Make it easier for users to interact with added content. Tooltips, drop-down menus, and popups are examples of added content. This new content is usually made visible when you put your mouse pointer over a "trigger" item such as a button or link. It can also display when an item receives focus. Some people have difficulty keeping the mouse pointer over the trigger item. Also, the new content will sometimes obscure existing content. The three requirements of this success criterion, as outlined below, help make the added content more operable.
If keyboard shortcuts are implemented using only a letter (including upper- and lower-case letters), punctuation, number, or symbol characters, provide a way to turn off or remap character key shortcuts:
Turn off: A mechanism is available to turn the shortcut off;
Remap: A mechanism is available to remap the shortcut to use one or more non-printable keyboard characters (e.g. Ctrl, Alt, etc);
Active only on focus: The keyboard shortcut for a user interface component is only active when...
Modal dialogs can enhance usability by focusing attention on a specific message that requires a user action to continue.
Expandables (sometimes called “collapsible” or “disclosure widgets”) are simple interface patterns that allow you to expand and collapse content. They can be helpful accessibility aids as they give users the choice of revealing content to read it, or bypassing the content, making page navigation more efficient for screen-reader users and people using the keyboard or alternative input devices.
To ensure that they are accessible, it's important that expandable sections are coded so that their state (...
Interactive elements should, under most circumstances, be focusable in the order that they appear in the source code. This helps people who are using the keyboard or alternative input devices to follow focus in a logical order.
The order that elements appear in the document source should reflect the order they appear visually.
Visually indicating which element has focus is important for effective keyboard navigation. It's also important to ensure that only those elements that are available visually for interaction are focusable. If an active element is intended to be unavailable in a particular state and it’s hidden from view, it should not be able to receive focus.
Having to tab through invisible controls to reach visible ones is arduous and potentially confusing for sighted users navigating the page by keyboard. Also, screen-...
Links (<a> elements) are focusable by default, so it should normally be possible to activate them using the keyboard. However, under certain circumstances, they are not focusable: Unless you are deliberately trying to "disable" a link, make sure it does not take the form of any of these examples.