When any component receives focus, it does not initiate a change of context.
Someone navigating a Web page with a screen reader can not understand the site if there is a change of context when an object gets focus. The user should be able to predict the circumstances that trigger a change of context. Just the act of receiving focus must not cause a change of context. The WCAG 2.0 Working group provides the following examples of context changes that are not accessible:
Note that a change of content is not always a change of context. This checkpoint is automatically met if changes in content are not also changes of context.
To comply with this checkpoint, you must meet the following technique.
This technique is defined in WCAG 2.0 Level A Success Criterion 3.2.1 (link resides outside of ibm.com).
Triggers for changes of context: Use "activate" rather than "focus" as a trigger for changes of context.
Note: The examples presented in the techniques are not exhaustive. They are meant to illustrate the spirit of this checkpoint.
To comply with this technique, you must implement the following example.
General example 1
A new page is not loaded, unless the user takes an overt action to reload the page. Simply tabbing to an area of a page must not cause the page to reload or cause a new page to load, unless the user activates a control with a button.
For additional information, refer to the WCAG 2.0 examples of using "activate" rather than "focus" as a trigger for changes of context (link resides outside of ibm.com).
General example 2
Do not use scripts to remove focus when focus is received. Refer to the example in Checkpoint 2.1b: Scripts.
Required unit tests for general development technique 1
Manually perform the following unit tests.
Although you do not have to implement the recommended techniques in order to comply with this checkpoint, you should review them since they can improve the accessibility and usability of the application.
Refer to the WCAG 2.0 Additional Techniques (Advisory) for 3.2.2 (link resides outside of ibm.com). Use of these techniques goes beyond compliance to making the Web site usable, as well as accessible.
Copyright 2012, 2013 IBM Corporation
Last updated February 1, 2012.
W3C Recommendation 11 December 2008:
(link resides outside of ibm.com)
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