Accessibility on OS X
OS X includes a wide variety of features and assistive technologies that include screen and cursor magnification, a full-featured screen reader, visual flash alerts, closed captioning support, and much more. OS X includes all the features your app needs to make it accessible to users with special needs.
Making Your App Accessible
Developers using standard controls and their subclasses will find support for assistive applications is built-in. Apple’s Accessibility APIs define how OS X apps can make their user interface available to an external assistive application or service.
Apple strongly encourages developers to support these APIs in all of their apps so they are compatible with features built into OS X such as VoiceOver, as well as other third-party products. The Xcode IDE and Cocoa frameworks make it easy to add accessibility tags like descriptions. For example, the inspector pane allows you to enter a description for any control in the user interface; that description will be synthesized into speech when VoiceOver is enabled.
How it Works
An assistive application in OS X interacts with accessibility objects in your app to allow people with disabilities to drive the user interface in non-traditional ways. For example, a VoiceOver user relies primarily on the keyboard or trackpad for control, and on Speech Synthesis and Braille for feedback. Users with low vision can set the built-in zoom, grayscale, and white-on-black display mode options in OS X to adapt the onscreen experience to their specific needs. Those who are Deaf or hard of hearing can set audible alerts to automatically flash the screen instead. And users with physical and motor disabilities will rely on AppleScript and Automator workflows to simplify complex tasks, and can take advantage of keyboard and mouse preferences to make them easier to control and use. It is important that your app work as intended for those who rely on these assistive features of OS X.
Through Accessibility APIs that support technologies such as VoiceOver, Switch Control, Zoom, Closed Captions, and Audio Descriptions, OS X provides an extraordinary opportunity to deliver a superior computing experience to every customer, including those with special needs.
Programming Guides and References