AccessibilityDelegateCompat

Added in 1.1.0

Kotlin |Java

public class AccessibilityDelegateCompat

Known direct subclasses

ExploreByTouchHelper, RecyclerViewAccessibilityDelegate.ItemDelegate, RecyclerViewAccessibilityDelegate

`ExploreByTouchHelper`	ExploreByTouchHelper is a utility class for implementing accessibility support in custom `View`s that represent a collection of View-like logical items.
`RecyclerViewAccessibilityDelegate.ItemDelegate`	The default implementation of accessibility delegate for the individual items of the RecyclerView.
`RecyclerViewAccessibilityDelegate`	The AccessibilityDelegate used by RecyclerView.

Helper for accessing AccessibilityDelegate.

Note: On platform versions prior to API 23, delegate methods on views in the android.widget.* package are called before host methods. This prevents certain properties such as class name from being modified by overriding onInitializeAccessibilityNodeInfo, as any changes will be overwritten by the host class.

Starting in API 23, delegate methods are called after host methods, which all properties to be modified without being overwritten by the host class.

Summary

Public constructors
`AccessibilityDelegateCompat()` Creates a new instance.

Public methods
`boolean`	`dispatchPopulateAccessibilityEvent( @NonNull View host, @NonNull AccessibilityEvent event )` Dispatches an `AccessibilityEvent` to the host `View` first and then to its children for adding their text content to the event.
`@Nullable AccessibilityNodeProviderCompat`	`getAccessibilityNodeProvider(@NonNull View host)` Gets the provider for managing a virtual view hierarchy rooted at this View and reported to `AccessibilityService`s that explore the window content.
`void`	`onInitializeAccessibilityEvent( @NonNull View host, @NonNull AccessibilityEvent event )` Initializes an `AccessibilityEvent` with information about the the host View which is the event source.
`void`	`onInitializeAccessibilityNodeInfo( @NonNull View host, @NonNull AccessibilityNodeInfoCompat info )` Initializes an `AccessibilityNodeInfoCompat` with information about the host view.
`void`	`onPopulateAccessibilityEvent( @NonNull View host, @NonNull AccessibilityEvent event )` Gives a chance to the host View to populate the accessibility event with its text content.
`boolean`	`onRequestSendAccessibilityEvent( @NonNull ViewGroup host, @NonNull View child, @NonNull AccessibilityEvent event )` Called when a child of the host View has requested sending an `AccessibilityEvent` and gives an opportunity to the parent (the host) to augment the event.
`boolean`	`performAccessibilityAction( @NonNull View host, int action, @Nullable Bundle args )` Performs the specified accessibility action on the view.
`void`	`sendAccessibilityEvent(@NonNull View host, int eventType)` Sends an accessibility event of the given type.
`void`	`sendAccessibilityEventUnchecked( @NonNull View host, @NonNull AccessibilityEvent event )` Sends an accessibility event.

Public constructors

AccessibilityDelegateCompat

Added in 1.1.0

public AccessibilityDelegateCompat()

Creates a new instance.

Public methods

dispatchPopulateAccessibilityEvent

Added in 1.1.0

public boolean dispatchPopulateAccessibilityEvent(
    @NonNull View host,
    @NonNull AccessibilityEvent event
)

Dispatches an AccessibilityEvent to the host View first and then to its children for adding their text content to the event.

The default implementation behaves as View#dispatchPopulateAccessibilityEvent(AccessibilityEvent) for the case of no accessibility delegate been set.

Parameters
`@NonNull View host`	The View hosting the delegate.
`@NonNull AccessibilityEvent event`	The event.

Returns
`boolean`	True if the event population was completed.

See also
`dispatchPopulateAccessibilityEvent`	View#dispatchPopulateAccessibilityEvent(AccessibilityEvent)

getAccessibilityNodeProvider

Added in 1.1.0

public @Nullable AccessibilityNodeProviderCompat getAccessibilityNodeProvider(@NonNull View host)

Gets the provider for managing a virtual view hierarchy rooted at this View and reported to AccessibilityServices that explore the window content.

The default implementation behaves as ViewCompat#getAccessibilityNodeProvider(View) for the case of no accessibility delegate been set.

Returns
`@Nullable AccessibilityNodeProviderCompat`	The provider.

See also
`AccessibilityNodeProviderCompat`

onInitializeAccessibilityEvent

Added in 1.1.0

public void onInitializeAccessibilityEvent(
    @NonNull View host,
    @NonNull AccessibilityEvent event
)

Initializes an AccessibilityEvent with information about the the host View which is the event source.

The default implementation behaves as ViewCompat#onInitalizeAccessibilityEvent(View v, AccessibilityEvent event) for the case of no accessibility delegate been set.

Parameters
`@NonNull View host`	The View hosting the delegate.
`@NonNull AccessibilityEvent event`	The event to initialize.

See also
`onInitializeAccessibilityEvent`	ViewCompat#onInitializeAccessibilityEvent(View, AccessibilityEvent)

onInitializeAccessibilityNodeInfo

Added in 1.1.0

public void onInitializeAccessibilityNodeInfo(
    @NonNull View host,
    @NonNull AccessibilityNodeInfoCompat info
)

Initializes an AccessibilityNodeInfoCompat with information about the host view.

The default implementation behaves as ViewCompat#onInitializeAccessibilityNodeInfo(View, AccessibilityNodeInfoCompat) for the case of no accessibility delegate been set.

Parameters
`@NonNull View host`	The View hosting the delegate.
`@NonNull AccessibilityNodeInfoCompat info`	The instance to initialize.

See also
`onInitializeAccessibilityNodeInfo`	ViewCompat#onInitializeAccessibilityNodeInfo(View, AccessibilityNodeInfoCompat)

onPopulateAccessibilityEvent

Added in 1.1.0

public void onPopulateAccessibilityEvent(
    @NonNull View host,
    @NonNull AccessibilityEvent event
)

Gives a chance to the host View to populate the accessibility event with its text content.

The default implementation behaves as ViewCompat#onPopulateAccessibilityEvent(AccessibilityEvent) for the case of no accessibility delegate been set.

Parameters
`@NonNull View host`	The View hosting the delegate.
`@NonNull AccessibilityEvent event`	The accessibility event which to populate.

See also
`onPopulateAccessibilityEvent`	ViewCompat#onPopulateAccessibilityEvent(View, AccessibilityEvent)

onRequestSendAccessibilityEvent

Added in 1.1.0

public boolean onRequestSendAccessibilityEvent(
    @NonNull ViewGroup host,
    @NonNull View child,
    @NonNull AccessibilityEvent event
)

Called when a child of the host View has requested sending an AccessibilityEvent and gives an opportunity to the parent (the host) to augment the event.

The default implementation behaves as ViewGroupCompat#onRequestSendAccessibilityEvent(ViewGroup, View, AccessibilityEvent) for the case of no accessibility delegate been set.

Parameters
`@NonNull ViewGroup host`	The View hosting the delegate.
`@NonNull View child`	The child which requests sending the event.
`@NonNull AccessibilityEvent event`	The event to be sent.

Returns
`boolean`	True if the event should be sent

See also
`onRequestSendAccessibilityEvent`	ViewGroupCompat#onRequestSendAccessibilityEvent(ViewGroup, View, AccessibilityEvent)

performAccessibilityAction

Added in 1.1.0

public boolean performAccessibilityAction(
    @NonNull View host,
    int action,
    @Nullable Bundle args
)

Performs the specified accessibility action on the view. For possible accessibility actions look at AccessibilityNodeInfoCompat.

The default implementation behaves as View#performAccessibilityAction(int, Bundle) for the case of no accessibility delegate been set.

Parameters
`@NonNull View host`	View on which to perform the action.
`int action`	The action to perform.
`@Nullable Bundle args`	Optional action arguments.

Returns
`boolean`	Whether the action was performed.

See also
`performAccessibilityAction`	View#performAccessibilityAction(int, Bundle)

sendAccessibilityEvent

Added in 1.1.0

public void sendAccessibilityEvent(@NonNull View host, int eventType)

Sends an accessibility event of the given type. If accessibility is not enabled this method has no effect.

The default implementation behaves as View#sendAccessibilityEvent(int) for the case of no accessibility delegate been set.

Parameters
`@NonNull View host`	The View hosting the delegate.
`int eventType`	The type of the event to send.

See also
`sendAccessibilityEvent`	View#sendAccessibilityEvent(int)

sendAccessibilityEventUnchecked

Added in 1.1.0

public void sendAccessibilityEventUnchecked(
    @NonNull View host,
    @NonNull AccessibilityEvent event
)

Sends an accessibility event. This method behaves exactly as sendAccessibilityEvent but takes as an argument an empty AccessibilityEvent and does not perform a check whether accessibility is enabled.

The default implementation behaves as View#sendAccessibilityEventUnchecked(AccessibilityEvent) for the case of no accessibility delegate been set.

Parameters
`@NonNull View host`	The View hosting the delegate.
`@NonNull AccessibilityEvent event`	The event to send.

See also
`sendAccessibilityEventUnchecked`	View#sendAccessibilityEventUnchecked(AccessibilityEvent)