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Thread: Table SUMMARY Tag
Number of posts in this thread: 9 (In chronological order)
From: ejp10
Date: Wed, Mar 02 2011 8:24AM
Subject: Table SUMMARY Tag
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Due to the various legal issues, our university is looking to improve implementation of accessibility.
One suggestion I have heard is to include a SUMMARY attribute for every HTML table, but I am seeing conflicting information about it.
Some sources say the summary is to summarize trends in the data, but others say it is to specify table structure (although I thought the CAPTION tag and the SCOPE/headers tags dis that as well. What are opinions on this topic? Are there any good sources of code snippets we could look at?
Any information/opinions appreciated.
Thanks
Elizabeth
=-=-=-=-=-=-=-=-=-=-=-=-Elizabeth J. Pyatt
Instructional Designer
From: Langum, Michael J
Date: Wed, Mar 02 2011 8:54AM
Subject: Re: Table SUMMARY Tag
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Ms Pyatt,
The summary attribute is not visually displayed in a browser. It's purpose is to assist users of assistive technology to understand the structure of the table. E.g.
<table summary="this table lists responses to survey questions by sub-group. Responses for each sub-group are provided as absolute numbers, and percentage of whole.">
-- Mike
-----Original Message-----
From: = EMAIL ADDRESS REMOVED = [mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of ejp10
Sent: Wednesday, March 02, 2011 10:25 AM
To: = EMAIL ADDRESS REMOVED =
Subject: [WebAIM] Table SUMMARY Tag
Due to the various legal issues, our university is looking to improve implementation of accessibility.
One suggestion I have heard is to include a SUMMARY attribute for every HTML table, but I am seeing conflicting information about it.
Some sources say the summary is to summarize trends in the data, but others say it is to specify table structure (although I thought the CAPTION tag and the SCOPE/headers tags dis that as well. What are opinions on this topic? Are there any good sources of code snippets we could look at?
Any information/opinions appreciated.
Thanks
Elizabeth
=-=-=-=-=-=-=-=-=-=-=-=-Elizabeth J. Pyatt
Instructional Designer
From: Barker.Diane
Date: Wed, Mar 02 2011 9:03AM
Subject: Re: Table SUMMARY Tag
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Hi,
More information can be found here -
http://www.w3.org/TR/WCAG20-TECHS/H73.
Diane
-----Original Message-----
From: = EMAIL ADDRESS REMOVED =
[mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of Langum,
Michael J
Sent: Wednesday, March 02, 2011 7:53 AM
To: 'WebAIM Discussion List'
Subject: Re: [WebAIM] Table SUMMARY Tag
Ms Pyatt,
The summary attribute is not visually displayed in a browser. It's
purpose is to assist users of assistive technology to understand the
structure of the table. E.g.
<table summary="this table lists responses to survey questions by
sub-group. Responses for each sub-group are provided as absolute
numbers, and percentage of whole.">
-- Mike
-----Original Message-----
From: = EMAIL ADDRESS REMOVED =
[mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of ejp10
Sent: Wednesday, March 02, 2011 10:25 AM
To: = EMAIL ADDRESS REMOVED =
Subject: [WebAIM] Table SUMMARY Tag
Due to the various legal issues, our university is looking to improve
implementation of accessibility.
One suggestion I have heard is to include a SUMMARY attribute for every
HTML table, but I am seeing conflicting information about it.
Some sources say the summary is to summarize trends in the data, but
others say it is to specify table structure (although I thought the
CAPTION tag and the SCOPE/headers tags dis that as well. What are
opinions on this topic? Are there any good sources of code snippets we
could look at?
Any information/opinions appreciated.
Thanks
Elizabeth
=-=-=-=-=-=-=-=-=-=-=-=-Elizabeth J. Pyatt
Instructional Designer
From: Jukka K. Korpela
Date: Wed, Mar 02 2011 11:09AM
Subject: Re: Table SUMMARY Tag
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ejp10 wrote:
> Due to the various legal issues, our university is looking to improve
> implementation of accessibility.
Does the applicable legislation say something about SUMMARY attributes? (It
might, probably indirectly, by normatively referring to specifications that
discuss it.)
> One suggestion I have heard is to include a SUMMARY attribute for
> every HTML table, but I am seeing conflicting information about it.
There are indeed conflicts, but it would certainly be wrong to say that
_every_ table must have a SUMMARY attribute. WCAG 2.0 tech document
http://www.w3.org/TR/WCAG-TECHS/H73.html clearly says that layout tables
should _not_ have a SUMMARY attribute or should at most have an empty
SUMMARY attribute (summary=""). It also describes the attribute as something
needed for _complex_ tables.
> Some sources say the summary is to summarize trends in the data, but
> others say it is to specify table structure (although I thought the
> CAPTION tag and the SCOPE/headers tags dis that as well.
This is a somewhat obscure area, and I would say that if the attribute is
used, its value should be such that it is useful to a person who does not
see the table as a whole but needs to process it sequentially or by
accessing cells by column and row headings or numbers. What this implies
depends on the context and structure.
On the other hand, the HTML5 drafts designate the SUMMARY attribute as
obsolete and declare that authors must not use it. Whatever we think of
HTML5, it seems to be the way the world is going. I guess the reason for
making SUMMARY as obsolete is twofold: first, it has fairly limited support
and usage; second, it is better replaced by explanations that every user can
make use of.
--
Yucca, http://www.cs.tut.fi/~jkorpela/
From: Joshue O Connor
Date: Thu, Mar 03 2011 2:36AM
Subject: Re: Table SUMMARY Tag
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On 02/03/2011 18:09, Jukka K. Korpela wrote:
> On the other hand, the HTML5 drafts designate the SUMMARY attribute as
> obsolete and declare that authors must not use it. Whatever we think of
> HTML5, it seems to be the way the world is going. I guess the reason for
> making SUMMARY as obsolete is twofold: first, it has fairly limited support
> and usage; second, it is better replaced by explanations that every user can
> make use of.
FWIW For the first point, @Summary is very well supported in most
browsers, it is recognised by most screen reading AT and announced as
soon as the table is given focus.
For the second, while on paper this looks like a good idea, removing
@summary from HTML 5 because it couldn't be used by _everybody_ became a
Shibboleth that lost all meaning. @summary content could be exposed to
sighted users if browsers were wired to do so.
The fact is (IMO of course), that what @summary did/does for blind users
it actually does very well. The fact that it didn't do it for _all_
users, was its death knell. Which to me, is a pity. While philosophies
like Universal Design are great, I would rather see elements and
attributes that support some user groups very well, than elements and
attributes that serve all users poorly.
The two choices may not be even be mutually exclusive but c'est la guerre.
Cheers
Josh
NCBI: Celebrating 80 Years
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From: adam solomon
Date: Thu, Mar 03 2011 1:03PM
Subject: Re: Table SUMMARY Tag
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The idea that information should be equal for sighted users and assistive
tech, as it relates to our discussion of the summary attribute, is a very
romantic idea - unfortunately in my humble opinion it is not practical. The
fact is that extra descriptive information about a table which can really
help out an AT user, will never be allowed in by a web designer on the basis
that it is superfluous, and that it does not fit in to their wonderful
design. So, in effect, we are only hurting the AT user. As a matter of fact,
I see more and more developers turning to hidden texts to provide necessary
info for the AT users, so by removing the summary attribute, all we will be
doing is to force the developer to add more hidden text where the is a
complex table. Too bad.
On Thu, Mar 3, 2011 at 11:36 AM, Joshue O Connor < = EMAIL ADDRESS REMOVED = >wrote:
> On 02/03/2011 18:09, Jukka K. Korpela wrote:
> > On the other hand, the HTML5 drafts designate the SUMMARY attribute as
> > obsolete and declare that authors must not use it. Whatever we think of
> > HTML5, it seems to be the way the world is going. I guess the reason for
> > making SUMMARY as obsolete is twofold: first, it has fairly limited
> support
> > and usage; second, it is better replaced by explanations that every user
> can
> > make use of.
>
> FWIW For the first point, @Summary is very well supported in most
> browsers, it is recognised by most screen reading AT and announced as
> soon as the table is given focus.
>
> For the second, while on paper this looks like a good idea, removing
> @summary from HTML 5 because it couldn't be used by _everybody_ became a
> Shibboleth that lost all meaning. @summary content could be exposed to
> sighted users if browsers were wired to do so.
>
> The fact is (IMO of course), that what @summary did/does for blind users
> it actually does very well. The fact that it didn't do it for _all_
> users, was its death knell. Which to me, is a pity. While philosophies
> like Universal Design are great, I would rather see elements and
> attributes that support some user groups very well, than elements and
> attributes that serve all users poorly.
>
> The two choices may not be even be mutually exclusive but c'est la guerre.
>
> Cheers
>
> Josh
>
>
> NCBI: Celebrating 80 Years
>
> ********************************************************************
> National Council for the Blind of Ireland (NCBI) is a company
> limited by guarantee (registered in Ireland No. 26293) .
> Our registered office is at Whitworth Road, Drumcondra, Dublin 9.
> NCBI is also a registered Charity (chy4626).
>
> NOTICE: The information contained in this email and any attachments
> is confidential and may be privileged. If you are not the intended
> recipient you should not use, disclose, distribute or copy any of
> the content of it or of any attachment; you are requested to notify
> the sender immediately of your receipt of the email and then to
> delete it and any attachments from your system.
>
> NCBI endeavours to ensure that emails and any attachments generated
> by its staff are free from viruses or other contaminants. However,
> it cannot accept any responsibility for any such which are
> transmitted. We therefore recommend you scan all attachments.
>
> Please note that the statements and views expressed in this email
> and any attachments are those of the author and do not necessarily
> represent the views of NCBI
>
>
> ********************************************************************
>
>
>
>
From: Jukka K. Korpela
Date: Thu, Mar 03 2011 1:45PM
Subject: Re: Table SUMMARY Tag
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Joshue O Connor wrote:
> On 02/03/2011 18:09, Jukka K. Korpela wrote:
>> On the other hand, the HTML5 drafts designate the SUMMARY attribute
>> as obsolete and declare that authors must not use it. Whatever we
>> think of HTML5, it seems to be the way the world is going. I guess
>> the reason for making SUMMARY as obsolete is twofold: first, it has
>> fairly limited support and usage; second, it is better replaced by
>> explanations that every user can make use of.
>
> FWIW For the first point, @Summary is very well supported in most
> browsers, it is recognised by most screen reading AT and announced as
> soon as the table is given focus.
I'm not sure whether there is reliable information about support to
different features across AT software and whether we can estimate the impact
(do we know the usage share, worldwide?). But no doubt the summary attribute
is supported to a significant degree - in AT. In normal browsing, the user
does not even notice its existence, and the great majority of users are not
using any AT. This is what I meant by "fairly limited support". And what
about the usage? I don't think the summary attribute is used on more than
perhaps one page out of a thousand.
I must correct a previous statement of mine about the status of the
attribute in HTML5 drafts. The HTML5 terminology is complex and confusing,
and the drafts use different expressions of dislike. The summary attribute
is not forbidden. It is in a small set of "Obsolete but conforming
features", described at
http://www.whatwg.org/specs/web-apps/current-work/multipage/obsolete.html#obsolete-but-conforming-features
So in everyday terms, the drafts don't say that authors must not use the
summary attribute, just that they should not. On the other hand, they do not
require or even recommend that browsers communicate the attribute value to
users; they use the mild word "may": "If a table element has a summary
attribute, the user agent may report the contents of that attribute to the
user."
> For the second, while on paper this looks like a good idea, removing
> @summary from HTML 5 because it couldn't be used by _everybody_
> became a Shibboleth that lost all meaning. @summary content could be
> exposed to sighted users if browsers were wired to do so.
Authors could even now do such things if they wanted to. With a suitable
piece of Javascript code, the summary attribute value could be disclosed on
request. The main problem would be, I guess, the design of the user
interface. How would you convey the idea "there is a description of the
structure or the purpose of this table available"? Someone (maybe me) might
say "Oh, you could just use those words, in a statetement before the table,
with the word "description" turned to a pseudo-link (Javascript-powered).
And this might work up to a point. But many people who would need the
description would not notice it. People don't read web pages that much. If a
table looks messy, they go elsewhere or just get confused.
Anyway, my somewhat naive idea resembles what the HTML5 draft seems to be
saying, more or less. And you can achieve without using a summary attribute.
Just write the explicit text, with a (pseudo) link, perhaps putting some
easy-to-notice icon, symbolizing "help" or "info", adjacent to it. Screen
reader users won't need the icon, so it could have alt="". Screen readers
users would hear, before the table, something like "There is a (link)
description of the structure or the purpose of the following table
available". Simple, isn't it?
> While
> philosophies like Universal Design are great, I would rather see
> elements and attributes that support some user groups very well, than
> elements and attributes that serve all users poorly.
Well I think it partly depends on how poor "poorly" is. But most
importantly, elements and attributes don't really do anything; people do
things with them. And authors - even accessibility-aware authors - don't
seem to have become excited about the summary attribute.
Therefore I think it is more realistic to try to make authors do some effort
in explaining tables, in prose before the table or in its caption or maybe
sometimes elsewhere. They need to learn some new thinking and design
principles, and to apply them, but meaningful use of the summary attribute
would require that, too.
--
Yucca, http://www.cs.tut.fi/~jkorpela/
From: Joshue O Connor
Date: Fri, Mar 04 2011 2:33AM
Subject: Re: Table SUMMARY Tag
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On 03/03/2011 20:02, adam solomon wrote:
> The fact is that extra descriptive information about a table which can really
> help out an AT user, will never be allowed in by a web designer on the basis
> that it is superfluous, and that it does not fit in to their wonderful
> design.
Yes, and with good reason actually.
> So, in effect, we are only hurting the AT user.
Well the @summary is currently conforming but obsolete in HTML 5 but
yes, it is pity to send the wrong signal that there is something wrong
(which is implied by the attributes current status) with using it. The
reality is that support for it in newer user agents is likely to be
disappear (as Gez pointed out a while back), useful or not. [1] [2]
On a positive note, AT like screen readers will adapt to the new spec
and the hope is we will have a progressive forward motion, in terms of a
user experience.
Cheers
Josh
[1] http://www.w3.org/TR/html5/tabular-data.html#attr-table-summary
[2] http://juicystudio.com/article/purpose-of-the-summary-attribute.php
NCBI: Celebrating 80 Years
********************************************************************
National Council for the Blind of Ireland (NCBI) is a company
limited by guarantee (registered in Ireland No. 26293) .
Our registered office is at Whitworth Road, Drumcondra, Dublin 9.
NCBI is also a registered Charity (chy4626).
NOTICE: The information contained in this email and any attachments
is confidential and may be privileged. If you are not the intended
recipient you should not use, disclose, distribute or copy any of
the content of it or of any attachment; you are requested to notify
the sender immediately of your receipt of the email and then to
delete it and any attachments from your system.
NCBI endeavours to ensure that emails and any attachments generated
by its staff are free from viruses or other contaminants. However,
it cannot accept any responsibility for any such which are
transmitted. We therefore recommend you scan all attachments.
Please note that the statements and views expressed in this email
and any attachments are those of the author and do not necessarily
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********************************************************************
From: Joshue O Connor
Date: Fri, Mar 04 2011 2:57AM
Subject: Re: Table SUMMARY Tag
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On 03/03/2011 20:44, Jukka K. Korpela wrote:
> Joshue O Connor wrote:
>
>> On 02/03/2011 18:09, Jukka K. Korpela wrote:
[...]
> I'm not sure whether there is reliable information about support to
> different features across AT software and whether we can estimate the impact
> (do we know the usage share, worldwide?).
No, its hard to get figures. There is such a dearth of this info, or its
fairer to say the figures for usage of A11y related elements/attributes
are so tiny in comparison to the rest (sic) it's easy to conclude that
they are useless. Which they are not. Some indication of use can be
gotten via Dmoz IIRC, or other web trawlers but that's not something I
know a lot about.
[...]
> And what
> about the usage? I don't think the summary attribute is used on more than
> perhaps one page out of a thousand.
Well this is it. And this logic (however correct) signaled its demise,
as such. _But_ where it is useful, and who it is useful for are
important here for a sense of context. My work in the HTML 5 WG to try
and retain it was based on seeing it used in user tests by blind and
visual impaired users. Or it may be more accurate to say *not* seeing it
used and recommending to authors that they add a @summary as it *would*
be useful.
However, often a data table will just need a <caption> element.
Personally, I think @summary is also useful for additional info that may
help the user figure out more info about the table as an 'overview' or
gestalt view but that's not strictly how the spec text defines its
usage. I guess, much of the web is built on the basis that elements are
used and abused in various ways that pushes them beyond their original
design.
[...]
> So in everyday terms, the drafts don't say that authors must not use the
> summary attribute, just that they should not. On the other hand, they do not
> require or even recommend that browsers communicate the attribute value to
> users; they use the mild word "may": "If a table element has a summary
> attribute, the user agent may report the contents of that attribute to the
> user."
Yes.
>> For the second, while on paper this looks like a good idea, removing
>> @summary from HTML 5 because it couldn't be used by _everybody_
>> became a Shibboleth that lost all meaning. @summary content could be
>> exposed to sighted users if browsers were wired to do so.
>
> Authors could even now do such things if they wanted to. With a suitable
> piece of Javascript code, the summary attribute value could be disclosed on
> request.
That's right.
> The main problem would be, I guess, the design of the user
> interface. How would you convey the idea "there is a description of the
> structure or the purpose of this table available"? Someone (maybe me) might
> say "Oh, you could just use those words, in a statetement before the table,
> with the word "description" turned to a pseudo-link (Javascript-powered).
Or you could use a fragment identifier method such as aria-describedby.
> And this might work up to a point. But many people who would need the
> description would not notice it. People don't read web pages that much. If a
> table looks messy, they go elsewhere or just get confused.
Right, and this is why in particular for complex tables, the @summary is
useful.
> Anyway, my somewhat naive idea resembles what the HTML5 draft seems to be
> saying, more or less. And you can achieve without using a summary attribute.
> Just write the explicit text, with a (pseudo) link, perhaps putting some
> easy-to-notice icon, symbolizing "help" or "info", adjacent to it. Screen
> reader users won't need the icon, so it could have alt="". Screen readers
> users would hear, before the table, something like "There is a (link)
> description of the structure or the purpose of the following table
> available". Simple, isn't it?
lol
[..]
> Therefore I think it is more realistic to try to make authors do some effort
> in explaining tables, in prose before the table or in its caption or maybe
> sometimes elsewhere. They need to learn some new thinking and design
> principles, and to apply them, but meaningful use of the summary attribute
> would require that, too.
Yes.
Cheers
Josh
NCBI: Celebrating 80 Years
********************************************************************
National Council for the Blind of Ireland (NCBI) is a company
limited by guarantee (registered in Ireland No. 26293) .
Our registered office is at Whitworth Road, Drumcondra, Dublin 9.
NCBI is also a registered Charity (chy4626).
NOTICE: The information contained in this email and any attachments
is confidential and may be privileged. If you are not the intended
recipient you should not use, disclose, distribute or copy any of
the content of it or of any attachment; you are requested to notify
the sender immediately of your receipt of the email and then to
delete it and any attachments from your system.
NCBI endeavours to ensure that emails and any attachments generated
by its staff are free from viruses or other contaminants. However,
it cannot accept any responsibility for any such which are
transmitted. We therefore recommend you scan all attachments.
Please note that the statements and views expressed in this email
and any attachments are those of the author and do not necessarily
represent the views of NCBI
********************************************************************