Purpose and Implementation of Guideline 2.4: How the guideline clearly identifies
goals and enhances developer freedom
Guideline 2.4 Provide ways to help users with disabilities navigate, find
content and determine where they are Understanding
Guideline 2.4
- Focus is on removal of an operability barrier: Users with disabilities
need the same random access as all other users
- Compare to
Guideline 13. Provide
clear navigation mechanisms.
- 2.0 Guideline 2.4 focuses on necessary operability barrier removal while
1.0 Guideline focuses on mechanisms that fix some barriers.
- The difference is precision and freedom. 2.4 is clear about capabilities
users with disabilities must have and gives the developer many ways to address
the issue.
2.4.1 Bypass Blocks: A mechanism is available to bypass blocks
of content that are repeated on multiple Web
pages. (Level A)
- Operational Function : Page skimming for users with reading disabilities
and inability to use the mouse
- Repetitive content is visually obvious, and page authors provide visual
cues to make repetitive content stand out. The mouse can then be pointed
and clicked to bypass these sections.
- This criteria requires document cues and traversal operations that do
not require visual reading or a mouse
- This can be implemented in many ways
- Document outline organized using heading elements.
- Table of contents using links.
- Chains of skip-links that go from section to section.
- Authors are given many choices among techniques to satisfy 2.4.1.
- Note that the document outline approach using heading elements almost guarantees
satisfaction of the heading requirement for, " 2.4.6 Labels
Descriptive: Headings
and labels are
descriptive. (Level AA)".
2.4.2 Page Titled: Web
pages have descriptive titles. (Level A)
- Operational function : Isolating the text that identifies the purpose of
the page from all other page content.
- The visual organization of a good page directs unimpaired users to the
main content and its heading.
- The <title> element within the <head> element posts this information
in a uniform location, outside of the page. This can be located by sighted
users with limited ability to scan for specific content, and it can be read
by screen readers. The method for success is simple. Use the <title> element
to describe the page.
- With the page title posted outside of the page content, developers are
free to use page real estate for content not identification.
2.4.3 Focus Order: If a Web
page can be navigated
sequentially, focusable components receive focus in an order that follows
information and relationships conveyed through presentation.
(Level A)
- Operational function: Traversing the page in visual reading order without
using sight or a mouse.
- Users with sight can detect the page order visually and mouse users can
use scroll bars to move through pages.
- Some techniques
- Place active elements in the HTML content in the page reading order
- Create a logical tabbing order for links, forms and objects
that follows the logical order of the page
- Avoid tab indexing operations that disrupt this order.
2.4.4 is not certain.