Navigability, part 1:
The General Use Case
- Need:
- Ability to navigate within sub-components of documents containing specialized content
examples: math, music, genomic or chemical markup
- Why an Expert Handler?
- 1. AT doesn't know how to deal with specialized content directly;
- 2. specialized components have content which needs to receive focus at different levels of granularity; for example a numerator within a numerator, an expression, a term, a bar of music, etc.
- How?
- Each level of granularity needs to be able to provide the AT commands to inspect and navigate to and from "items" -- by word, bar, expression, clause, term, etc. -- depending upon the type of content being expressed.
- Three system components need to interact:
- 1) the user agent or editor,
- 2) the AT, and
- 3) the expert handler