On Input

Understanding WCAG2.0

Do not send automatically after you enter all the input fields in the page, or move the page if you check the check boxes and radio buttons.

Sometimes there is an interface that moves pages in response to select onchange. For the user operating the mouse, the third item can be selected, but in the case of the keyboard, onchange determination is made as soon as the down key is pressed, and never downward by two It can happen that you can not go (in some sense it's a "keyboard trap"). In such a case, you will need to give "execute button".

This Success Criterion is similar to 3.2.1, except that it may be allowed if the change in the situation is predictable and controllable (In the case of focus, prediction and control are inherently difficult). For example, when there is a form to add a schedule to the calendar, it is predictable and controllable that the entry field dynamically changes when you select a schedule type with a radio button.

Also, when entering 4 digits of credit card number etc., behaviors that automatically focus on the next field when 4 characters are input are permitted if explained beforehand.

Principle Understandable Information and the operation of user interface must be understandable.
Guideline Predictable Make Web pages appear and operate in predictable ways.
Criterion On Input
(3.2.2 A)
Changing the setting of the user interface component does not automatically cause a context change. However, unless the user informs the behavior before using it.

URL of Techniques for WCAG 2.0