RE: Table Techniques - Summary

If we allow the non-use of the summary attribute we are, IMHO, informing
designers that it is not important.  The summary is just as important as
the alt.

As I've pointed out many times previously, a machine tester can validate
a null summary and ensure that there are no captions and th elements
used.  The non-use of the summary attribute then makes the machine test
invalid because the machine would have no idea whether the table is for
layout or tabular information.

A summary with text can only be validated for the inclusion of text.  It
wouldn't be easy to validate for the content of the summary attribute.

For example, in English the term layout would have to translated and
understood by the machine tester if we allowed content in the summary
attribute.  How many languages are there?  Would the machine tester have
to know each translation?

Therefore, it is much easier to machine test for a null summary than
content that would otherwise indicate the table is used for a layout.

And again, the lack of a summary would lead designers to think that the
summary attribute is not important.  Hence, the null summary provides
valuable information.

My recommendation is to require a null summary for layout tables.

Lee

-----Original Message-----
From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On
Behalf Of Roberto Scano - IWA/HWG
Sent: Thursday, August 14, 2003 3:56 PM
To: John M Slatin; Matt May; Chris Ridpath
Cc: WAI WCAG List
Subject: Re: Table Techniques - Summary




----- Original Message ----- 
From: "John M Slatin" <john_slatin@austin.utexas.edu>
To: "Matt May" <mcmay@w3.org>; "Chris Ridpath"
<chris.ridpath@utoronto.ca>
Cc: "WAI WCAG List" <w3c-wai-gl@w3.org>
Sent: Thursday, August 14, 2003 9:43 PM
Subject: RE: Table Techniques - Summary


>
> I agree that null summary (summary="") should be allowed for layout 
> tables.  As Matt points out, this indicates a postive intention on the

> author's part to force screen reader behavior, just as the null alt 
> attribute for images does.  Use of the <th> element is *another* good 
> indicator of the author's intent, in this case to create a data table 
> rather than a layout table.
>
> By contrast, the absence of a summary attribute, like the absence of 
> an alt attribute, may simply indicate ignorance or indifference on the

> author's part.

I could understand and agree with John but the HTML reference [1]
referring to "summary" explain that:

"This attribute provides a summary of the table's purpose and structure
for user agents rendering to non-visual media such as speech and
Braille."

"summary" is different from the ALT attribute [2] that must be specified
for the IMG and AREA elements.

So, if there is no text that presents the table's purpose and structure,
why use the attribute?

Roberto Scano
---
[1] http://www.w3.org/TR/html401/struct/tables.html#adef-summary
[2] http://www.w3.org/TR/html401/struct/objects.html#adef-alt

Received on Friday, 15 August 2003 09:58:52 UTC