2.2 KiB
2.2 KiB
2.5.2 Pointer Cancellation
- Level: A
- Guideline: 2.5 Input Modalities
- Principle: 2 Operable
What it is
For functionality that can be operated using a single pointer, at least one of the following is true:
- No Down-Event: The down-event of the pointer is not used to execute any part of the function;
- Abort or Undo: Completion of the function is on the up-event, and a mechanism is available to abort the function before completion or to undo the function after completion;
- Up Reversal: The up-event reverses any outcome of the preceding down-event;
- Essential: Completing the function on the down-event is essential.
How to test
- Check: The down-event of the pointer is not used to execute any part of the function;
- Check: Completion of the function is on the up-event, and a mechanism is available to abort the function before completion or to undo the function after completion;
- Check: The up-event reverses any outcome of the preceding down-event;
- Check: Completing the function on the down-event is essential.
- Use the sufficient techniques below as acceptable methods when applicable.
- Confirm none of the common failures apply.
Sufficient techniques (W3C)
- G210: Ensuring that drag-and-drop actions can be cancelled
- G212: Using native controls to ensure functionality is triggered on the up-event.
- Touch events are only triggered when touch is removed from a control (Potential future technique)
Common failures (W3C)
- F101: Failure of Success Criterion 2.5.2 due to activating a control on the down-event
Notes
- Note 1: Functions that emulate a keyboard or numeric keypad key press are considered essential.
- Note 2: This requirement applies to web content that interprets pointer actions (i.e., this does not apply to actions that are required to operate the user agent or assistive technology).