice Over), since
aria-live
has been broken since the Quantum redesign (see the MDN docs demo)
-- we tested it on Firefox 60, but it doesn't look like a regression, so
it's probably broken on older versions as well.