Where dynamic content is updated either automatically or in response to a user action, make sure that users are notified of this update in an accessible way.
Make sure that the notification is appropriate to the type and importance of update that has taken place. For example, an update that reports an error or a problem may be considered more important than an update to a newsfeed that is shown as supplementary content to the main page.
- Identify content that may be updated as a WAI-ARIA live region. Use the aria-live attribute on the container of the content that may be updated or, in special cases, use one of the WAI-ARIA special live region roles.
- Make users aware of important changes in content. However, do so by clearly identifying critical updates versus information-only updates. Change focus only when an alert is critical to the user's current activity. Otherwise, don't force a focus change and/or interrupt the user's work. This guideline is especially useful to screen reader users and to those with cognitive disabilities.
- Provide a suitable priority for update notifications. Decide how important it is that a user hears the updated content and whether the screen reader should be interrupted from what it’s currently reading. This will influence what value you give the aria-live attribute.
- For each piece of dynamically updated content, inspect the underlying code. Is it identified in code as a live region, with a suitable level of priority of notification?
- Listen to the page with a screen reader. Are notifications made in an accessible way, including making users aware of important changes in content?