As a blind screen reader user, and in my career educating designers, developers, and testers on accessibility issues, I have had the opportunity to observe the techniques used by various users to understand the layout and operation of web pages and applications. I have also seen well-intentioned sighted testers believe that components or entire sites are not accessible because they were unfamiliar with the techniques of navigating the web without sight.
In this article, I will walk you through the ways a blind screen reader user can navigate a web page, gather information about its layout and organization, and use that knowledge to efficiently and rapidly navigate a site or application. I hope to convey the importance of using techniques other than the TAB key as a primary means of navigating a website and illustrate the power you provide to a screen reader user by following semantic HTML markup and the principles of the Web Content Accessibility Guidelines.
tabindexof the focused element to “0” ensures that if the user tabs away from the widget and then returns, the selected item within the group retains focus. Note that updating the
tabindexto “0” requires also updating the previously selected item to
tabindex="-1". This technique involves programmatically moving focus in response to key events and updating the
tabindexto reflect the currently focused item. To do this:
Bind a key down handler to each element in the group, and when an arrow key is used to move to another element:
- programmatically apply focus to the new element,
- update the
tabindexof the focused element to “0”, and
- update the
tabindexof the previously focused element to “-1”.
Here’s an example of a WAI-ARIA tree view using this technique.
For a more visual explanation, see the following video by Rob Dodson: