Senior Front-End Engineer and international public speaker at Deque Systems working on accessibility tools with axe-core. O'Reilly Web Platform Award Winner, occasional Angular team member, bike aficionado.
showing 14 lessons...
Learn the basics of web accessibility testing using the keyboard, Web Developer Toolbar, aXe Firefox extension, and Lea Verou's Contrast Ratio tool. We'll look at how to get an overview of a webpage's accessibility, with special attention paid to solving color contrast issues.
For more on accessibility auditing, check out this article: https://marcysutton.com/how-i-audit-a-website-for-accessibility/
For more details on creating accessible dialog content, check out this great article by Marco Zehe, Advanced ARIA Tip #2: Accessible Modal Dialogs: https://www.marcozehe.de/2015/02/05/advanced-aria-tip-2-accessible-modal-dialogs/
NVDA is a popular open source screen reader on Windows that works well with Firefox. It's similar to JAWS, another popular Windows screen reader that works best with IE. But NVDA has no licensing fee plus an open bug tracker, making it great for users as well as developer testing.
In this lesson, you'll learn how to browse a webpage using NVDA's keyboard shortcuts, including headings navigation, skip links, and the Elements List. You'll also learn a bit about Forms Mode and how it impacts screen reader navigation. For more tips, check out the resources below.
If you're on a Windows machine, you can install NVDA directly. If you're on a Mac or Linux, you could install a Windows virtual machine:
Did you know every Mac comes with a fantastic screen reader built-in? Learn the basics for operating Voiceover with Safari, including common key commands, the web rotor, and the help menu. We'll also set up keyboard tabbing in Safari and OSX's System Preferences, two requirements for accessibility testing that occasionally trip up users. In a future lesson, we'll compare Voiceover to Windows screen readers, since they work quite differently.
There are many techniques for hiding content in user interfaces, and not all are created equal! Learn how different hiding techniques in HTML, CSS and ARIA impact keyboard and screen reader users in addition to visual display. As a bonus, we'll also take a look using a screen reader on a mobile device.
What is this thing called ARIA? In this lesson, you'll learn about about WAI-ARIA, a.k.a. Accessible Rich Internet Applications, the W3C spec for specifying accessibility information in HTML and SVG. I cover the basics of applying ARIA roles, states and properties, helpful information for creators of user-interface widgets and component libraries. But it's important to note that you might not need ARIA at all! Before using it, it's important to educate yourself on what ARIA does and doesn't do for you.
Coding for accessibility? You should get familiar with the accessibility tree, a structure produced by platform Accessibility APIs running parallel to the DOM, which exposes accessibility information to assistive technologies such as screen readers. There are multiple tools for visualizing this tree; in this lesson we'll look at Chrome and Microsoft Edge. For more on Accessibility APIs, refer to this amazing article by Leonie Watson. For a how-to on setting up the Chrome Accessibility Inspector, visit bit.ly/chrome-a11y.
Are you building a website or web application that takes user input? Then it's important for you to watch this demo. Learn how to create more accessible forms using basic HTML form labels, fieldsets and legends. You'll even learn a bit about what makes Safari's developer tools pretty awesome.