Use of the keyboard

Synonyms: keyboard operation, keyboard interface

See also: Use of the pointing device,, fokus indicator, navigation sequence

It must be possible for all functions which can be initialized using a pointing device, motion control or voice input to also be initialized using the keyboard, as disabled users may not be able to use a pointing device and/or may not see the pointer, may not be able to perform the movement or may not be able to speak. It is also possible that disabled users are unable to use a keyboard, but their assistive technology simulates the keyboard and interacts with the keyboard interface of the operating system and/or the Accessibility API.

In this context, the simulation of a pointing device with the keyboard (e.g., keyboard mouse using the numeric keypad) is not considered a permissible alternative form of operation to the use of the pointing device.

Note: The operation of individual elements is described at the respective element.

Note: The use of the keyboard does not generally need to be implemented separately, as it is already made available by the platform software or the framework which is used. Care should be taken to avoid overwriting the keyboard shortcuts for other individual functions, however.

The standard elements of the marking and/or programming language or of the framework used are generally fully keyboard-operable. They should therefore be used with preference.

If custom elements are used, in terms of the keyboard operability, it is necessary to pay attention to the following in particular:

• Accessibility with the keyboard (e.g. using the tabindex),
• Operability with the keyboard (event handler for the keyboard and/or device-independent event handler),
• Operability conforms to the expectations or has been documented (conforms to expectations regarding the visual presentation and the role, that is communicated to the Accessibility API.
• Focus indicator,
• Focus handling (e.g. no loss of focus during operation; Navigation sequence),
• possibly defined keyboard shortcuts are consistent with those of the platform software and/or do not override those of the platform software.

If a custom element is implemented, it is often recommended that a related default element is used and customized accordingly, as it is then possible to use the basic functionality of the default element.

Dragging and dropping elements (drag and drop) can only be done with a pointing device. Designing the alternative form of operation with the keyboard so that it can be used efficiently and in accordance with expectations is recommended. Possible variants include

• Kontextmenü (e.g. for moving elements to other areas),
• several buttons, grouped in one toolbar (e.g. for changing the sequence of elements within an area),
• a button (e.g. for uploading files),
• individual keyboard shortcuts (e.g. adjustment of the size of elements),
• keyboard shortcuts of the platform (e.g. cutting and pasting elements using CTRL+X and CTRL+V),
• use of the arrow keys (e.g. slider),
• Start and finish with the ENTER key, move with the arrow keys (e.g. drawing a freehand screen).

A combination of the variants is often a good idea (e.g. buttons and keyboard shortcuts).

As the alternative form of operation with the keyboard is not usually visible, it should be described in the application and the Help option.

Control elements that are shown and hidden when using the application, e.g.

• because they are in tooltips, or
• because they only appear when the keyboard focus is in a particular position,

are not usually operable with the keyboard.

Displaying control elements all the time and avoiding control elements in tooltips, for example, is recommended.

Alternatively, an alternative form of operation must be implemented using the keyboard and described in the Help option and the application. In addition to this, the application must be designed so that it is perceptible with the assistive technology when elements that are not always visible are shown. Blind users, for example, must be able to perceive that a tooltip contains control elements with the screen reader, so that they can use the documented alternative form of operation with the keyboard.

Information about this article

Date:

21.10.2024

License:

CC-BY-SA 4.0

Version:

1.0

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