The new Articles panel and InDesign's new methods for mapping styles to PDF tags let you ensure content flows in the expected order when viewers use screen readers and other assistive technologies.
In previous releases, InDesign would export all block level text to a <p> tag and use CSS to create the visual presentation. A downside to this approach is that 3rd party applications could NOT infer any “semantic” meaning. For example, 3rd party accessibility readers could NOT read aloud text as a “heading” and EPUB readers with no support for CSS would present everything as a generic paragraph, since they could not find any “headings” in the code.
Users who needed more semantic markup had to use one or more of the following workarounds:
- Use some kind of post-processing scripts
- Edit the code by hand
- Purchase a 3rd party plug-in
- Use the Structure Pane > Map Styles to Tags feature.
All of these workarounds required significant effort and investment to the average user. Because the mapping is now integrated within the Paragraph and Character Styles, it persists even as the INDD file is continually edited and revised. Users can also take advantage of other traditional features such as loading styles from other documents and using “Based on Style” to cascade the defined tag to subsequent styles. There is no need to use the Structure Pane features and no need to create the tags in the Tags panel.
The traditional Paragraph and Character Style dialogs have a new sub-feature—“Export Tagging”. Export Tagging provides the means of defining how text with InDesign Styles should be marked up when exported to either HTML/EPUB or tagged PDF.
“Edit All Export Tags” is a new command accessible from both Paragraph Styles and Character Styles flyout menus. This command displays a list of style names and provides ability to view and edit all mappings (EPUB/HTML, and PDF) - class names (EPUB/HTML only).
This represents a significant time savings when compared to clicking on each Paragraph Style individually to specify Export Tagging for each paragraph style. Please note that Tagged PDF does not support any character level tagging.
There is no need to map Paragraph Styles used for bullets or numbered lists or tables. InDesign automatically assigns the right tags upon exporting to tagged PDF, as long as InDesign-specific features for lists and tables are used, rather than manually created to give the “look” (for example, manually inserting a tab stop).