1.8 Ensure that equivalents for dynamic content are updated when the dynamic content changes
Contents
WAI checkpoint 6.2
Full WAI text: "Ensure that equivalents for dynamic content are updated when the dynamic content changes."
Dynamic content is information which is updated in real time or which changes every time it is accessed. It could be text content which is held on a database and is presented to the user as it 'comes live' and is then uploaded in real time to a web page. Video, audio and content presented through scripts and applets is also dynamic. A continually scrolling news ticker, presented through a script or applet, is dynamic if the headlines are updated in real time.
Information presented in dynamic features must also be repeated in an equally up to date equivalent version.
Rationale
Many methods for delivering dynamic content rely on newer technologies which may be inaccessible to users of older equipment.
Some methods cause problems for users with limited mobility, reading difficulties or poor sight. This can happen when dynamic content changes continually or automatically refreshes in only one area of a web page, e.g. a scrolling news ticker. This type of presentation causes problems for screen readers. Users with limited mobility may find it difficult to click on the moving links. Users with poor sight or reading difficulties find it difficult to read moving text.
Frames are another method, often used to present dynamic content. Frames are used to divide the page into sections. For example, the left hand side of a web page could present navigation links in one frame (the navigation frame), while the main content is presented in another (the content frame). The navigation frame always presents the same content but the information in the content frame is dynamic because it changes depending on the link selected from the navigation frame.
If these methods are used to present dynamic information, it is good practice to provide an equivalent version, possibly on another page. However, this version must be as timely and up to date as the dynamic version. If it isn't, users will be misinformed.
Directions and Techniques
Provide text equivalents for applets and programmatic objects
Follow the WAI recommended techniques for providing WAI recommended techniques for providing equivalents of content and functionality presented through applets and other programmatic objects
Provide text equivalents of frames
Frame contents and the relationships between frames should make sense. Follow WAI recommendations for providing text equivalents of frames
Provide text equivalents of scripts
Follow WAI recommended techniques for providing equivalents of content and functionality presented through scripts.
How you could check for this:
There are no specific test methods recommended for this guideline.
Guidelines for Web Accessibility - Priority 1- 1.1 Provide a text equivalent for every non-text element
- 1.2 Ensure that information does not rely on colour perception
- 1.3 Avoid causing the screen to flicker
- 1.4 Provide an auditory description of the visual information in multimedia presentations
- 1.5 For multimedia, ensure that timing of alternative descriptions is synchronised with the presentation
- 1.6 Use the clearest and simplest language appropriate
- 1.7 Identify language changes in text
- 1.8 Ensure that equivalents for dynamic content are updated when the dynamic content changes
- 1.9 For data tables, identify row and column headers
- 1.10 For complex data tables, use mark-up to associate data cells and header cells
- 1.11 Add titles to frames
- 1.12 Ensure that documents can be read without style sheets
- 1.13 Provide text links to emulate server-side image maps
- 1.14 Use client-side image maps rather than server-side image maps where possible
- 1.15 Ensure that scripts and applets that provide the only source of important functionality are directly accessible or compatib
- 1.16 Ensure that pages are usable without support for scripts, applets, or other programmatic objects
- 1.17 If you cannot make a page accessible, provide an equivalent accessible page
