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Re: longdesc - beside the box

From: Benjamin Hawkes-Lewis <bhawkeslewis@googlemail.com>
Date: Tue, 26 Apr 2011 16:48:16 +0100
Message-ID: <BANLkTikhWSyuyKux2a1OGG3pCOAOUSvbsQ@mail.gmail.com>
To: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
Cc: John Foliot <jfoliot@stanford.edu>, HTMLWG WG <public-html@w3.org>
On Tue, Apr 26, 2011 at 3:32 PM, Leif Halvard Silli
<xn--mlform-iua@xn--mlform-iua.no> wrote:
> Benjamin Hawkes-Lewis, Tue, 26 Apr 2011 13:55:58 +0100:
>> On Tue, Apr 26, 2011 at 12:22 PM, Leif Halvard Silli  wrote:
>>> Benjamin Hawkes-Lewis, Tue, 26 Apr 2011 10:16:32 +0100:
>>>> On Tue, Apr 26, 2011 at 2:57 AM, Leif Halvard Silli wrote:
>>>>> iCab does show a "default visual encumbrance" for images with
>>>>> @longdesc.
>>>>
>>>> The user has to take a special action (hovering over the image) to
>>>> display the encumbrance (a cursor change), so it's not "default".
>>>
>>> That's the same for many links: until you hover above them, you don't
>>> see it is a link.
>   [...]
>> @longdesc is hidden metadata by design;
>
> The 'Techniques for User Agent Accessibility Guidelines 1.0' from 2002
> did not design it as hidden:
>
> http://www.w3.org/TR/UAAG10-TECHS/guidelines#long-descriptions

No popular user agent presents a "forced visual encumberance" for
@longdesc, and @longdesc's lack of a "forced visual encumberance"
is a major plank in the rationale for making it conforming that
has been presented to the WG.

>> hyperlinks and most aspects of
>> microformats are visible data by design.
>
> While, as you said, it is considered good to use underlining for links,
> it is probably more important what happens with the cursor.

I disagree.

> Not least because links where the image is the sole content do not get
> any underlining by default.
>
> Thus an image that is a link is in fact (easy) discoverable meta data
> and not visible data - by today's design.
>
> (The blue frame around images disappeared because it was considered
> ugly, but it can in fact still be seen on img elements with @usemap in
> Internet Explorer [in some modes, at least].)

In practice image links tend to have visual traits that identify
them as such long before you hover over them. An image is likely to be
clickable if one of the following is true:

   1. It's a thumbnail.
   2. It's got a play icon superimposed.
   3. It's visually associated with a text link to an article.
   4. It's presented as one of a list of images.
   5. It's an icon.

In so far as image links are indistinguishable from unclickable images,
the encoding of the relationship part of their data follows the hidden
metadata antipattern to their detriment.

> Wether there by *default* should be visible indicator on the picture
> itself - that's a detail that we still need to discuss more.

I think the debate about how to handle long descriptions in HTML is
mostly about this question of whether we need to provide features
dedicated to making them invisible. Much as with table summaries.

--
Benjamin Hawkes-Lewis
Received on Tuesday, 26 April 2011 15:48:47 GMT

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