Software checklist

Checkpoint 4.4: Variety of color selections

When color customization is supported, provide a variety of color selections capable of producing a range of contrast levels.


Rationale

When software enables users to customize colors, this checkpoint requires the software to provide more than just a variety of color choices. The color choices must provide different levels of contrast. Someone with low vision needs high contrast between text and the background to read information on the screen. Someone with another vision impairment may be sensitive to bright displays and cannot focus on a bright screen. They would need color choices that provide a softer background and appropriate foreground color. Because there are a wide variety of needs, software that supports color customization must provide a variety of color and contrast settings.

Note: This checkpoint does not apply to software that does not provide an option for users to adjust screen colors.


Required development techniques


The following techniques are the minimum required to meet Checkpoint 4.4 from the IBM Software Accessibility Checklist:

  1. If custom color is supported in your application, then you must provide at least three color choices that offer sufficient contrast.

Examples for Microsoft Windows developers

1. If custom color is supported in your application, then you must provide at least three color choices that offer sufficient contrast.

Example 1

The application can increase legibility for some users by heightening screen contrast with alternative color combinations. Examples of contrasting color combinations are black on white, white on navy, and yellow on blue.

Examples for Eclipse SWT developers

1. If custom color is supported in your application, then you must provide at least three color choices that offer sufficient contrast.

Example 2

In Eclipse, use a ColorFieldEditor dialog to provide choices that offer a range of high contrast colors.


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Recommended development techniques

The techniques above are required; the following techniques are recommended to enhance accessibility.

  1. Avoid using reds and greens together.
  2. Use colors that meet the guidelines for effective color contrast (link resides outside of ibm.com) provided by Lighthouse International.

Required test techniques

Test the software to ensure that it complies with accessibility requirements.

Required test software

No additional software is required to test this checkpoint.

Test techniques

The following technique is required to verify this checkpoint:


Action Result

1

Visually verify the application provides at least three color combinations with sufficient contrast using Lighthouse International’s guidelines for Effective color contrast (link resides outside of ibm.com).

Pass:

Fail:

©2009, 2013 IBM Corporation

Last updated January 01, 2013.