Basic Principles of Accessible Design
Accessible design is important to you and your organization because it enables you to reach more customers in business, government, and education that need to comply with new regulations requiring purchase of accessible applications. Accessible design is also a requirement of the Certified for Windows logo; the logo handbook about this program currently lists five requirements designed to make applications more accessible:
- Support standard system size, color, font, and input settings. This provides a consistent user interface (UI) across all applications on the user's system.
- Ensure compatibility with the High Contrast option. Users desiring a high degree of legibility select the High Contrast option. When this option is selected several restrictions are imposed upon the application. For example, only system colors selectable through Control Panel or colors set by the user may be used by the application.
- Provide documented keyboard access to all features. This allows the user to interact with the application without requiring a pointing device, such as a mouse.
- Provide notification of the keyboard focus location. It should always be apparent both to the user and programmatically which part of the application has the focus. This requirement also enables use of the Magnifier and Narrator accessibility aids.
- Convey no information by sound alone. Applications that convey information by sound must provide other options to express this information.
Developers can make applications accessible by offering built-in options and by making the user interface familiar and consistent.
There are five basic principles underlying the idea of accessible design:
- Flexibility. Provide your customers with a flexible, customizable user interface that accommodates a variety of user needs and preferences.
- Choice of input methods. Provide users with keyboard access to all features and simple mouse click access for common tasks.
- Choice of output methods. Provide users with the ability to choose discrete and redundant output combinations of sound, visuals, text, and graphics.
- Consistency. Make your applications interact with other applications and system standards in a consistent, predictable manner.
- Compatibility with accessibility aids. Whenever possible, build your applications using standard and common user interface elements that are compatible with accessibility aids.
For more information, see Windows 2000 Logo Certification (http://msdn.microsoft.com/certification/default.asp).