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Introduction
This module will focus on how text is displayed. To ensure that assistive technologies (ATs) will work correctly, applications should use operating system (OS) functions or documented application programming interfaces (APIs) to render text.
The Section 508 requirement covering this is: §1194.21 (f) Textual information shall be provided through operating system functions for displaying text. The minimum information that shall be made available is text content, text input caret location, and text attributes.
Assistive technologies interact at a low level with the operating systems they run on. This low-level access allows ATs, such as screen readers, to track textual information as it is written to the screen, so that it can be conveyed to the user in a meaningful way. Sometimes this requires the AT to modify the presentation of that information for the user. When this textual information is not written through the OS or another documented API, the assistive technology cannot access it reliably.
Most applications natively write text to the screen appropriately because they use standard controls designed for the Windows OS. However, when applications use cross-platform controls that are designed to make the application look the same on different platforms (such as Windows, Mac, or Unix), the text, input caret location and text attributes may not be exposed in Windows in a way that can be determined by AT. When applications use cross-platform controls and methods, they must expose this information in other ways, such as by using native Windows controls or by using a well-documented API. Screen readers can then pull this information out of Windows or the API. Some examples of text-based APIs are iTextServices and iSimpleTextInterface.
Remember, both testers and developers can use the checkpoints for this requirement to be sure the products they are working with will be accessible to users with disabilities, including those using assistive technology (AT).
Use the link above to look at the checkpoints now. You may wish to keep the window open as a reference to use as you complete this module.
Video Overview of this Requirement
To view an approximately one-minute video with additional information that may be helpful to testers and developers, select the video link below. The video will open in a new window; if you are using a screen reader to take this training, press Enter when you hear, "To start, press Play button."
There are four areas of particular importance for you to consider when testing software applications and operating systems for compliance with this requirement. They are the four checkpoints on the Section 508 Checklist for this requirement; each is discussed in more detail on the next page.
Select Next for that discussion.
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