Module 4: Checkpoint 2—Logical source order
Form fields must use a logical source order to control tabbing.
Benefits of conformance
- Forms will be easier to maintain and update.
- Improved experience for keyboard and assistive devices (e.g. using tab button).
- Allows universal access (for all users) through support for device independent control.
- Allows for the implementation of 'power users':
- Increased task completion rate.
- Reduction in average handling time for data entry and processing.
Risks of non-conformance
- Discriminates against 'power users':
- Increased average handling time for data entry and processing.
- Increased processing and handling costs.
For individuals using key stroke access (standard 101 keyboards, Intellikeys, onscreen switch activated keyboards and other switch activated alternative key style access) the ability to move through a complex application using the tab key increases accessibility and usability.
The source order of the form controls the order in which the tab key works across the application by default. There are other methods for controlling the tab order of page elements, but following a logical order will reduce the risk of tab order errors being introduced during maintenance.