Design Pattern: Let Users Control When the Content Moves or Changes
User Need
I need to know where things are. Controls and content do not move unexpectedly as I am using them.
What to Do
Ensure that changes of context, functionality, settings, route, and orientation are initiated only by user request or an easily available mechanism is available to turn off such changes. Also provide an easily available mechanism to go to previous context, functionality, settings, route, and orientation.
How it Helps
Any content, settings, or functionality which changes unexpectedly, without user initiation can result in significant problems for users with cognitive and learning disabilities. Unexpected changes in any of these areas can result in loss of focus, anxiety, or confusion in understanding or using a user interface (such as menus, buttons, and design components). Examples include, but are not limited to:
- The automatic launching of new windows or pop-ups.
- Submission of forms through mechanisms other than a button that is clearly labeled (using simple language to submit the form).
- The opening of new content or a feature.
- Unexpected changes when selecting an option.
- Rerouting automatically by a Global Positioning System (GPS).
- Changing the direction of a map in a GPS.
For example, a user may not have a sense of direction or know their left and right. Before using a GPS, they may study the route so that they know approximately what they are doing and can augment the directions of the GPS with their own context, using the GPS for cues. The GPS automatically reroutes them because of a small traffic delay. They become completely lost and disoriented and can no longer use the application.
In another example, a user is watching a video and wants to press “like”. As they are about to press the button, the controls shift and they load a different video instead of pressing “like”. They are now less likely to press “like” because they do not want to lose their content. As a result, their preferences are not taken into account.
Letting users control when content changes gives users with cognitive and learning disabilities more control over how web sites and applications behave. This gives them the opportunity to make choices that enable them to use the content and complete the task.
More Details
Exception: The changes are part of an activity where it is essential (e.g. a game).
Route: This is the directions and flow such as a GPS route.
Orientation: perspective or view such as map direction.
Easily available (or easily available mode or setting), is when one or more of the following is true:
- It can be set one time with as a wide a scope as possible (such as using the standards of the Operating System (OS), From [[ISO 9241-112]] or [[GPII]] when available).
- It has the option to save or to change the setting for the scope of the set of web pages.
- It is reachable from each screen where it may be needed, and the path and the control conforms to all of this document.
Examples
Use:
-
User control when content changes. For example:
- The user can set to change the route if more than a specific amount of time is saved. They can add more information such as how many extra turns are acceptable for saving 5 minutes. When the GPS finds a new route that saves time, the GPS tells the user about the change including how many extra turns were added and how much time will be saved. The GPS asks the user if they want to change the route or if the GPS changed it, the user can go back to the original route in one touch or command.
Avoid:
- Content that changes without the user having control.