Added in [API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) Summary: [Ctors](https://developer.android.com/reference/android/accessibilityservice/AccessibilityButtonController.AccessibilityButtonCallback#pubctors) \| [Methods](https://developer.android.com/reference/android/accessibilityservice/AccessibilityButtonController.AccessibilityButtonCallback#pubmethods) \| [Inherited Methods](https://developer.android.com/reference/android/accessibilityservice/AccessibilityButtonController.AccessibilityButtonCallback#inhmethods)

# AccessibilityButtonController.AccessibilityButtonCallback

*** ** * ** ***


`
public
static

abstract
class
AccessibilityButtonController.AccessibilityButtonCallback
`


`

extends https://developer.android.com/reference/java/lang/Object


`

`


`

|---|---|
| [java.lang.Object](https://developer.android.com/reference/java/lang/Object) ||
| ↳ | android.accessibilityservice.AccessibilityButtonController.AccessibilityButtonCallback |

<br />

*** ** * ** ***

Callback for interaction with and changes to state of the accessibility button
within the system's navigation area.

## Summary

| ### Public constructors ||
|---|---|
| ` https://developer.android.com/reference/android/accessibilityservice/AccessibilityButtonController.AccessibilityButtonCallback#AccessibilityButtonCallback()() ` |

| ### Public methods ||
|---|---|
| ` void` | ` https://developer.android.com/reference/android/accessibilityservice/AccessibilityButtonController.AccessibilityButtonCallback#onAvailabilityChanged(android.accessibilityservice.AccessibilityButtonController,%20boolean)(https://developer.android.com/reference/android/accessibilityservice/AccessibilityButtonController controller, boolean available) ` Called when the availability of the accessibility button in the system's navigation area has changed. |
| ` void` | ` https://developer.android.com/reference/android/accessibilityservice/AccessibilityButtonController.AccessibilityButtonCallback#onClicked(android.accessibilityservice.AccessibilityButtonController)(https://developer.android.com/reference/android/accessibilityservice/AccessibilityButtonController controller) ` Called when the accessibility button in the system's navigation area is clicked. |

| ### Inherited methods |
|---|---|
| From class ` https://developer.android.com/reference/java/lang/Object ` |---|---| | ` https://developer.android.com/reference/java/lang/Object` | ` https://developer.android.com/reference/java/lang/Object#clone()() ` Creates and returns a copy of this object. | | ` boolean` | ` https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object)(https://developer.android.com/reference/java/lang/Object obj) ` Indicates whether some other object is "equal to" this one. | | ` void` | ` https://developer.android.com/reference/java/lang/Object#finalize()() ` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. | | ` final https://developer.android.com/reference/java/lang/Class<?>` | ` https://developer.android.com/reference/java/lang/Object#getClass()() ` Returns the runtime class of this `Object`. | | ` int` | ` https://developer.android.com/reference/java/lang/Object#hashCode()() ` Returns a hash code value for the object. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#notify()() ` Wakes up a single thread that is waiting on this object's monitor. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#notifyAll()() ` Wakes up all threads that are waiting on this object's monitor. | | ` https://developer.android.com/reference/java/lang/String` | ` https://developer.android.com/reference/java/lang/Object#toString()() ` Returns a string representation of the object. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#wait(long,%20int)(long timeoutMillis, int nanos) ` Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*, or until a certain amount of real time has elapsed. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#wait(long)(long timeoutMillis) ` Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*, or until a certain amount of real time has elapsed. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#wait()() ` Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*. | ||

## Public constructors

### AccessibilityButtonCallback

```
public AccessibilityButtonCallback ()
```

<br />

<br />

## Public methods

### onAvailabilityChanged

Added in [API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public void onAvailabilityChanged (AccessibilityButtonController controller, 
                boolean available)
```

Called when the availability of the accessibility button in the system's
navigation area has changed. The accessibility button may become unavailable
because the device shopped showing the button, the button was assigned to another
service, or for other reasons.

<br />

| Parameters ||
|---|---|
| `controller` | `AccessibilityButtonController`: the controller used to register for this callback <br /> |
| `available` | `boolean`: `true` if the accessibility button is available to this service, `false` otherwise <br /> |

### onClicked

Added in [API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public void onClicked (AccessibilityButtonController controller)
```

Called when the accessibility button in the system's navigation area is clicked.

<br />

| Parameters ||
|---|---|
| `controller` | `AccessibilityButtonController`: the controller used to register for this callback <br /> |