Understanding WCAG 2.0

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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:

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Focus may be moved to a control either via the keyboard (e.g. tabbing to a control) or the mouse ([begin change]e.g.[end change] clicking on a text field). Moving the mouse over a control does not move the focus unless scripting implements this behavior. Note that for some types of controls, clicking on a control may also activate the control ([begin change]e.g.[end change] button), which may, in turn, initiate a change in context.

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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

Related Resources

Resources are for information purposes only, no endorsement implied.

(none currently documented)

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

  1. G107: Using "activate" rather than "focus" as a trigger for changes of context

Note: A change of content is not always a change of context. This success criterion is automatically met if changes in content are not also changes of context.

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.

Key Terms

changes of context

major changes in the content of the Web page that, if made without user awareness, can disorient users who are not able to view the entire page simultaneously

Changes in context include changes of:

  1. user agent;

  2. viewport;

  3. focus;

  4. content that changes the meaning of the Web page.

Note: A change of content is not always a change of context. Changes in content, such as an expanding outline, dynamic menu, or a tab control do not necessarily change the context, unless they also change one of the above (e.g., focus).

Example: Opening a new window, moving focus to a different component, going to a new page (including anything that would look to a user as if they had moved to a new page) or significantly re-arranging the content of a page are examples of changes of context.