Added in [API level 4](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) # android.view.accessibility *** ** * ** *** 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. `https://developer.android.com/reference/android/view/accessibility/AccessibilityEvent`s are sent by the system when something notable happens in the user interface. For example, when a `https://developer.android.com/reference/android/widget/Button` is clicked, a `https://developer.android.com/reference/android/view/View` is focused, etc. `https://developer.android.com/reference/android/view/accessibility/AccessibilityRecord` contains information about state change of its source `https://developer.android.com/reference/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 `https://developer.android.com/reference/android/accessibilityservice/AccessibilityService`s. Hence, accessibility services can facilitate additional accessibility records to enhance feedback. `https://developer.android.com/reference/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 `https://developer.android.com/reference/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. `https://developer.android.com/reference/android/view/accessibility/AccessibilityManager` is a system level service that serves as an event dispatch for `https://developer.android.com/reference/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 `https://developer.android.com/reference/android/app/Activity` starts, the focus or selection of a `https://developer.android.com/reference/android/view/View` changes etc. Parties interested in handling accessibility events implement and register an accessibility service which extends `https://developer.android.com/reference/android/accessibilityservice/AccessibilityService`. ### Developer Guides For more information about making applications accessible, read the [Accessibility](https://developer.android.com/guide/topics/ui/accessibility) developer guide. ## Interfaces |---|---| | [AccessibilityEventSource](https://developer.android.com/reference/android/view/accessibility/AccessibilityEventSource) | This interface is implemented by classes source of `https://developer.android.com/reference/android/view/accessibility/AccessibilityEvent`s. | | [AccessibilityManager.AccessibilityServicesStateChangeListener](https://developer.android.com/reference/android/view/accessibility/AccessibilityManager.AccessibilityServicesStateChangeListener) | Listener for changes to the state of accessibility services. | | [AccessibilityManager.AccessibilityStateChangeListener](https://developer.android.com/reference/android/view/accessibility/AccessibilityManager.AccessibilityStateChangeListener) | Listener for the system accessibility state. | | [AccessibilityManager.AudioDescriptionRequestedChangeListener](https://developer.android.com/reference/android/view/accessibility/AccessibilityManager.AudioDescriptionRequestedChangeListener) | Listener for the audio description by default state. | | [AccessibilityManager.HighContrastTextStateChangeListener](https://developer.android.com/reference/android/view/accessibility/AccessibilityManager.HighContrastTextStateChangeListener) | Listener for the system high contrast text state. | | [AccessibilityManager.TouchExplorationStateChangeListener](https://developer.android.com/reference/android/view/accessibility/AccessibilityManager.TouchExplorationStateChangeListener) | Listener for the system touch exploration state. | ## Classes |---|---| | [AccessibilityEvent](https://developer.android.com/reference/android/view/accessibility/AccessibilityEvent) | This class represents accessibility events that are sent by the system when something notable happens in the user interface. | | [AccessibilityManager](https://developer.android.com/reference/android/view/accessibility/AccessibilityManager) | System level service that serves as an event dispatch for `https://developer.android.com/reference/android/view/accessibility/AccessibilityEvent`s, and provides facilities for querying the accessibility state of the system. | | [AccessibilityNodeInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo) | This class represents a node of the window content as well as actions that can be requested from its source. | | [AccessibilityNodeInfo.AccessibilityAction](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.AccessibilityAction) | A class defining an action that can be performed on an `https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo`. | | [AccessibilityNodeInfo.CollectionInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.CollectionInfo) | Class with information if a node is a collection. | | [AccessibilityNodeInfo.CollectionInfo.Builder](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.CollectionInfo.Builder) | The builder for CollectionInfo. | | [AccessibilityNodeInfo.CollectionItemInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.CollectionItemInfo) | Class with information if a node is a collection item. | | [AccessibilityNodeInfo.CollectionItemInfo.Builder](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.CollectionItemInfo.Builder) | Builder for creating `https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.CollectionItemInfo` objects. | | [AccessibilityNodeInfo.ExtraRenderingInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.ExtraRenderingInfo) | Class with information of a view useful to evaluate accessibility needs. | | [AccessibilityNodeInfo.ExtraRenderingInfo.Builder](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.ExtraRenderingInfo.Builder) | The builder for ExtraRenderingInfo. | | [AccessibilityNodeInfo.MathInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.MathInfo) | A class that holds information about a node that represents a mathematical expression. | | [AccessibilityNodeInfo.RangeInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.RangeInfo) | Class with information if a node is a range. | | [AccessibilityNodeInfo.Selection](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.Selection) | Represents a selection of content that may extend across more than one `https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo` instance. | | [AccessibilityNodeInfo.SelectionPosition](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.SelectionPosition) | A class which defines either the start or end of a selection that can span across multiple AccessibilityNodeInfo objects. | | [AccessibilityNodeInfo.SelectionPosition.Builder](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.SelectionPosition.Builder) | Builder for creating `https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.SelectionPosition` objects. | | [AccessibilityNodeInfo.StructuredDataInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.StructuredDataInfo) | An abstract base class for holding structured semantic information about a node. | | [AccessibilityNodeInfo.TouchDelegateInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.TouchDelegateInfo) | Class with information of touch delegated views and regions from `https://developer.android.com/reference/android/view/TouchDelegate` for the `https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo`. | | [AccessibilityNodeProvider](https://developer.android.com/reference/android/view/accessibility/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](https://developer.android.com/reference/android/view/accessibility/AccessibilityRecord) | Represents a record in an `https://developer.android.com/reference/android/view/accessibility/AccessibilityEvent` and contains information about state change of its source `https://developer.android.com/reference/android/view/View`. | | [AccessibilityRequestPreparer](https://developer.android.com/reference/android/view/accessibility/AccessibilityRequestPreparer) | Object responsible to ensuring that a `https://developer.android.com/reference/android/view/View` is prepared to meet a synchronous request for accessibility data. | | [AccessibilityWindowInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityWindowInfo) | This class represents a state snapshot of a window for accessibility purposes. | | [CaptioningManager](https://developer.android.com/reference/android/view/accessibility/CaptioningManager) | Contains methods for accessing and monitoring preferred video captioning state and visual properties. | | [CaptioningManager.CaptioningChangeListener](https://developer.android.com/reference/android/view/accessibility/CaptioningManager.CaptioningChangeListener) | Listener for changes in captioning properties, including enabled state and user style preferences. | | [CaptioningManager.CaptionStyle](https://developer.android.com/reference/android/view/accessibility/CaptioningManager.CaptionStyle) | Specifies visual properties for video captions, including foreground and background colors, edge properties, and typeface. | - ## Interfaces - [AccessibilityEventSource](https://developer.android.com/reference/android/view/accessibility/AccessibilityEventSource) - [AccessibilityManager.AccessibilityServicesStateChangeListener](https://developer.android.com/reference/android/view/accessibility/AccessibilityManager.AccessibilityServicesStateChangeListener) - [AccessibilityManager.AccessibilityStateChangeListener](https://developer.android.com/reference/android/view/accessibility/AccessibilityManager.AccessibilityStateChangeListener) - [AccessibilityManager.AudioDescriptionRequestedChangeListener](https://developer.android.com/reference/android/view/accessibility/AccessibilityManager.AudioDescriptionRequestedChangeListener) - [AccessibilityManager.HighContrastTextStateChangeListener](https://developer.android.com/reference/android/view/accessibility/AccessibilityManager.HighContrastTextStateChangeListener) - [AccessibilityManager.TouchExplorationStateChangeListener](https://developer.android.com/reference/android/view/accessibility/AccessibilityManager.TouchExplorationStateChangeListener) - ## Classes - [AccessibilityEvent](https://developer.android.com/reference/android/view/accessibility/AccessibilityEvent) - [AccessibilityManager](https://developer.android.com/reference/android/view/accessibility/AccessibilityManager) - [AccessibilityNodeInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo) - [AccessibilityNodeInfo.AccessibilityAction](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.AccessibilityAction) - [AccessibilityNodeInfo.CollectionInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.CollectionInfo) - [AccessibilityNodeInfo.CollectionInfo.Builder](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.CollectionInfo.Builder) - [AccessibilityNodeInfo.CollectionItemInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.CollectionItemInfo) - [AccessibilityNodeInfo.CollectionItemInfo.Builder](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.CollectionItemInfo.Builder) - [AccessibilityNodeInfo.ExtraRenderingInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.ExtraRenderingInfo) - [AccessibilityNodeInfo.ExtraRenderingInfo.Builder](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.ExtraRenderingInfo.Builder) - [AccessibilityNodeInfo.MathInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.MathInfo) - [AccessibilityNodeInfo.RangeInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.RangeInfo) - [AccessibilityNodeInfo.Selection](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.Selection) - [AccessibilityNodeInfo.SelectionPosition](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.SelectionPosition) - [AccessibilityNodeInfo.SelectionPosition.Builder](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.SelectionPosition.Builder) - [AccessibilityNodeInfo.StructuredDataInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.StructuredDataInfo) - [AccessibilityNodeInfo.TouchDelegateInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeInfo.TouchDelegateInfo) - [AccessibilityNodeProvider](https://developer.android.com/reference/android/view/accessibility/AccessibilityNodeProvider) - [AccessibilityRecord](https://developer.android.com/reference/android/view/accessibility/AccessibilityRecord) - [AccessibilityRequestPreparer](https://developer.android.com/reference/android/view/accessibility/AccessibilityRequestPreparer) - [AccessibilityWindowInfo](https://developer.android.com/reference/android/view/accessibility/AccessibilityWindowInfo) - [CaptioningManager](https://developer.android.com/reference/android/view/accessibility/CaptioningManager) - [CaptioningManager.CaptioningChangeListener](https://developer.android.com/reference/android/view/accessibility/CaptioningManager.CaptioningChangeListener) - [CaptioningManager.CaptionStyle](https://developer.android.com/reference/android/view/accessibility/CaptioningManager.CaptionStyle)