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.
AccessibilityEvent
s are sent by the system when
something notable happens in the user interface. For example, when a
Button
is clicked, a View
is focused, etc.
AccessibilityRecord
contains information
about state change of its source 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 AccessibilityService
s.
Hence, accessibility services can facilitate additional accessibility records
to enhance feedback.
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 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.
AccessibilityManager
is a system level service that
serves as an event dispatch for 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
Activity
starts, the focus or selection of a View
changes etc. Parties interested in handling accessibility events implement and register an
accessibility service which extends AccessibilityService
.
For more information about making applications accessible, read the Accessibility developer guide.
AccessibilityEventSource | This interface is implemented by classes source of AccessibilityEvent s. |
AccessibilityManager.AccessibilityStateChangeListener | Listener for the system accessibility state. |
AccessibilityManager.TouchExplorationStateChangeListener | Listener for the system touch exploration state. |
AccessibilityEvent | This class represents accessibility events that are sent by the system when something notable happens in the user interface. |
AccessibilityManager | System level service that serves as an event dispatch for AccessibilityEvent s,
and provides facilities for querying the accessibility state of the system. |
AccessibilityNodeInfo | This class represents a node of the window content as well as actions that can be requested from its source. |
AccessibilityNodeInfo.CollectionInfo | Class with information if a node is a collection. |
AccessibilityNodeInfo.CollectionItemInfo | Class with information if a node is a collection item. |
AccessibilityNodeInfo.RangeInfo | Class with information if a node is a range. |
AccessibilityNodeProvider | This class is the contract a client should implement to enable support of a virtual view hierarchy rooted at a given view for accessibility purposes. |
AccessibilityRecord | Represents a record in an AccessibilityEvent and contains information
about state change of its source View . |
CaptioningManager | Contains methods for accessing and monitoring preferred video captioning state and visual properties. |
CaptioningManager.CaptioningChangeListener | Listener for changes in captioning properties, including enabled state and user style preferences. |
CaptioningManager.CaptionStyle | Specifies visual properties for video captions, including foreground and background colors, edge properties, and typeface. |