Re: function and impacts (was: @scope and @headers reform)

Gez wrote,

> Whether there is a way to mark this up accessibly or not, this is
> typical of the view a user wants of the data. At the moment, we
> recommend using the headers attribute, but the new restrictions on
> HTML5 (the headers attribute can't reference a td, and a td can't
> contain a scope attribute) means that the headers attribute is pretty
> much useless in HTML5 without allowing nested headers (which isn't
> currently allowed in the specification). With the current restrictions
> on the headers attribute, it's difficult to imagine a scenario where
> the headers attribute can actually be used.

Yes, the way it is specified in HTML 5 only allows the simplest of
data tables to be defined accessibly, which defeats the purpose of
getting the headers attribute into the specification at all, because
it can't do anything that most ATs don't already do by default.
Currently implementation is such that complex tables cannot be created
using the headers attribute. The language in the current spec is
attempting to pacify PFWG. The spec complies with PFWG's advice by
paying lip service to headers while dissenting in functional
requirements. It is an attempt to circumvent the issue not solve it.
The headers attribute in the current specification is of little use,
as it can only reference a th, and the th cannot be a hierarchical th.
Without being able to associate header cells to data cells, screen
reader users will either have great difficulty, or find it impossible,
to orientate themselves in complex data tables.

As hierarchical headers are not allowed in HTML5, this means that
conceptual headers (cells that contain data and have their own header,
but act as a header for other cells in the table) must be marked up as
a td. As these cells are conceptually headings, the headers attribute
should be able to reference the id attribute of these cells.

> If HTML5 allows
> aria-labelledby on table cells, I would be in favour of dropping the
> headers attribute completely, as it can't be used practically, and use
> aria-labelledby for complex associations instead.

This is an interesting proposal and perhaps a way forward.

The question is will aria-labelledby on table cells be written into
the html5 spec?

Best Regards,

Laura L. Carlson

Received on Tuesday, 23 September 2008 11:30:31 UTC