Archive for the 'ARIA' Category

The accessibility of HTML 5 autofocus

Last week, I published an HTML 5 contact form WordPress plugin that used the HTML autofocus attribute to put the focus into the first form field.

Marc Aplet commented about the accessibility of doing that, for which I am very grateful as it made me think more deeply about it. Thanks to those on twitter who helped me further with my thinking.

Note that potential accessibility problems are not restricted to the HTML 5 use of autofocus; current JavaScript ways of doing it cause the same problems.

I believe that autofocussing into a form is a usability win for most people if the purpose of the page is that form—for example, the Google hompage. So, I wouldn’t autofocus into the search box or comment field on this page because the primary purpose of this page is discussing this article which requires prior reading. Most people are lurkers, not commenters, so it’s against usability to autofocus into the comment form. But a contact form is the primary purpose of a contact page, and it saves users a keystroke to put the caret into the first field—particularly usable for mobile phone users.

However, screenreader users find themselves dumped in the middle of a form, potentially without context (athough it’s always possible to tell the screenreader to repeat the title of the page, and we all give our pages useful titles, don’t we?).

Moreover, many forms have explanatory or introductory information preceeding them. My contact form does, although that’s somewhat flippant. A better example is Salford University’s Online Staff Directory Quick Search Page. The explanatory information is correctly outside the form element, as JAWS and (I think) Windows-Eye ignore any text that’s not inside legend and label elements when they’re in Forms mode.

What we need, then, is a way to associate some explanatory descriptive text that’s outside the form with the form itself (in a similar way that label and input are explicitly associated). Then a screenreader user could be alerted to the presence of this descriptive material by this programmatic association, and optionally choose to have it read out to them.

Enter aria-describedby. The ARIA spec says

An accessible description may be computed by concatenating the text equivalents for nodes pointed to by an aria-describedby attribute on the current node.

So, I recoded the plugin (download it; it’s at your own risk etc) so that the descriptive matter is enclosed in a div id="form-description". The form element has the attribute aria-describedby="form-description" (because the description is for the whole form).

I don’t know if any screenreaders offer a keystroke to query this information yet (it’s over a year since I’ve been near a screenreader), but as the vendors have worked closely with the WAI-ARIA authors I imagine it won’t be long.

I also amended the plugin so that it has a belt-and-braces approach to the form fields that are required. In addition to the HTML 5 required attribute, I’ve added aria-required="true" as this is probably closer to implementation by screenreader vendors.

Because there are already two programmatic methods of indicating that a field is required, I’ve removed the traditional method of including an asterisk in the markup, as it’s possible to style the form fields with CSS—I’ve used a thick black border. (I tried to use attribute selectors to generate the string “required” immediately after the form field, but that gets surrounded by the field border rather than living outside it. The result is minging, even by this site’s low design standards.)

Welcome Molly, free HTML 5 talk on Saturday

I’m delighted that my old mate Molly Holzschlag is joining the Web Evangelist team at Opera.

I’ve known Molly since 2001. She was a journalist covering a Wrox XML conference I was helping run in Las Vegas. A colleague of mine, Karli Watson had a quickie, tacky Vegas wedding and Molly and I attended.

Two years later, I was searching for someone to co-author a book with me about usability, and found Molly. We were both unaware that we’d met before until halfway through our collaboration. Usability: the site speaks for itself sold poorly (and taught me some vital lessons about web developers and how they differ from programmers) but it cemented my friendship with Molly. She’s been to my house, eaten my evil chicken, charmed my children (“a real American!”) and helped me drink a bottle of vodka.

It’s great to work with old friends like Molly, Millsy and Jon Hicks, and new friends like “Zip Pin” Zi Bin, Shwetank, David-not-Dave, Andreas “Frisky” Bovens and Henny “Henry” Swan. One of the comments on Molly’s blog is “That’s some team Opera are building.” Fuck, yeah. And I’m delighted to be a part of it.

Why the mobile web must mirror the desktop

A long interview with me about One Web and the importance of web standards for device-independent development, which will presumably get Luca all foamy at the mouth again. Originally published in .net magazine a month ago.

Free talks on HTML 5, ARIA and JavaScript, Birmingham 21 February

I’ll be presenting “Confessions of a mad scientist: my HTML 5 experiments” on Saturday at 4pm in Birimingham (meet at 2pm for beers).

Also on the bill is Stuart Langridge on JavaScript and another old friend, Matt Machell, discussing ARIA. It’s free, so see you there? (More details)

HTML 5 Flash embedding and other validation errors

When I completed the first round of my HTML 5 redesign, some validation errors remained.

Most were due to WAI-ARIA roles being applied to new HTML 5 structural elements, which isn’t currently allowed (both specs are in draft, remmeber). I’m not worried about those; accessibility trumps validity for me, and ARIA doesn’t validate in HTML 4, either.

I was also getting an odd error with Remy Sharp’s groovy HTML 5 enabling script, which I’d surrounded by a conditional comment as only Internet Explorer needs it. Part of the JavaScript has a double hyphen and HTML 5 doesn’t like “--” in comments, so fearphage sent me a rewrite that reversed the JavaScript. You don’t need to do this as you would have the script in an external file; I have it included in the head of each page so that visitors can see what’s happening.

However, none of the embedded Flash movies from YouTube would validate. I was using the default code given by YouTube which nests an embed tag inside an object tag and which doesn’t validate in current flavours of (X)HTML because embed was never in any spec.

Fearphage suggested using just the object tag for the Flash movies, but Patrick Lauke pointed out that there are some problems with that approach:

  • Internet Explorer can’t stream videos but must download the full movie before showing it
  • screenreaders can’t access accessibility information within the Flash movie (admittedly not likely to be a problem with most YouTube uploads)

One of the HTML 5 design principles is to “pave the cowpaths”. Because everybody uses embed, it’s been added to the spec. So by rearranging some of YouTube’s suggested code (self-closing param elements, escaping ampersands in URLs and repeating the URL for a third time as a data attribute on the object element) I came up with an accessible-as-possible, cross-browser, valid HTML 5 way to embed Flash movies:

<object width="425" height="344" data="http://www.youtube.com/v/8-pFwbHMuwA&amp;hl=en&amp;fs=1">
<param name="movie" value="http://www.youtube.com/v/8-pFwbHMuwA&amp;hl=en&amp;fs=1" />
<param name="allowFullScreen" value="true" />
<param name="allowscriptaccess" value="always" />
<embed src="http://www.youtube.com/v/8-pFwbHMuwA&amp;hl=en&amp;fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344" />
</object>

What we need now is for some kind soul to write a wizard that converts YouTube’s default code into code formatted as above.

It’s with some irony that I write this post, because one of the exciting things about HTML 5 is the video element that allows video to be added to a page with a simple <video src="blah.src" controls>I'm fallback content</video> and then plays it without any plugins or scripting. It allows an open, patent-free video codec to interact with canvas and SVG and it doesn’t require duplication of data twice or three times like the code contortions above.

Unfortunately it’s usefulness is mired in politics—see David Storey’s The future of video on the Web.

I’m too lazy to amend every instance from the last five years, but my home page is now valid apart from ARIA roles and an objection to the feed: protocol on a link to my RSS feed.

Thanks Patrick and fearphage.

Government guidelines, ARIA, microformats

Not so much a blog post but a collection of links.

UK government browser guidelines: good sense prevails

The Web Standards community changed some guidelines for government webmasters that would encourage designing to browsers into something that requires valid code, web standards and progressive enhancement. UK government browser guidelines: good sense prevails.

Talking of guidelines, I’m doing a short talk on Wednesday about BS 8878: Web accessibility – Building accessible experiences for disabled people at the Oxford Geek Night. See you there?

How Can I Validate (X)HTML + ARIA?

A while ago I speculated that the lack of a validator for ARIA might slow adoption. Steve Faulkner has written a proof-of-concept HTML4+ARIA Checker and hopes, as I do, that “the W3C validator adds support for (X)HTML +ARIA documents so I when check a document and it contains no errors in the HTML (except for the use of ARIA) and ARIA code, I see a message like this: this document was successfully checked. Passed (1 Warning)”

Should you think that ARIA is just w3c vapourware, there’s a podcast on ARIA by Freedom Scientific (the manufacturers of the JAWS screenreader) available:

Freedom Scientific’s Chief Technical Officer Glen Gordon explains ARIA and its benefits. Jonathan Mosen then demonstrates some applications with ARIA enabled for improved accessibility.

Didn’t see a transcript anywhere, surprise surprise.

More bandaids for microformats

Pat “Herb” Lauke wonders “if we should have an official anniversary each year where the same microformat/accessibility issue is rehashed” and links to an experiment by Andy Clarke. It’s a nice idea, but I think it’s a bandaid. I agree with Isofarro’s diagnosis:

It boils down to this: the title attribute is meant for human consumable content, just the same as the inner text of most of the HTML elements.

Everytime you put machine-formatted data into a container that is for human consumption, then you run the risk of it being exposed to a human being. In microformats this a ‘feature’, in accessibility this a ‘bug’.

I think that’s throwing the baby out with the bathwater to say “the easiest approach right now is to say Microformats are inaccessible, and move along”; it’s just this pattern that’s inaccessible.

Patrick suggests, “why not make a ‘title attribute’ pattern that allows for the use of the most semantically appropriate element? span with title in cases like datetime, abbr when it is actually an abbreviation.”

That makes sense to me. How would those plugins that make use of microformats cope if I marked up hCalendar dates with a span. Anyone know?