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Re: data or layout table

for

From: Jared Smith
Date: Sep 2, 2011 1:27PM

On Fri, Sep 2, 2011 at 12:42 PM, John Foliot wrote:

> However, if we had 3 cells:
>
>        <td><img></td>  <td><a href></a></td>  <td>info</td> - especially
> if they are in subsequent rows
>
> ...then adding TH's would be critical for comprehension.

Not necessarily. The table headers aren't vital in this situation
either because the content is no less comprehensible than if it were
outside a table. If the screen reader just reads through the content
in order, it makes sense. As Deborah indicated, it's not really data
being presented - it's just linear information with borders around
them. Headers would add unnecessary overhead.

As you note, CSS to control this presentation would be better, but
would read no different and be no more or less accessible than if it
were in a layout table (so long as you don't complicate things by
adding table headers).

But what if there were 10 items per row instead of 3? Then this is
starting to look more like data than presentation and headers would
probably help. You might ask, "Is it likely that the user would want
or need to navigate up and down through columns?" If so, it's probably
data and should have headers. Yes, I realize this is not well defined.

Now if the layout were:

<tr>
<td><img></td> <td><img></td> <td><img></td>
</tr>
<tr>
<td><a href></a></td> <td><a href></a></td> <td><a href></a></td>
</tr>
etc.

... this would be confusing if read linearly in a layout table,
especially if there were more than a few columns or rows. And there
would be no easy way to navigate the table columns to determine which
image goes with which link, etc. In this case, headers would be
necessary.

This is certainly one of those fuzzy areas of accessibility.

<plug type=shamless>
I'll be speaking on these types of things at the Accessibility Summit
later this month -
http://environmentsforhumans.com/2011/accessibility-summit/
You can also vote today for a SXSW proposal I have on this topic -
http://panelpicker.sxsw.com/ideas/view/12184
</plug>

Jared