When a user is interacting with a component on our page we want them to know what to expect. If they change the setting of a component and something drastic changes, like their focus, it can be very disorienting, especially for those users who do not easily perceive the change or are easily distracted by changes. A user will expect this when triggering a button or link but not when changing the value of a form field.
- Changing focus or large pieces of content when a user changes the value of a form field should be avoided. When it is necessary the user should be warned in advance.
- Triggering a link or submitting a form are exempt from this standard.
- Focus should not advance to the next input in a form automatically unless the user is warned in advance.
- Examples of user input are checking a checkbox, entering text into a text field, or changing the selected option in a list control.