HTML5 Doctor » aria

Your Questions Answered #4

Richard Clark — Wed, 09 Dec 2009 08:52:14 +0000

Here we go with another post rounding up your HTML5 questions and sharing the answers with the world. We cover a wide range of topics this time, inlcluding ARIA, storage, offline capabilities, and document outlines, so read on to find the answers.

We also want to know what areas of HTML5 you’d like us to cover in future articles, so let us know!

Older browsers and XHTML

Brett Prichard asked:

If I were to use one of the new tags in HTML5, (i.e., or
) what would happen when the page is rendered by an older browser?

The other question I have is will there be an XHTML equivalent? XHTML 2.0 breaks off compatibility with HTMLs 1-4, but will it be compatible with HTML5? I prefer to code in XHTML.

Thank you for reading.

To answer your first question: nothing special. The content nested within the element is displayed. (In the case of video, the fallback content is shown.)

Regarding your second question, I wrote about the XHTML serialisation of HTML5 a while ago.

— Thanks, Bruce

ARIA

Joseph Chapman asked:

My colleagues and I wish to switch our doctype to the streamlined and implement several things we learnt from Jeremy Keith last Wednesday, primarily ARIA.

We know that support is good as long as we add an extra DTD, but we can’t find the appropriate doctype declaration to stick on the end of ...html> Any ideas? We are really keen to kick this off and use a new piece of technology that will help springboard our site to a new level of accessibility.

Any answers appreciated.

Thanks for your help.

It’s okay to add ARIA to HTML5 now without using a different doctype. I suggest you give this part of the spec a read.

I believe a task force has been created to more closely align ARIA to HTML5. We plan to cover ARIA more in a future post.

Hope this helps

— Rich

Attribute Minification

Nick Leon asked:

Hey there HTML5Doctor,

I consider myself a strong POSH developer. One of the requirements for valid XHTML is that “attribute minimization” is not allowed. HTML permits “attribute minimization”, where boolean attributes can have their value omitted entirely, e.g., . All XML attributes must have explicit quoted values, so in XML this would be written as .

I was wondering where HTML5 stands with attribute minimization. I noticed in some of your example code, you provided the minimized form of the attribute, e.g., . Is this valid in HTML5? Would this be the valid version for XHTML5:

?

Those are both valid HTML5 structures (however, controls=”1″ isn’t legal; you need to say controls=”controls”).

In HTML5, you can format attributes as you please. In XHTML5 (the XML serialisation), you need to obey the XML rules.

— Cheers, Bruce

Offline storage

Kevin Searle asked:

I’m having a hard time wrapping my head around the offline storage capabilities of the HTML 5 spec. Can you consider an “HTML 5 Offline Storage 101″ article?

Just to clarify, do you mean “storage” or “offline”? They’re two very different things.

Storage relates to variables, like cookie jars but a lot bigger.

Offline applications are about detecting connectivity and possibly running your app without a connection to the Web.

We (i.e., Remy) will be writing about both of these topics, but it’s useful to know which is more in demand than the other.

In the meantime, feel free to check out the demos I’ve written at HTML5 Demos (covering offline, storage, and web databases).

— Remy

Nav Title (in the document outline)

D Ross asked:

Working on my new site and checked it with the outliner. I’m getting an “untitled section” showing up because I don’t have a headline inside my “nav” element.

Is this correct? Do I really need to title my main nav?

If so, is adding an
or something similar with the words “main navigation” good enough? If so, is hiding it with display: none okay?

Thanks,

DRoss

Yes, “untitled section” is fine. I know it’s been suggested to the developer of the outliner that it should say “navigation” or something similar, but I’m not sure when or whether that will happen. (You’ll see the same thing with

too if there’s no heading nested directly beneath the element).

Thanks,

— Rich

The details element

Bart asked:

Hello Doctors!

I’d like to ask you a little help with understanding the “details” element.

As the W3 spec says: “The details element represents a disclosure widget from which the user can obtain additional information or controls”.

I’m not sure if I get it right, but I think I can use this element to put details about a post (such as date and time) and controls, including “answer”, “save” and “repost”.

Please tell me if I’m wrong.

Regards, Bart

PS. I love the HTML5doctor blog, it’s so important to explain how to use HTML5. Keep up the great work!

This question triggered a flurry of responses from several of us doctors, so we’ve added them all here for you.

Answer 1

The spec says

is not appropriate for footnotes, and you could argue that post details are footnotes. Also, the

element has the option to show or hide its content, which suggests to me that it’s not appropriate for the post details.

You could possibly use a

or a

for the post details, but I’m not clear on what you mean by “controls”.

For the date/time, you can use the element:

September 23rd, 2009

Other doctors might have other opinions, but I hope this helps.

— Tom

Answer 2

Just to follow up on Tom’s reply: the user viewing your content can control whether or not they see the details.

The

element is an interactive element that is collapsed by default, so that only the heading is visible. The heading should be marked up in a

element (if absent, it will read “Details”).

The control that the user agent should render (when fully supporting the

element) is a small triangular button to the left that, when clicked, toggles the visibility of the element’s contents.

If the

element should be open by default, it should have its open attribute set.

I would use

for any content that still allows the surrounding content to make sense while not necessarily needing to be seen. So in your example, I would put the metadata in the

, but not the “user controls” to reply, save, etc., since the user should always be able to see that they can perform these actions.

While the browser vendors haven’t implemented the interactive aspect of details, I, for one, will be emulating this using JavaScript.

I hope that helps (too!).

— Remy

Answer 3

You can also use pubdate as an attribute of :

September 23rd, 2009

pubdate is useful when you have two different times in the post. For example, for a future event:



Gig: Hixie and the Pixies, Jan 1st 2010, Royal Albert Hall
Published Sept 21, 2009

With Lachy on kazoo, Henri on Sousaphone, Pilgers on the triangle, and Hixie conducting

I feel a post about the element coming on…

— Bruce

More to come

That wraps up this round of questions! We’d like to know what areas of HTML5 you’d like us to cover in future articles, so leave a comment below or send us an e-mail.

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Your Questions Answered #4 originally appeared on HTML5 Doctor on December 9, 2009.

Accessibility & Native Drag and Drop

Remy Sharp — Thu, 23 Jul 2009 13:30:32 +0000

A few days before my native drag and drop article came out Gez Lemon wrote about accessibility in drag and drop, and touched on HTML 5.

I then promised to look at implementing accessibility with native drag and drop, and here’s my findings.

ARIA Support

This was quite easy to add, though only by following Gez’s article. Since I already had events for drag start, I just needed to add drag end to clean up and remove the ARIA effects.

I added the following to the dragstart event:

addEvent(dragItems, 'dragstart', function (event) {
  // via ARIA say the element has been grabbed
  this.setAttribute('aria-grabbed', 'true');
  // code continues...

The added a new dropend event:

addEvent(dragItems, 'dragend', function (event) {
  // remove the ARIA grab attibute when we're not dragging
  this.setAttribute('aria-grabbed', 'false');
});

The effectAllowed and dropEffect combo was difficult to work out at first, though probably because I was playing with link and reference, whereas I should have been playing with move or copy. That said, a note about move and copy, move is a type of copy, with a clean up function to delete afterwards. Once I had this combo correct, the drop effects worked.

The changes required were to:

On drag: on all the drop targets add: setAttribute('aria-dropeffect', 'copy')
On drag: set the allowedEffect on the drag event: event.dataTransfer.effectAllowed = 'copy';
On drop: say what we’ll accept: event.dataTransfer.dropEffect = 'move';
On dragend: remove the drop effect from the drop targets: removeAttribute('aria-dropeffect')

The big problem for me was that I couldn’t truely test this.

Update: between the time I had finished my code and writing this article, NVDA (the Windows open source screenreader) announced that they recieved support from Yahoo!, and that ARIA drag and drop support is in their development roadmap.

The full working version of native drag and drop with ARIA support is available here: native drag and drop with ARIA support (source code)

Keyboard Support

Keyboard, sadly, is a whole different story.

I was able to replicate a lot of the keyboard features that Gez included in his demo. This included setting the tabIndex = 0 to allow the elements to tab to (superb trick by the way), included highlighting the drop targets as we drag.

However, the problem was: I wanted the user to be able to start the drag operation using the keyboard. Initially looking at the spec I couldn’t see that it was supposed to be supported (which it turns out, it is).

I started going down the path of using the keyboard to trigger drag events. I was able to replicate the drag event being triggered from the keyboard (like space starts the event), however, and this is a biggie, I couldn’t replicate the dataTransfer object. I tried faking it. I tried giving it nothing. I tried all kinds of random attempts to trick the browser in to giving me the object. It’s a no goer.

As it turns out, there is keyboard support written in to the spec (though in my personally opinion it’s not completely obvious to an author reading). The drag and drop operations should work like a copy and paste operation.

This is very clever, and I like it. Tab round to the dragable element, copy using the keyboard, which triggers the dragstart event, which I can then add classes to the drop targets, and make them tabbable. The user then tabs round to the drop targets, and pastes. This triggers the drop event and we’re all good.

No browsers support this keyboard event model.

I’ve raised bug for Mozilla and Webkit. They’ve both had comments on, and in both cases I’m not 100% sure what the comments mean, but speaking to the people involved via IRC, they’ve both said if it’s in the spec, it should be in the browser.

Let’s hope they do something about it. Now, how do I report a bug in IE…?!

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Accessibility & Native Drag and Drop originally appeared on HTML5 Doctor on July 23, 2009.

HTML5 Doctor » aria

Your Questions Answered #4

Older browsers and XHTML

ARIA

Attribute Minification

Offline storage

Nav Title (in the document outline)

or something similar with the words “main navigation” good enough? If so, is hiding it with `display: none` okay?

Thanks,

DRoss

Answer 3

Gig: Hixie and the Pixies, Jan 1st 2010, Royal Albert Hall

More to come

Related Posts:

Accessibility & Native Drag and Drop

ARIA Support

Keyboard Support

Related Posts:

HTML5 Doctor » aria

Your Questions Answered #4

Older browsers and XHTML

ARIA

Attribute Minification

Offline storage

Nav Title (in the document outline)

or something similar with the words “main navigation” good enough? If so, is hiding it with display: none okay? Thanks, DRoss

Accessibility & Native Drag and Drop

ARIA Support

Keyboard Support

Related Posts:

or something similar with the words “main navigation” good enough? If so, is hiding it with `display: none` okay?

Thanks,

DRoss