2.5.2 Pointer Cancellation Level A

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.

*Functions that emulate a keyboard or numeric keypad key press are considered essential.
*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).

[View on W3C.org]

Testing & Remediation

How to test:
  • No down-event - check the functionalities of your site or app to ensure that interactivity does not happen upon down-event (the push down action of a mouse click or a tap). Activation should only happen on the up-event action (releasing of the mouse click or a tap).
  • Up-event abort or undo - when an action is initiated by an up-event, ensure the user has a way to abort or undo. For example - when you are able to drag & drop an item, once the item is dropped the user gets a prompt to undo.
  • Up reversal - with interactions where the down-event triggers a behavior, ensure that the up-event reverses the action. For example - press-and-hold actions such as where a transient popup appears (or a video plays) when the user presses on an object (down-event), but the popup (or video) disappears as soon as the user releases the pointer (up-event). Since the up-event reverses the preceding down event, the user is returned to their prior point, and has effectively cancelled the operation.
For content that is draggable, check whether the drag-and-drop action can be reversed by:
  1. releasing the picked-up item outside a drop target
  2. dragging the picked-up item back to its old position
  3. a confirmation dialog or an undo control appears after the item has been dropped
How to remediate: There are numerous ways to fix issues related to this success criteria that will depend upon the type of functionality your site/app has. At a high level:
  • Ensure that drag & drop actions can be cancelled
  • Match the accessible name to the visible label
  • Touch events are only triggered when touch is removed from a control

Questions and Answers