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| 8 | Coding Towards Accessibility | “Can we make it AAA-compliant?” – does this question strike fear into your heart? Maybe for no other reason than because you will soon have to wade through the impenetrable WCAG documentation once again, to find out exactly what AAA-compliant means? I’m not here to talk about that. The Web Content Accessibility Guidelines are a comprehensive and peer-reviewed resource which we’re lucky to have at our fingertips. But they are also a pig to read, and they may have contributed to the sense of mystery and dread with which some developers associate the word accessibility. This Christmas, I want to share with you some thoughts and some practical tips for building accessible interfaces which you can start using today, without having to do a ton of reading or changing your tools and workflow. But first, let’s clear up a couple of misconceptions. Dreary, flat experiences I recently built a front-end framework for the Post Office. This was a great gig for a developer, but when I found out about my client’s stringent accessibility requirements I was concerned that I’d have to scale back what was quite a complex set of visual designs. Sites like Jakob Neilsen’s old workhorse useit.com and even the pioneering GOV.UK may have to shoulder some of the blame for this. They put a premium on usability and accessibility over visual flourish. (Although, in fairness to Mr Neilsen, his new site nngroup.com is really quite a snazzy affair, comparatively.) Of course, there are other reasons for these sites’ aesthetics — and it’s not because of the limitations of the form. You can make an accessible site look as glossy or as plain as you want it to look. It’s always our own ingenuity and attention to detail that are going to be the limiting factors. Synecdoche We must always guard against the tendency to assume that catering to screen readers means we have the whole accessibility ballgame covered. There’s so much more to accessibility than assistive technology, as you know. And within the field of assistive technology there are plenty of other devices for us to consider. Planning to accommodate all these users and devices can be daunting. When I first started working in this field I thought that the breadth of technology was prohibitive. I didn’t even know what a screen reader looked like. (I assumed they were big and heavy, perhaps like an old typewriter, and certainly they would be expensive and difficult to fathom.) This is nonsense, of course. Screen reader emulators are readily available as browser extensions and can be activated in seconds. Chromevox and Fangs are both excellent and you should download one or the other right now. But the really good news is that you can emulate many other types of assistive technology without downloading a byte. And this is where we move from misconceptions into some (hopefully) useful advice. The mouse trap The simplest and most effective way to improve your abilities as a developer of accessible interfaces is to unplug your mouse. Keyboard operation has its own WCAG chapter, because most users of assistive technology are navigating the web using only their keyboards. You can go some way towards putting yourself into their shoes so easily — just by ditching a peripheral. Learning this was a lightbulb moment for me. When I build interfaces I am constantly flicking between code and the browser, testing or viewing the changes I have made. Now, instead of checking a new element once, I check it twice: once with my mouse and then again without. Don’t just :hover The reality is that when you first start doing this you can find your site becomes unusable straightaway. It’s easy to lose track of which element is in focus as you hit the tab key repeatedly. One of the easiest changes you can make to your coding practice is to add :focus and :active pseudo-classes to every hover state that you write. I’m still amazed at how many sites fail to provide a decent focus state for links (and despite previous 24 ways authors in 2007 and 2009 writing on this same issue!). You may find that in some cases it makes sense to have something other than, or in addition to, the hover state on focus, but start with the hover state that your designer has taken the time to provide you with. It’s a tiny change and there is no downside. So instead of this: .my-cool-link:hover { background-color: MistyRose ; } …try writing this: .my-cool-link:hover, .my-cool-link:focus, .my-cool-link:active { background-color: MistyRose ; } I’ve toyed with the idea of making a Sass mixin to take care of this for me, but I haven’t yet. I worry that people reading my code won’t see that I’m explicitly defining my focus and active states so I take the hit and write my hover rules out longhand. JavaScript can play, too This was another revelation for me. Keyboard-only navigation doesn’t necessitate a JavaScript-free experience, and up-to-date screen readers can execute JavaScript. So we’re able to create complex JavaScript-driven interfaces which all users can interact with. Some of the hard work has already been done for us. First, there are already conventions around keyboard-driven interfaces. Think about the last time you viewed a photo album on Facebook. You can use the arrow keys to switch between photos, and the escape key closes whichever lightbox-y UI thing Facebook is showing its photos in this week. Arrow keys (up/down as well as left/right) for progression through content; Escape to back out of something; Enter or space bar to indicate a positive intention — these are established keyboard conventions which we can apply to our interfaces to improve their accessiblity. Of course, by doing so we are improving our interfaces in general, giving all users the option to switch between keyboard and mouse actions as and when it suits them. Second, this guy wants to help you out. Hans Hillen is a developer who has done a great deal of work around accessibility and JavaScript-powered interfaces. Along with The Paciello Group he has created a version of the jQuery UI library which has been fully optimised for keyboard navigation and screen reader use. It’s a fantastic reference which I revisit all the time I’m not a huge fan of the jQuery UI library. It’s a pain to style and the code is a bit bloated. So I’ve not used this demo as a code resource to copy wholesale. I use it by playing with the various components and seeing how they react to keyboard controls. Each component is also fully marked up with the relevant ARIA roles to improve screen reader announcement where possible (more on this below). Coding for accessibility promotes good habits This is a another observation around accessibility and JavaScript. I noticed an improvement in the structure and abstraction of my code when I started adding keyboard controls to my interface elements. Your code has to become more modular and event-driven, because any number of events could trigger the same interaction. A mouse-click, the Enter key and the space bar could all conceivably trigger the same open function on a collapsed accordion element. (And you want to keep things DRY, don’t you?) If you aren’t already in the habit of separating out your interface functionality into discrete functions, you will be soon. var doSomethingCool = function(){ // Do something cool here. } // Bind function to a button click - pretty vanilla $('.myCoolButton').on('click', function(){ doSomethingCool(); return false; }); // Bind the same function to a range of keypresses $(document).keyup(function(e){ switch(e.keyCode) { case 13: // enter case 32: // spacebar doSomethingCool(); break; case 27: // escape doSomethingElse(); break; } }); To be honest, if you’re doing complex UI stuff with JavaScript these days, or if you’ve been building any responsive interfaces which rely on JavaScript, then you are most likely working with an application framework such as Backbone, Angular or Ember, so an abstraced and event-driven application structure will be familar to you. It should be super easy for you to start helping out your keyboard-only users if you aren’t already — just add a few more event bindings into your UI layer! Manipulating the tab order So, you’ve adjusted your mindset and now you test every change to your codebase using a keyboard as well as a mouse. You’ve applied all your hover states to :focus and :active so you can see where you’re tabbing on the page, and your interactive components react seamlessly to a mixture of mouse and keyboard commands. Feels good, right? There’s another level of optimisation to consider: manipulating the tab order. Certain DOM elements are naturally part of the tab order, and others are excluded. Links and input elements are the main elements included in the tab order, and static elements like paragraphs and headings are excluded. What if you want to make a static element ‘tabbable’? A good example would be in an expandable accordion component. Each section of the accordion should be separated by a heading, and there’s no reason to make that heading into a link simply because it’s interactive. <div class="accordion-widget"> <h3>Tyrannosaurus</h3> <p>Tyrannosaurus; meaning "tyrant lizard"...<p> <h3>Utahraptor</h3> <p>Utahraptor is a genus of theropod dinosaurs...<p> <h3>Dromiceiomimus</h3> <p>Ornithomimus is a genus of ornithomimid dinosaurs...<p> </div> Adding the heading elements to the tab order is trivial. We just set their tabindex attribute to zero. You could do this on the server or the client. I prefer to do it with JavaScript as part of the accordion setup and initialisation process. $('.accordion-widget h3').attr('tabindex', '0'); You can apply this trick in reverse and take elements out of the tab order by setting their tabindex attribute to −1, or change the tab order completely by using other integers. This should be done with great care, if at all. You have to be sure that the markup you remove from the tab order comes out because it genuinely improves the keyboard interaction experience. This is hard to validate without user testing. The danger is that developers will try to sweep complicated parts of the UI under the carpet by taking them out of the tab order. This would be considered a dark pattern — at least on my team! A farewell ARIA This is where things can get complex, and I’m no expert on the ARIA specification: I feel like I’ve only dipped my toe into this aspect of coding for accessibility. But, as with WCAG, I’d like to demystify things a little bit to encourage you to look into this area further yourself. ARIA roles are of most benefit to screen reader users, because they modify and augment screen reader announcements. Let’s take our dinosaur accordion from the previous section. The markup is semantic, so a screen reader that can’t handle JavaScript will announce all the content within the accordion, no problem. But modern screen readers can deal with JavaScript, and this means that all the lovely dino information beneath each heading has probably been hidden on document.ready, when the accordion initialised. It might have been hidden using display:none, which prevents a screen reader from announcing content. If that’s as far as you have gone, then you’ve committed an accessibility sin by hiding content from screen readers. Your user will hear a set of headings being announced, with no content in between. It would sound something like this if you were using Chromevox: > Tyrannosaurus. Heading Three. > Utahraptor. Heading Three. > Dromiceiomimus. Heading Three. We can add some ARIA magic to the markup to improve this, using the tablist role. Start by adding a role of tablist to the widget, and roles of tab and tabpanel to the headings and paragraphs respectively. Set boolean values for aria-selected, aria-hidden and aria-expanded. The markup could end up looking something like this. <div class="accordion-widget" role="tablist"> <!-- T-rex --> <h3 role="tab" tabindex="0" id="tab-2" aria-controls="panel-2" aria-selected="false">Utahraptor</h3> <p role="tabpanel" id="panel-2" aria-labelledby="tab-2" aria-expanded="false" aria-hidden="true">Utahraptor is a genus of theropod dinosaurs...</p> <!-- Dromiceiomimus --> </div> Now, if a screen reader user encounters this markup they will hear the following: > Tyrannosaurus. Tab not selected; one of three. > Utahraptor. Tab not selected; two of three. > Dromiceiomimus. Tab not selected; three of three. You could add arrow key events to help the user browse up and down the tab list items until they find one they like. Your accordion open() function should update the ARIA boolean values as well as adding whatever classes and animations you have built in as standard. Your users know that unselected tabs are meant to be interacted with, so if a user triggers the open function (say, by hitting Enter or the space bar on the second item) they will hear this: > Utahraptor. Selected; two of three. The paragraph element for the expanded item will not be hidden by your CSS, which means it will be announced as normal by the screen reader. This kind of thing makes so much more sense when you have a working example to play with. Again, I refer you to the fantastic resource that Hans Hillen has put together: this is his take on an accessible accordion, on which much of my example is based. Conclusion Getting complex interfaces right for all of your users can be difficult — there’s no point pretending otherwise. And there’s no substitute for user testing with real users who navigate the web using assistive technology every day. This kind of testing can be time-consuming to recruit for and to conduct. On top of this, we now have accessibility on mobile devices to contend with. That’s a huge area in itself, and it’s one which I have not yet had a chance to research properly. So, there’s lots to learn, and there’s lots to do to get it right. But don’t be disheartened. If you have read this far then I’ll leave you with one final piece of advice: don’t wait. Don’t wait until you’re building a site which mandates AAA-compliance to try this stuff out. Don’t wait for a client with the will or the budget to conduct the full spectrum of user testing to come along. Unplug your mouse, and start playing with your interfaces in a new way. You’ll be surprised at the things that you learn and the issues you uncover. And the next time an true accessibility project comes along, you will be way ahead of the game. | 2013 | Charlie Perrins | charlieperrins | 2013-12-03T00:00:00+00:00 | https://24ways.org/2013/coding-towards-accessibility/ | code |