Bug 81681 – Allow multiple colheads/col and multiple rowheads/row

• Component: Accessibility
• Status: UNCONFIRMED

[Aaron Leventhal]

The current implementation of AXColumnHeaderUIElements and AXRowHeaderUIElements allows only 1 column header per column and 1 row header per row.

There are a number of combinations of markup that would allow more than 1 of a given header type for a row/column.

Caveats:
- this may require changes to the Mac API. If the API is changing anyway, it may be a good time to consider scope="rowgroup" and scope="colgroup", although they are rare.
- it may be a good time to consider the aria-labelledby case where each table cell explicitly indicates which table headers it is labelled by.
- ensure that any code which implements RowHeaderRole and ColumnHeaderRole is also updated to handle multiple headers per col/row.

[Dominic Mazzoni]

I don't think fixing this bug should depend on Mac API changes to be implemented. WebCore should be handling multiple column headers and row headers correctly and then the Mac port should degrade gracefully by, e.g., ignoring all except the first one. If a future version of the Mac a11y API allows for multiple column/row headers, it'd then be easy to implement support - but everything should continue to degrade gracefully on older OS versions.

[chris fleizach]

(In reply to comment #1)
> I don't think fixing this bug should depend on Mac API changes to be implemented. WebCore should be handling multiple column headers and row headers correctly and then the Mac port should degrade gracefully by, e.g., ignoring all except the first one. If a future version of the Mac a11y API allows for multiple column/row headers, it'd then be easy to implement support - but everything should continue to degrade gracefully on older OS versions.

Yes that is true. Anyone can implement this in WebCore

[Radar WebKit Bug Importer]

<rdar://problem/15710220>