The classes in this package are used to represent screen content and changes to it as well as APIs for querying the global accessibility state of the system.

{@link android.view.accessibility.AccessibilityEvent}s are sent by the system when something notable happens in the user interface. For example, when a {@link android.widget.Button} is clicked, a {@link android.view.View} is focused, etc.

{@link android.view.accessibility.AccessibilityRecord} contains information about state change of its source {@link android.view.View}. When a view fires an accessibility event it requests from its parent to dispatch the constructed event. The parent may optionally append a record for itself for providing more context to {@link android.accessibilityservice.AccessibilityService}s. Hence, accessibility services can facilitate additional accessibility records to enhance feedback.

{@link android.view.accessibility.AccessibilityNodeInfo} represents a node of the window content as well as actions that can be requested from its source. From the point of view of an {@link android.accessibilityservice.AccessibilityService} a window content is presented as tree of accessibility node info which may or may not map one-to-one to the view hierarchy. In other words, a custom view is free to report itself as a tree of accessibility node info.

{@link android.view.accessibility.AccessibilityManager} is a system level service that serves as an event dispatch for {@link android.view.accessibility.AccessibilityEvent}s, and provides facilities for querying the accessibility state of the system. Accessibility events are generated when something notable happens in the user interface, for example an {@link android.app.Activity} starts, the focus or selection of a {@link android.view.View} changes etc. Parties interested in handling accessibility events implement and register an accessibility service which extends {@link android.accessibilityservice.AccessibilityService}.

### Developer Guides

For more information about making applications accessible, read the Accessibility developer guide.