[whatwg] Drop tabindex=""

[Maciej Stachowiak]

On Mar 20, 2007, at 8:16 PM, Simon Pieters wrote:

> Hi,
>
> I think tabindex="" has a number of problems:
>
> 1) Lacking a feature to scope tabindexes into local contexts, which  
> I proposed[1] a while back, makes the feature rather useless for  
> its intended purpose (which, AIUI, was to provide a means for the  
> author to suggest a different tab order than the natural one,  
> because he was using, say, form controls in a table where the  
> navigation should go down through the columns rather than row for  
> row).

Sounds like such a feature could be useful, but it would be tricky to  
make it compatible with older UAs.

>
> 2) Using tabindex=0 or -1 to indicate whether an element can have  
> focus is arguably bogus IMHO. Whether something is focusable  
> depends on the UA or the device. I don't see any reason why apps  
> would use <span tabindex=0 onclick onkeypress> instead of just  
> using links, form controls, or contenteditable="" (depending on  
> what you're doing). (If you'd do this because form controls are  
> hard to style, then HTML isn't the place to address that problem.)

I disagree with this. Arbitrary elements accepting keyboard input  
(which is what focus is about) is just as important as arbitrary  
elements receiving mouse input. You even cited one of my examples  
below: consider a game implemented with <canvas> that uses keyboard  
controls. Obviously you want to be able to make <canvas> focusable in  
such cases. There are many analogous use cases, consider building  
compound controls with XBL that want to have their own keyboard  
navigation. I don't think there is any need to limit what elements  
can get keyboard input

> 3) The "tab order" should be up to the user. In Opera you can  
> navigate in any direction you want using e.g. Shift+arrows,  
> allowing you to freely navigate in tables for instance. The author  
> shouldn't have any say about the tab order other than the source  
> order.

Shift+arrows are a completely separate issue from "tab order".

> From what I've seen, most authors who use tabindex use it out of a  
> cargo cultish habit thinking it would "aid accessibility" because  
> some outdated accessibility guidelines told them so. The result  
> mostly being reducing keyboard usability by distorting the tab  
> order, because the elements with tabindex receive focus before  
> anything else on the page. These authors don't realise how tabindex  
> actually works, but they feel good about having added it because  
> they comply with the accessibility guidelines, yet they don't know  
> that it in fact screws up the tab order because they don't browse  
> with the keyboard.

This sounds like something to be fixed in the relevant accessibility  
guidelines. HTML5 can also recommend not adding these attributes  
gratuitously.

> It was pointed out on IRC that there might be valid use-cases for  
> #2, e.g. making a <canvas> focusable for games with keyboard  
> controls. Then that's ok with me, I don't have strong opinions on  
> this either way, I just think existing elements should be used  
> where possible instead of reinventing links or checkboxes with  
> <span tabindex> or similar.

I agree that existing elements should be used when possible, but  
sometimes none of the small set of elements that is focusable by  
default is suitable. Note that UAs do not even agree on what elements  
are focusable by default. In Safari, links and <input type="button">  
controls are not in the tab order, for instance, to match Macintosh  
UI conventions.

> However, for positive values of tabindex, I only see problems. The  
> source order should be a powerful enough mechanism for authors to  
> suggest a tab order of elements.

Document order is insufficient in the presence of positioning, or the  
column vs. row example you cited.

> I would love to see browsers treat all positive values for tabindex  
> as equivalent to 0 (i.e., just make it focusable but don't change  
> the tab order). I would also like to propose that positive values  
> for tabindex be disallowed in HTML5 documents. I don't think it's a  
> good idea to add a scoped tabindex feature (trying to address #1)  
> as I proposed before.
>
> [1] http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2006-August/ 
> 007228.html
>
> Regards,
> -- 
> Simon Pieters