Technique G219:Ensuring that an alternative is available for dragging movements that operate on content
Applicability
Content using any technology which supports pointer input.
This technique is not referenced from any Understanding document.
Description
The objective of this Technique is to ensure that people with motor impairments who cannot carry out dragging movements are presented with an alternative single pointer interaction that does not involve dragging.
Some direct manipulation interfaces allow users to pick up targets and use dragging movements to move them to another position, for example, to change the position of an item in a priority list, or to move a task on a Kanban or planning board.
Such dragging movements are difficult or impossible to carry out for some users with motor disabilities. The alternative to dragging movements operates the underlying function by one or several single pointer activations that don't require dragging. A single tap or click may reveal controls (arrows) to move a target in a stepwise fashion; open a drop-down menu where the drop position can be selected; or allow moving it to an ajacent postion by a swipe gesture.
Examples
Example 1
- A list of items can be re-ordered by picking up an item and dragging it upwards or downwards. Other elements move dynamically to open a gap where the picked-up target can be dropped. After a single pointer activation, the list items display up and down arrows which allow a step-wise re-ordering of the list via single pointer inputs (taps or clicks at the up or down arrow).
- A vertical priority list indicates the priority of items listed. Each item can be ‘picked up’ with a pointer and dragged up or down to another position. The other list items rearrange dynamically. To the left of each list item, a number in a text field shows the current priority position. For any of the items, users can put in another number. This leads to a dynamic reordering and renumbering of the priority list.
- In a Kanban implementation for process management, tasks can be dragged horizontally from one ‘swimming lane’ to another in order to change the status of tasks (for example, to change the status of a task from “in process” to “completed”). One or several items in a lane can be selected by a single tap or click. A single pointer activation of a drop-down menu labelled “Move selected items to” offers a selection of drop targets (other lanes). A further single pointer activation over the desired menu item moves targets to the specified lane.
- In a radial control widget, the visual indicator of the current value of the control can be dragged to a different position. Users can also click or tap on another position of the radial control to change the value.
Tests
Procedure
For interface elements that support dragging:
- Check the interface for the presence of functions triggered by dragging movements.
- Check that there is a single pointer activation alternative that does not require dragging to operate the same function
Expected Results
- Check #2 is true.
If this is a sufficient technique for a success criterion, failing this test procedure does not necessarily mean that the success criterion has not been satisfied in some other way, only that this technique has not been successfully implemented and cannot be used to claim conformance.