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Re: Caption@title instead of table@summary?

From: Leif Halvard Silli <lhs@malform.no>
Date: Wed, 18 Feb 2009 16:08:41 +0100
Message-ID: <499C2479.8030808@malform.no>
To: joshue.oconnor@cfit.ie
CC: Maciej Stachowiak <mjs@apple.com>, HTMLWG <public-html@w3.org>
Joshue O Connor 2009-02-18 12.39:
> Maciej Stachowiak wrote:
>> Interesting idea. I think the core tradeoff between <caption title="">
>> and <table summary=""> is whether the additional information is
>> accessible (in some way) to sighted users. 
> 
> No its not. The difference is between some thing that facilitates
> comprehension for a user that /needs/ this information and something
> that is optional for a user who can already comprenend it. For example,
> a sighted user can quickly glance at a table and understand the
> relationships between various headers and row and column relationships.
> A non sighted user, has to interogate the table. @summary is useful as
> it does some of this work for the user because the user is informed in
> advance of what the table contains. It could be compared to a look ahead.

I agree with this description of the purpose of summary. And I 
doubt that the usefullness of a such lookahead feature can be 
disputed.

So if what I said is true, namely that:

>>>   * It is possible that some users would be annoyed by seeing the
>>>     @title content when hovering over <caption>.

then those that have said that @summary, if useful, would be just 
as usefull for visual UA users, as for non-visual UA users, are 
wrong. (However, those that think that such info should be *as 
useful* to both usergroups, should now step forward  - again ... )

I see som advantages if it is easy to display a summary as a title 
tooltip. But I could also imagine that it could be annoying to see 
such info which only duplicates what one can see by looking at the 
  table. This, that it is possible to see the table anyhow, could 
also shape how authors ues the caption title: perhaps they would 
only insert info that is useful to sighted users? Or, perhaps one 
would avoid filling any content into <caption>, since then the 
title tooltip would also not display.

>> One reason we have both
>> title="" and alt="" on <img> is specifically to discourage UAs from
>> displaying alt to sighted users, since then it tends to contain
>> auxiliary information instead of replacement text. On the other hand, a
>> table summary should actually be auxiliary information about the table -
>> it doesn't need to fully replace the table because the table is still
>> there to be navigated if the user desires.
> 
> Yes.
-- 
leif halvard silli
1
Received on Wednesday, 18 February 2009 15:09:24 UTC

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