With this package you can broadcast aria-live messages to assistive technology from anywhere in your React applications.
ARIA Live Regions are used to communicate important information to screen reader software.
In web applications we make a lot of changes to our pages using JavaScript. These changes can be completely undetected by screen readers, meaning that not all our users are being notified of important changes to our applications.
A very common example in web applications, is the use of routing software. We need to tell screen readers that a new route has been loaded, as this is usually not automatically detected.
Other examples are error situations, or content and state changes in our application that could be very clear visually but not detected by screen readers.
Using react-aria-live you can broadcast these important messages easily from any component in your application.
The technical double announcer region implementation of react-aria-live was inspired by ngA11y.
npm install react-aria-live
or
yarn add react-aria-live
The library exports two components, namely LiveAnnouncer and LiveMessage.
Wrap your React application in the LiveAnnouncer component. It will render a visually hidden message area in your application that can broadcast aria-live messages. LiveAnnouncer is best placed as high up as possible in your component tree, as ARIA Live Regions are sensitive to changes to the HTML rendering these regions. Best results are obtained when the HTML is rendered only once when the application root component is mounted.
Now you can use the LiveMessage component to send polite or assertive messages. Messages are only triggered when the bound message prop changes.
import React, { Component } from 'react';
import { LiveAnnouncer, LiveMessage } from 'react-aria-live';
class MyApp extends Component {
state = {
a11yMessage: '',
};
render() {
return (
<LiveAnnouncer>
<LiveMessage message={this.state.a11yMessage} aria-live="polite" />
<button
onClick={() => {
this.setState({ a11yMessage: 'Button Pressed' });
}}>
Press me
</button>
</LiveAnnouncer>
);
}
}
export default MyApp;
The LiveMessage component does not have to exist in the same component as LiveAnnouncer, as long as it exists inside a component tree wrapped by LiveAnnouncer.