All technologies that support interactive operation.
This technique relates to Success Criterion 2.1.1: Keyboard (Sufficient).
The objective of this technique is to provide keyboard operation for all the functionality of the page. When all functionality of content can be operated through a keyboard or keyboard interface, it can be operated by those with no vision as well as by those who must use alternate keyboards or input devices that act as keyboard emulators like speech input software or on-screen keyboards.
A keyboard interface allows users to provide keystroke input to programs even if the computing device that they are using does not contain a hardware keyboard. For example, many mobile devices have keyboard interfaces within their operating system as well the option to connect external wireless keyboards. Applications can use the interface to obtain keyboard input either from an external keyboard or from other services that provide simulated keyboard output, such as switch devices, handwriting interpreters or speech-to-text applications.
To implement this technique, first determine what functionality is available to users on the page. In this step, it is important to consider functions performed using both the mouse and the keyboard together. Examples of functionality include the use of physical controls such as links, menus, buttons, checkboxes, radio buttons and form fields as well as the use of features like drag and drop, selecting text, resizing regions or bringing up context menus. Other examples of functionality may based on tasks such as adding or removing an item from a shopping cart or initiating a chat session with a sales representative.
Once the functionality of the content has been determined, the author verifies that each of the functions identified can be performed using only the keyboard.
This does not necessarily mean that each of the individual controls can be used from the keyboard as long as there are multiple methods to perform the same function available on the page. Authors are advised to consider how users will discover any keyboard equivalents which are available.
- A page with images used as links changes when the user hovers over the image with a mouse. To provide keyboard users with a similar experience, the image is also changed when a user tabs to it.
- A page that allows users to click and drag items in a list to reorder them also includes a series of controls that allows keyboard users to move items up, down or to the beginning and end of the list.
- The mobile version of a web site includes a menu button that is tapped to open a site menu, which is implemented as a floating overlay. To provide access to people using external keyboards or ability switches with their mobile device, the menu button and the site menu are both implemented such that they can be operated via the mobile device's keyboard interface.
- Identify all functionality on the content.
- Check that all functionality can be accessed using only the keyboard or keyboard interface.
- Check #2 is true.