1<html>
2<body>
3<p>
4  The classes in this package are used to represent screen content and changes to it
5  as well as APIs for querying the global accessibility state of the system.
6</p>
7<p>
8  {@link android.view.accessibility.AccessibilityEvent}s are sent by the system when
9  something notable happens in the user interface. For example, when a
10  {@link android.widget.Button} is clicked, a {@link android.view.View} is focused, etc.
11</p>
12<p>
13  {@link android.view.accessibility.AccessibilityRecord} contains information
14  about state change of its source {@link android.view.View}. When a view fires
15  an accessibility event it requests from its parent to dispatch the
16  constructed event. The parent may optionally append a record for itself for
17  providing more context to {@link android.accessibilityservice.AccessibilityService}s.
18  Hence, accessibility services can facilitate additional accessibility records
19  to enhance feedback.
20</p>
21<p>
22  {@link android.view.accessibility.AccessibilityNodeInfo} represents a node of the
23  window content as well as actions that can be requested from its source. From the point
24  of view of an {@link android.accessibilityservice.AccessibilityService} a window content is
25  presented as tree of accessibility node info which may or may not map one-to-one
26  to the view hierarchy. In other words, a custom view is free to report itself as
27  a tree of accessibility node info.
28</p>
29<p>
30  {@link android.view.accessibility.AccessibilityManager} is a system level service that
31  serves as an event dispatch for  {@link android.view.accessibility.AccessibilityEvent}s,
32  and provides facilities for querying the accessibility state of the system. Accessibility
33  events are generated when something notable happens in the user interface, for example an
34  {@link android.app.Activity} starts, the focus or selection of a {@link android.view.View}
35  changes etc. Parties interested in handling accessibility events implement and register an
36  accessibility service which extends {@link android.accessibilityservice.AccessibilityService}.
37</p>
38<div class="special reference">
39<h3>Developer Guides</h3>
40<p>For more information about making applications accessible, read the
41<a href="{@docRoot}guide/topics/ui/accessibility/index.html">Accessibility</a>
42developer guide.</p>
43</div>
44
45</body>
46</html>
47