On Focus:
Understanding SC 3.2.1
3.2.1 On Focus: When any component receives focus, it does not initiate a change of context. (Level A)
Intent of this Success Criterion
The intent of this Success Criterion is to ensure that functionality is predictable as visitors navigate their way through a document. Any component that is able to trigger an event when it receives focus must not change the context. Examples of changing context when a component receives focus include, but are not limited to:
forms submitted automatically when a component receives focus;
new windows launched when a component receives focus;
focus is changed to another component when that component receives focus;
Specific Benefits of Success Criterion 3.2.1:
This Success Criterion helps people with visual disabilities, cognitive limitations, and motor impairments by reducing the chance that a change of context will occur unexpectedly.
Examples of Success Criterion 3.2.1
Example 1: A dropdown menu
A dropdown menu on a page allows users to choose between jump destinations. If the person uses the keyboard to move down to a choice and activates it (with a spacebar or enter key) it will jump to a new page. However, if the person moves down to a choice and either hits the escape or the tab key to move out of the pulldown menu – it does not jump to a new screen as the focus shifts out of the dropdown menu.
Example of a Failure: A help dialog
When a field receives focus, a help dialog describing the field opens. As a keyboard user tabs through the Web page, the dialog opens every time the user attempts to tab past the field.
Techniques and Failures for Success Criterion 3.2.1 - On Focus
Each numbered item in this section represents a technique or combination of techniques that the WCAG Working Group deems sufficient for meeting this Success Criterion. The techniques listed only satisfy the Success Criterion if all of the WCAG 2.0 conformance requirements have been met.
Sufficient Techniques
Additional Techniques (Advisory) for 3.2.1
Although not required for conformance, the following additional techniques should be considered in order to make content more accessible. Not all techniques can be used or would be effective in all situations.
Not causing persistent changes of state or value when a component receives focus, or providing an alternate means to reset any changes (future link)
Failures for SC 3.2.1
The following are common mistakes that are considered failures of Success Criterion 3.2.1 by the WCAG Working Group.
Key Terms
- changes of context
change of:
focus;
Note: A change of content is not always a change of context. Small changes in content, such as an expanding outline or dynamic menu, do not change the context.
Example: Submitting a form, opening a new window, or moving focus to a different component are examples of changes of context.