SIA-R46All table header cells have assigned data cells
This rule tests conformance of the following accessibility requirements:
This rule checks that each table header has assigned data cells in a table element.
- the element has a semantic role of
- the element is visible; and
- the element is included in the accessibility tree; and
- the element has at least one ancestor in the flat tree which is a
- the element's closest
<table>ancestor is included in the accessibility tree.
This rule makes the following assumption:
- Table header cells have a relationship conveyed through presentation with other cells within the same table.
This rule has the following accessibility support concern:
- Table markup and header cell association is not well supported by some popular assistive technologies.
When deciding whether a
<th> whose scope attribute is in the
auto state is a column header or row header, empty data cells are ignored by this rule. This in turn impacts header assignment, since these cells may now be assigned as headers. Most User Agents and Assistive Technologies likewise ignore empty data cells. It is a common practice to have an empty data cell in the top-left corner of tables with both columns and rows headers.
This document includes material copied from or derived from https://act-rules.github.io/rules/d0f69e/. Copyright © 2021 W3C® (MIT, ERCIM, Keio, Beihang).