css

Page 307

Aural style sheets

A.11.1 Speaking headers: the ’speak-header’ property ’speak-header’ Value: Initial: Applies to: Inherited: Percentages: Media: Computed value:

once | always | inherit once elements that have table header information yes N/A aural as specified

This property specifies whether table headers are spoken before every cell, or only before a cell when that cell is associated with a different header than the previous cell. Values have the following meanings: once The header is spoken one time, before a series of cells. always The header is spoken before every pertinent cell. Each document language may have different mechanisms that allow authors to specify headers. For example, in HTML 4 ([HTML4]), it is possible to specify header information with three different attributes ("headers", "scope", and "axis"), and the specification gives an algorithm for determining header information when these attributes have not been specified.

Image of a table with header cells ("San Jose" and "Seattle") that are not in the same column or row as the data they apply to. This HTML example presents the money spent on meals, hotels and transport in two locations (San Jose and Seattle) for successive days. Conceptually, you can think of the table in terms of an n-dimensional space. The headers of this space are: location, day, category and subtotal. Some cells define marks along an axis while

4 Sep 2009 15:30

307


Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.