AccessibilityService
public
abstract
class
AccessibilityService
extends Service
java.lang.Object | ||||
↳ | android.content.Context | |||
↳ | android.content.ContextWrapper | |||
↳ | android.app.Service | |||
↳ | android.accessibilityservice.AccessibilityService |
Accessibility services should only be used to assist users with disabilities in using
Android devices and apps. They run in the background and receive callbacks by the system
when AccessibilityEvent
s are fired. Such events denote some state transition
in the user interface, for example, the focus has changed, a button has been clicked,
etc. Such a service can optionally request the capability for querying the content
of the active window. Development of an accessibility service requires extending this
class and implementing its abstract methods.
Developer Guides
For more information about creating AccessibilityServices, read the Accessibility developer guide.
Lifecycle
The lifecycle of an accessibility service is managed exclusively by the system and
follows the established service life cycle. Starting an accessibility service is triggered
exclusively by the user explicitly turning the service on in device settings. After the system
binds to a service, it calls AccessibilityService.onServiceConnected()
. This method can
be overridden by clients that want to perform post binding setup.
An accessibility service stops either when the user turns it off in device settings or when
it calls AccessibilityService.disableSelf()
.
Declaration
An accessibility is declared as any other service in an AndroidManifest.xml, but it must do two things:
-
Specify that it handles the "android.accessibilityservice.AccessibilityService"
Intent
. -
Request the
Manifest.permission.BIND_ACCESSIBILITY_SERVICE
permission to ensure that only the system can bind to it.
<service android:name=".MyAccessibilityService" android:permission="android.permission.BIND_ACCESSIBILITY_SERVICE"> <intent-filter> <action android:name="android.accessibilityservice.AccessibilityService" /> </intent-filter> . . . </service>
Configuration
An accessibility service can be configured to receive specific types of accessibility events, listen only to specific packages, get events from each type only once in a given time frame, retrieve window content, specify a settings activity, etc.
There are two approaches for configuring an accessibility service:
-
Providing a
meta-data
entry in the manifest when declaring the service. A service declaration with a meta-data tag is presented below:<service android:name=".MyAccessibilityService"> <intent-filter> <action android:name="android.accessibilityservice.AccessibilityService" /> </intent-filter> <meta-data android:name="android.accessibilityservice" android:resource="@xml/accessibilityservice" /> </service>
Note: This approach enables setting all properties.
For more details refer to
SERVICE_META_DATA
and<
.accessibility-service
> -
Calling
AccessibilityService.setServiceInfo(AccessibilityServiceInfo)
. Note that this method can be called any time to dynamically change the service configuration.Note: This approach enables setting only dynamically configurable properties:
AccessibilityServiceInfo.eventTypes
,AccessibilityServiceInfo.feedbackType
,AccessibilityServiceInfo.flags
,AccessibilityServiceInfo.notificationTimeout
,AccessibilityServiceInfo.packageNames
For more details refer to
AccessibilityServiceInfo
.
Retrieving window content
A service can specify in its declaration that it can retrieve window
content which is represented as a tree of AccessibilityWindowInfo
and
AccessibilityNodeInfo
objects. Note that
declaring this capability requires that the service declares its configuration via
an XML resource referenced by SERVICE_META_DATA
.
Window content may be retrieved with
AccessibilityEvent.getSource()
,
AccessibilityService.findFocus(int)
,
AccessibilityService.getWindows()
, or
AccessibilityService.getRootInActiveWindow()
.
Note An accessibility service may have requested to be notified for a subset of the event types, and thus be unaware when the node hierarchy has changed. It is also possible for a node to contain outdated information because the window content may change at any time.
Drawing Accessibility Overlays
Accessibility services can draw overlays on top of existing screen contents. Accessibility overlays can be used to visually highlight items on the screen e.g. indicate the current item with accessibility focus. Overlays can also offer the user a way to interact with the service directly and quickly customize the service's behavior.
Accessibility overlays can be attached to a particular window or to the display itself.
Attaching an overlay to a window allows the overly to move, grow and shrink as the window does.
The overlay will maintain the same relative position within the window bounds as the window
moves. The overlay will also maintain the same relative position within the window bounds if
the window is resized.
To attach an overlay to a window, use attachAccessibilityOverlayToWindow(int, SurfaceControl)
.
Attaching an overlay to the display means that the overlay is independent of the active
windows on that display.
To attach an overlay to a display, use attachAccessibilityOverlayToDisplay(int, SurfaceControl)
.
When positioning an overlay that is attached to a window, the service must use window
coordinates. In order to position an overlay on top of an existing UI element it is necessary
to know the bounds of that element in window coordinates. To find the bounds in window
coordinates of an element, find the corresponding AccessibilityNodeInfo
as discussed
above and call AccessibilityNodeInfo.getBoundsInWindow
.
Notification strategy
All accessibility services are notified of all events they have requested, regardless of their feedback type.
Note: The event notification timeout is useful to avoid propagating events to the client too frequently since this is accomplished via an expensive interprocess call. One can think of the timeout as a criteria to determine when event generation has settled down.
Event types
AccessibilityEvent.TYPE_VIEW_CLICKED
AccessibilityEvent.TYPE_VIEW_LONG_CLICKED
AccessibilityEvent.TYPE_VIEW_FOCUSED
AccessibilityEvent.TYPE_VIEW_SELECTED
AccessibilityEvent.TYPE_VIEW_TEXT_CHANGED
AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED
AccessibilityEvent.TYPE_NOTIFICATION_STATE_CHANGED
AccessibilityEvent.TYPE_TOUCH_EXPLORATION_GESTURE_START
AccessibilityEvent.TYPE_TOUCH_EXPLORATION_GESTURE_END
AccessibilityEvent.TYPE_VIEW_HOVER_ENTER
AccessibilityEvent.TYPE_VIEW_HOVER_EXIT
AccessibilityEvent.TYPE_VIEW_SCROLLED
AccessibilityEvent.TYPE_VIEW_TEXT_SELECTION_CHANGED
AccessibilityEvent.TYPE_WINDOW_CONTENT_CHANGED
AccessibilityEvent.TYPE_ANNOUNCEMENT
AccessibilityEvent.TYPE_GESTURE_DETECTION_START
AccessibilityEvent.TYPE_GESTURE_DETECTION_END
AccessibilityEvent.TYPE_TOUCH_INTERACTION_START
AccessibilityEvent.TYPE_TOUCH_INTERACTION_END
AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUSED
AccessibilityEvent.TYPE_WINDOWS_CHANGED
AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUS_CLEARED
Feedback types
AccessibilityServiceInfo.FEEDBACK_AUDIBLE
AccessibilityServiceInfo.FEEDBACK_HAPTIC
AccessibilityServiceInfo.FEEDBACK_SPOKEN
AccessibilityServiceInfo.FEEDBACK_VISUAL
AccessibilityServiceInfo.FEEDBACK_GENERIC
AccessibilityServiceInfo.FEEDBACK_BRAILLE
Summary
Nested classes | |
---|---|
class |
AccessibilityService.GestureResultCallback
Class used to report status of dispatched gestures |
class |
AccessibilityService.MagnificationController
Used to control and query the state of display magnification. |
class |
AccessibilityService.ScreenshotResult
Can be used to construct a bitmap of the screenshot or any other operations for
|
class |
AccessibilityService.SoftKeyboardController
Used to control, query, and listen for changes to the soft keyboard show mode. |
interface |
AccessibilityService.TakeScreenshotCallback
Interface used to report status of taking screenshot. |
Constants | |
---|---|
int |
ERROR_TAKE_SCREENSHOT_INTERNAL_ERROR
The status of taking screenshot is failure and the reason is internal error. |
int |
ERROR_TAKE_SCREENSHOT_INTERVAL_TIME_SHORT
The status of taking screenshot is failure and the reason is that too little time has elapsed since the last screenshot. |
int |
ERROR_TAKE_SCREENSHOT_INVALID_DISPLAY
The status of taking screenshot is failure and the reason is invalid display Id. |
int |
ERROR_TAKE_SCREENSHOT_INVALID_WINDOW
The status of taking screenshot is failure and the reason is invalid accessibility window Id. |
int |
ERROR_TAKE_SCREENSHOT_NO_ACCESSIBILITY_ACCESS
The status of taking screenshot is failure and the reason is no accessibility access. |
int |
ERROR_TAKE_SCREENSHOT_SECURE_WINDOW
The status of taking screenshot is failure and the reason is the window contains secure content. |
int |
GESTURE_2_FINGER_DOUBLE_TAP
The user has performed a two-finger double tap gesture on the touch screen. |
int |
GESTURE_2_FINGER_DOUBLE_TAP_AND_HOLD
The user has performed a two-finger double tap and hold gesture on the touch screen. |
int |
GESTURE_2_FINGER_SINGLE_TAP
The user has performed a two-finger single tap gesture on the touch screen. |
int |
GESTURE_2_FINGER_SWIPE_DOWN
The user has performed a two-finger swipe down gesture on the touch screen. |
int |
GESTURE_2_FINGER_SWIPE_LEFT
The user has performed a two-finger swipe left gesture on the touch screen. |
int |
GESTURE_2_FINGER_SWIPE_RIGHT
The user has performed a two-finger swipe right gesture on the touch screen. |
int |
GESTURE_2_FINGER_SWIPE_UP
The user has performed a two-finger swipe up gesture on the touch screen. |
int |
GESTURE_2_FINGER_TRIPLE_TAP
The user has performed a two-finger triple tap gesture on the touch screen. |
int |
GESTURE_2_FINGER_TRIPLE_TAP_AND_HOLD
The user has performed a two-finger triple-tap and hold gesture on the touch screen. |
int |
GESTURE_3_FINGER_DOUBLE_TAP
The user has performed a three-finger double tap gesture on the touch screen. |
int |
GESTURE_3_FINGER_DOUBLE_TAP_AND_HOLD
The user has performed a three-finger double tap and hold gesture on the touch screen. |
int |
GESTURE_3_FINGER_SINGLE_TAP
The user has performed a three-finger single tap gesture on the touch screen. |
int |
GESTURE_3_FINGER_SINGLE_TAP_AND_HOLD
The user has performed a three-finger single-tap and hold gesture on the touch screen. |
int |
GESTURE_3_FINGER_SWIPE_DOWN
The user has performed a three-finger swipe down gesture on the touch screen. |
int |
GESTURE_3_FINGER_SWIPE_LEFT
The user has performed a three-finger swipe left gesture on the touch screen. |
int |
GESTURE_3_FINGER_SWIPE_RIGHT
The user has performed a three-finger swipe right gesture on the touch screen. |
int |
GESTURE_3_FINGER_SWIPE_UP
The user has performed a three-finger swipe up gesture on the touch screen. |
int |
GESTURE_3_FINGER_TRIPLE_TAP
The user has performed a three-finger triple tap gesture on the touch screen. |
int |
GESTURE_3_FINGER_TRIPLE_TAP_AND_HOLD
The user has performed a three-finger triple-tap and hold gesture on the touch screen. |
int |
GESTURE_4_FINGER_DOUBLE_TAP
The user has performed a four-finger double tap gesture on the touch screen. |
int |
GESTURE_4_FINGER_DOUBLE_TAP_AND_HOLD
The user has performed a two-finger double tap and hold gesture on the touch screen. |
int |
GESTURE_4_FINGER_SINGLE_TAP
The user has performed a four-finger single tap gesture on the touch screen. |
int |
GESTURE_4_FINGER_SWIPE_DOWN
The user has performed a four-finger swipe down gesture on the touch screen. |
int |
GESTURE_4_FINGER_SWIPE_LEFT
The user has performed a four-finger swipe left gesture on the touch screen. |
int |
GESTURE_4_FINGER_SWIPE_RIGHT
The user has performed a four-finger swipe right gesture on the touch screen. |
int |
GESTURE_4_FINGER_SWIPE_UP
The user has performed a four-finger swipe up gesture on the touch screen. |
int |
GESTURE_4_FINGER_TRIPLE_TAP
The user has performed a four-finger triple tap gesture on the touch screen. |
int |
GESTURE_DOUBLE_TAP
The user has performed a double tap gesture on the touch screen. |
int |
GESTURE_DOUBLE_TAP_AND_HOLD
The user has performed a double tap and hold gesture on the touch screen. |
int |
GESTURE_SWIPE_DOWN
The user has performed a swipe down gesture on the touch screen. |
int |
GESTURE_SWIPE_DOWN_AND_LEFT
The user has performed a down and left gesture on the touch screen. |
int |
GESTURE_SWIPE_DOWN_AND_RIGHT
The user has performed a down and right gesture on the touch screen. |
int |
GESTURE_SWIPE_DOWN_AND_UP
The user has performed a swipe down and up gesture on the touch screen. |
int |
GESTURE_SWIPE_LEFT
The user has performed a swipe left gesture on the touch screen. |
int |
GESTURE_SWIPE_LEFT_AND_DOWN
The user has performed a left and down gesture on the touch screen. |
int |
GESTURE_SWIPE_LEFT_AND_RIGHT
The user has performed a swipe left and right gesture on the touch screen. |
int |
GESTURE_SWIPE_LEFT_AND_UP
The user has performed a left and up gesture on the touch screen. |
int |
GESTURE_SWIPE_RIGHT
The user has performed a swipe right gesture on the touch screen. |
int |
GESTURE_SWIPE_RIGHT_AND_DOWN
The user has performed a right and down gesture on the touch screen. |
int |
GESTURE_SWIPE_RIGHT_AND_LEFT
The user has performed a swipe right and left gesture on the touch screen. |
int |
GESTURE_SWIPE_RIGHT_AND_UP
The user has performed a right and up gesture on the touch screen. |
int |
GESTURE_SWIPE_UP
The user has performed a swipe up gesture on the touch screen. |
int |
GESTURE_SWIPE_UP_AND_DOWN
The user has performed a swipe up and down gesture on the touch screen. |
int |
GESTURE_SWIPE_UP_AND_LEFT
The user has performed an up and left gesture on the touch screen. |
int |
GESTURE_SWIPE_UP_AND_RIGHT
The user has performed an up and right gesture on the touch screen. |
int |
GESTURE_UNKNOWN
The user has performed an unrecognized gesture on the touch screen. |
int |
GLOBAL_ACTION_ACCESSIBILITY_ALL_APPS
Action to show Launcher's all apps. |
int |
GLOBAL_ACTION_ACCESSIBILITY_BUTTON
Action to trigger the Accessibility Button |
int |
GLOBAL_ACTION_ACCESSIBILITY_BUTTON_CHOOSER
Action to bring up the Accessibility Button's chooser menu |
int |
GLOBAL_ACTION_ACCESSIBILITY_SHORTCUT
Action to trigger the Accessibility Shortcut. |
int |
GLOBAL_ACTION_BACK
Action to go back. |
int |
GLOBAL_ACTION_DISMISS_NOTIFICATION_SHADE
Action to dismiss the notification shade |
int |
GLOBAL_ACTION_DPAD_CENTER
Action to trigger dpad center keyevent. |
int |
GLOBAL_ACTION_DPAD_DOWN
Action to trigger dpad down keyevent. |
int |
GLOBAL_ACTION_DPAD_LEFT
Action to trigger dpad left keyevent. |
int |
GLOBAL_ACTION_DPAD_RIGHT
Action to trigger dpad right keyevent. |
int |
GLOBAL_ACTION_DPAD_UP
Action to trigger dpad up keyevent. |
int |
GLOBAL_ACTION_HOME
Action to go home. |
int |
GLOBAL_ACTION_KEYCODE_HEADSETHOOK
Action to send the KEYCODE_HEADSETHOOK KeyEvent, which is used to answer and hang up calls and play and stop media. |
int |
GLOBAL_ACTION_LOCK_SCREEN
Action to lock the screen |
int |
GLOBAL_ACTION_MEDIA_PLAY_PAUSE
Action to trigger media play/pause key event. |
int |
GLOBAL_ACTION_MENU
Action to trigger menu key event. |
int |
GLOBAL_ACTION_NOTIFICATIONS
Action to open the notifications. |
int |
GLOBAL_ACTION_POWER_DIALOG
Action to open the power long-press dialog. |
int |
GLOBAL_ACTION_QUICK_SETTINGS
Action to open the quick settings. |
int |
GLOBAL_ACTION_RECENTS
Action to toggle showing the overview of recent apps. |
int |
GLOBAL_ACTION_TAKE_SCREENSHOT
Action to take a screenshot |
int |
GLOBAL_ACTION_TOGGLE_SPLIT_SCREEN
Action to toggle docking the current app's window. |
int |
OVERLAY_RESULT_INTERNAL_ERROR
Result code indicating the overlay could not be attached due to an internal error and not because of problems with the input. |
int |
OVERLAY_RESULT_INVALID
Result code indicating the overlay could not be attached because the specified display or window id was invalid. |
int |
OVERLAY_RESULT_SUCCESS
Result code indicating the overlay was successfully attached. |
String |
SERVICE_INTERFACE
The |
String |
SERVICE_META_DATA
Name under which an AccessibilityService component publishes information about itself. |
int |
SHOW_MODE_AUTO
Allow the system to control when the soft keyboard is shown. |
int |
SHOW_MODE_HIDDEN
Never show the soft keyboard. |
int |
SHOW_MODE_IGNORE_HARD_KEYBOARD
Allow the soft keyboard to be shown, even if a hard keyboard is connected |
Inherited constants |
---|
Public constructors | |
---|---|
AccessibilityService()
|
Public methods | |
---|---|
void
|
attachAccessibilityOverlayToDisplay(int displayId, SurfaceControl sc)
Attaches a |
final
void
|
attachAccessibilityOverlayToDisplay(int displayId, SurfaceControl sc, Executor executor, IntConsumer callback)
Attaches a |
final
void
|
attachAccessibilityOverlayToWindow(int accessibilityWindowId, SurfaceControl sc, Executor executor, IntConsumer callback)
Attaches an accessibility overlay |
void
|
attachAccessibilityOverlayToWindow(int accessibilityWindowId, SurfaceControl sc)
Attaches an accessibility overlay |
boolean
|
clearCache()
Clears the cache. |
boolean
|
clearCachedSubtree(AccessibilityNodeInfo node)
Invalidates |
Context
|
createDisplayContext(Display display)
Returns a new |
Context
|
createWindowContext(int type, Bundle options)
Creates a Context for a non-activity window. |
Context
|
createWindowContext(Display display, int type, Bundle options)
Creates a |
final
void
|
disableSelf()
Disables the service. |
final
boolean
|
dispatchGesture(GestureDescription gesture, AccessibilityService.GestureResultCallback callback, Handler handler)
Dispatch a gesture to the touch screen. |
AccessibilityNodeInfo
|
findFocus(int focus)
Find the view that has the specified focus type. |
final
AccessibilityButtonController
|
getAccessibilityButtonController(int displayId)
Returns the controller of specified logical display for the accessibility button within the system's navigation area. |
final
AccessibilityButtonController
|
getAccessibilityButtonController()
Returns the controller for the accessibility button within the system's navigation area. |
final
BrailleDisplayController
|
getBrailleDisplayController()
Returns the |
final
FingerprintGestureController
|
getFingerprintGestureController()
Get the controller for fingerprint gestures. |
final
InputMethod
|
getInputMethod()
Returns the InputMethod instance after the system calls |
final
AccessibilityService.MagnificationController
|
getMagnificationController()
Returns the magnification controller, which may be used to query and modify the state of display magnification. |
AccessibilityNodeInfo
|
getRootInActiveWindow()
Gets the root node in the currently active window if this service can retrieve window content. |
AccessibilityNodeInfo
|
getRootInActiveWindow(int prefetchingStrategy)
Gets the root node in the currently active window if this service can retrieve window content. |
final
AccessibilityServiceInfo
|
getServiceInfo()
Gets the an |
final
AccessibilityService.SoftKeyboardController
|
getSoftKeyboardController()
Returns the soft keyboard controller, which may be used to query and modify the soft keyboard show mode. |
final
List<AccessibilityNodeInfo.AccessibilityAction>
|
getSystemActions()
Returns a list of system actions available in the system right now. |
Object
|
getSystemService(String name)
Return the handle to a system-level service by name. |
final
TouchInteractionController
|
getTouchInteractionController(int displayId)
Returns the touch interaction controller for the specified logical display, which may be used to detect gestures and otherwise control touch interactions. |
List<AccessibilityWindowInfo>
|
getWindows()
Gets the windows on the screen of the default display. |
final
SparseArray<List<AccessibilityWindowInfo>>
|
getWindowsOnAllDisplays()
Gets the windows on the screen of all displays. |
boolean
|
isCacheEnabled()
Returns |
boolean
|
isNodeInCache(AccessibilityNodeInfo node)
Checks if |
abstract
void
|
onAccessibilityEvent(AccessibilityEvent event)
Callback for |
final
IBinder
|
onBind(Intent intent)
Implement to return the implementation of the internal accessibility service interface. |
InputMethod
|
onCreateInputMethod()
The default implementation returns our default |
boolean
|
onGesture(AccessibilityGestureEvent gestureEvent)
Called by the system when the user performs a specific gesture on the specific touch screen. |
abstract
void
|
onInterrupt()
Callback for interrupting the accessibility feedback. |
void
|
onMotionEvent(MotionEvent event)
Callback that allows an accessibility service to observe generic |
void
|
onSystemActionsChanged()
This is called when the system action list is changed. |
final
boolean
|
performGlobalAction(int action)
Performs a global action. |
void
|
setAccessibilityFocusAppearance(int strokeWidth, int color)
Sets the strokeWidth and color of the accessibility focus rectangle. |
void
|
setAnimationScale(float scale)
Sets the system settings values that control the scaling factor for animations. |
boolean
|
setCacheEnabled(boolean enabled)
Sets the cache status. |
void
|
setGestureDetectionPassthroughRegion(int displayId, Region region)
When |
final
void
|
setServiceInfo(AccessibilityServiceInfo info)
Sets the |
void
|
setTouchExplorationPassthroughRegion(int displayId, Region region)
When |
void
|
takeScreenshot(int displayId, Executor executor, AccessibilityService.TakeScreenshotCallback callback)
Takes a screenshot of the specified display and returns it via an
|
void
|
takeScreenshotOfWindow(int accessibilityWindowId, Executor executor, AccessibilityService.TakeScreenshotCallback callback)
Takes a screenshot of the specified window and returns it via an
|
Protected methods | |
---|---|
boolean
|
onGesture(int gestureId)
This method was deprecated
in API level 30.
Override |
boolean
|
onKeyEvent(KeyEvent event)
Callback that allows an accessibility service to observe the key events before they are passed to the rest of the system. |
void
|
onServiceConnected()
This method is a part of the |
Inherited methods | |
---|---|
Constants
ERROR_TAKE_SCREENSHOT_INTERNAL_ERROR
public static final int ERROR_TAKE_SCREENSHOT_INTERNAL_ERROR
The status of taking screenshot is failure and the reason is internal error.
Constant Value: 1 (0x00000001)
ERROR_TAKE_SCREENSHOT_INTERVAL_TIME_SHORT
public static final int ERROR_TAKE_SCREENSHOT_INTERVAL_TIME_SHORT
The status of taking screenshot is failure and the reason is that too little time has elapsed since the last screenshot.
Constant Value: 3 (0x00000003)
ERROR_TAKE_SCREENSHOT_INVALID_DISPLAY
public static final int ERROR_TAKE_SCREENSHOT_INVALID_DISPLAY
The status of taking screenshot is failure and the reason is invalid display Id.
Constant Value: 4 (0x00000004)
ERROR_TAKE_SCREENSHOT_INVALID_WINDOW
public static final int ERROR_TAKE_SCREENSHOT_INVALID_WINDOW
The status of taking screenshot is failure and the reason is invalid accessibility window Id.
Constant Value: 5 (0x00000005)
ERROR_TAKE_SCREENSHOT_NO_ACCESSIBILITY_ACCESS
public static final int ERROR_TAKE_SCREENSHOT_NO_ACCESSIBILITY_ACCESS
The status of taking screenshot is failure and the reason is no accessibility access.
Constant Value: 2 (0x00000002)
ERROR_TAKE_SCREENSHOT_SECURE_WINDOW
public static final int ERROR_TAKE_SCREENSHOT_SECURE_WINDOW
The status of taking screenshot is failure and the reason is the window contains secure content.
See also:
Constant Value: 6 (0x00000006)
GESTURE_2_FINGER_DOUBLE_TAP
public static final int GESTURE_2_FINGER_DOUBLE_TAP
The user has performed a two-finger double tap gesture on the touch screen.
Constant Value: 20 (0x00000014)
GESTURE_2_FINGER_DOUBLE_TAP_AND_HOLD
public static final int GESTURE_2_FINGER_DOUBLE_TAP_AND_HOLD
The user has performed a two-finger double tap and hold gesture on the touch screen.
Constant Value: 40 (0x00000028)
GESTURE_2_FINGER_SINGLE_TAP
public static final int GESTURE_2_FINGER_SINGLE_TAP
The user has performed a two-finger single tap gesture on the touch screen.
Constant Value: 19 (0x00000013)
GESTURE_2_FINGER_SWIPE_DOWN
public static final int GESTURE_2_FINGER_SWIPE_DOWN
The user has performed a two-finger swipe down gesture on the touch screen.
Constant Value: 26 (0x0000001a)
GESTURE_2_FINGER_SWIPE_LEFT
public static final int GESTURE_2_FINGER_SWIPE_LEFT
The user has performed a two-finger swipe left gesture on the touch screen.
Constant Value: 27 (0x0000001b)
GESTURE_2_FINGER_SWIPE_RIGHT
public static final int GESTURE_2_FINGER_SWIPE_RIGHT
The user has performed a two-finger swipe right gesture on the touch screen.
Constant Value: 28 (0x0000001c)
GESTURE_2_FINGER_SWIPE_UP
public static final int GESTURE_2_FINGER_SWIPE_UP
The user has performed a two-finger swipe up gesture on the touch screen.
Constant Value: 25 (0x00000019)
GESTURE_2_FINGER_TRIPLE_TAP
public static final int GESTURE_2_FINGER_TRIPLE_TAP
The user has performed a two-finger triple tap gesture on the touch screen.
Constant Value: 21 (0x00000015)
GESTURE_2_FINGER_TRIPLE_TAP_AND_HOLD
public static final int GESTURE_2_FINGER_TRIPLE_TAP_AND_HOLD
The user has performed a two-finger triple-tap and hold gesture on the touch screen.
Constant Value: 43 (0x0000002b)
GESTURE_3_FINGER_DOUBLE_TAP
public static final int GESTURE_3_FINGER_DOUBLE_TAP
The user has performed a three-finger double tap gesture on the touch screen.
Constant Value: 23 (0x00000017)
GESTURE_3_FINGER_DOUBLE_TAP_AND_HOLD
public static final int GESTURE_3_FINGER_DOUBLE_TAP_AND_HOLD
The user has performed a three-finger double tap and hold gesture on the touch screen.
Constant Value: 41 (0x00000029)
GESTURE_3_FINGER_SINGLE_TAP
public static final int GESTURE_3_FINGER_SINGLE_TAP
The user has performed a three-finger single tap gesture on the touch screen.
Constant Value: 22 (0x00000016)
GESTURE_3_FINGER_SINGLE_TAP_AND_HOLD
public static final int GESTURE_3_FINGER_SINGLE_TAP_AND_HOLD
The user has performed a three-finger single-tap and hold gesture on the touch screen.
Constant Value: 44 (0x0000002c)
GESTURE_3_FINGER_SWIPE_DOWN
public static final int GESTURE_3_FINGER_SWIPE_DOWN
The user has performed a three-finger swipe down gesture on the touch screen.
Constant Value: 30 (0x0000001e)
GESTURE_3_FINGER_SWIPE_LEFT
public static final int GESTURE_3_FINGER_SWIPE_LEFT
The user has performed a three-finger swipe left gesture on the touch screen.
Constant Value: 31 (0x0000001f)
GESTURE_3_FINGER_SWIPE_RIGHT
public static final int GESTURE_3_FINGER_SWIPE_RIGHT
The user has performed a three-finger swipe right gesture on the touch screen.
Constant Value: 32 (0x00000020)
GESTURE_3_FINGER_SWIPE_UP
public static final int GESTURE_3_FINGER_SWIPE_UP
The user has performed a three-finger swipe up gesture on the touch screen.
Constant Value: 29 (0x0000001d)
GESTURE_3_FINGER_TRIPLE_TAP
public static final int GESTURE_3_FINGER_TRIPLE_TAP
The user has performed a three-finger triple tap gesture on the touch screen.
Constant Value: 24 (0x00000018)
GESTURE_3_FINGER_TRIPLE_TAP_AND_HOLD
public static final int GESTURE_3_FINGER_TRIPLE_TAP_AND_HOLD
The user has performed a three-finger triple-tap and hold gesture on the touch screen.
Constant Value: 45 (0x0000002d)
GESTURE_4_FINGER_DOUBLE_TAP
public static final int GESTURE_4_FINGER_DOUBLE_TAP
The user has performed a four-finger double tap gesture on the touch screen.
Constant Value: 38 (0x00000026)
GESTURE_4_FINGER_DOUBLE_TAP_AND_HOLD
public static final int GESTURE_4_FINGER_DOUBLE_TAP_AND_HOLD
The user has performed a two-finger double tap and hold gesture on the touch screen.
Constant Value: 42 (0x0000002a)
GESTURE_4_FINGER_SINGLE_TAP
public static final int GESTURE_4_FINGER_SINGLE_TAP
The user has performed a four-finger single tap gesture on the touch screen.
Constant Value: 37 (0x00000025)
GESTURE_4_FINGER_SWIPE_DOWN
public static final int GESTURE_4_FINGER_SWIPE_DOWN
The user has performed a four-finger swipe down gesture on the touch screen.
Constant Value: 34 (0x00000022)
GESTURE_4_FINGER_SWIPE_LEFT
public static final int GESTURE_4_FINGER_SWIPE_LEFT
The user has performed a four-finger swipe left gesture on the touch screen.
Constant Value: 35 (0x00000023)
GESTURE_4_FINGER_SWIPE_RIGHT
public static final int GESTURE_4_FINGER_SWIPE_RIGHT
The user has performed a four-finger swipe right gesture on the touch screen.
Constant Value: 36 (0x00000024)
GESTURE_4_FINGER_SWIPE_UP
public static final int GESTURE_4_FINGER_SWIPE_UP
The user has performed a four-finger swipe up gesture on the touch screen.
Constant Value: 33 (0x00000021)
GESTURE_4_FINGER_TRIPLE_TAP
public static final int GESTURE_4_FINGER_TRIPLE_TAP
The user has performed a four-finger triple tap gesture on the touch screen.
Constant Value: 39 (0x00000027)
GESTURE_DOUBLE_TAP
public static final int GESTURE_DOUBLE_TAP
The user has performed a double tap gesture on the touch screen.
Constant Value: 17 (0x00000011)
GESTURE_DOUBLE_TAP_AND_HOLD
public static final int GESTURE_DOUBLE_TAP_AND_HOLD
The user has performed a double tap and hold gesture on the touch screen.
Constant Value: 18 (0x00000012)
GESTURE_SWIPE_DOWN
public static final int GESTURE_SWIPE_DOWN
The user has performed a swipe down gesture on the touch screen.
Constant Value: 2 (0x00000002)
GESTURE_SWIPE_DOWN_AND_LEFT
public static final int GESTURE_SWIPE_DOWN_AND_LEFT
The user has performed a down and left gesture on the touch screen.
Constant Value: 15 (0x0000000f)
GESTURE_SWIPE_DOWN_AND_RIGHT
public static final int GESTURE_SWIPE_DOWN_AND_RIGHT
The user has performed a down and right gesture on the touch screen.
Constant Value: 16 (0x00000010)
GESTURE_SWIPE_DOWN_AND_UP
public static final int GESTURE_SWIPE_DOWN_AND_UP
The user has performed a swipe down and up gesture on the touch screen.
Constant Value: 8 (0x00000008)
GESTURE_SWIPE_LEFT
public static final int GESTURE_SWIPE_LEFT
The user has performed a swipe left gesture on the touch screen.
Constant Value: 3 (0x00000003)
GESTURE_SWIPE_LEFT_AND_DOWN
public static final int GESTURE_SWIPE_LEFT_AND_DOWN
The user has performed a left and down gesture on the touch screen.
Constant Value: 10 (0x0000000a)
GESTURE_SWIPE_LEFT_AND_RIGHT
public static final int GESTURE_SWIPE_LEFT_AND_RIGHT
The user has performed a swipe left and right gesture on the touch screen.
Constant Value: 5 (0x00000005)
GESTURE_SWIPE_LEFT_AND_UP
public static final int GESTURE_SWIPE_LEFT_AND_UP
The user has performed a left and up gesture on the touch screen.
Constant Value: 9 (0x00000009)
GESTURE_SWIPE_RIGHT
public static final int GESTURE_SWIPE_RIGHT
The user has performed a swipe right gesture on the touch screen.
Constant Value: 4 (0x00000004)
GESTURE_SWIPE_RIGHT_AND_DOWN
public static final int GESTURE_SWIPE_RIGHT_AND_DOWN
The user has performed a right and down gesture on the touch screen.
Constant Value: 12 (0x0000000c)
GESTURE_SWIPE_RIGHT_AND_LEFT
public static final int GESTURE_SWIPE_RIGHT_AND_LEFT
The user has performed a swipe right and left gesture on the touch screen.
Constant Value: 6 (0x00000006)
GESTURE_SWIPE_RIGHT_AND_UP
public static final int GESTURE_SWIPE_RIGHT_AND_UP
The user has performed a right and up gesture on the touch screen.
Constant Value: 11 (0x0000000b)
GESTURE_SWIPE_UP
public static final int GESTURE_SWIPE_UP
The user has performed a swipe up gesture on the touch screen.
Constant Value: 1 (0x00000001)
GESTURE_SWIPE_UP_AND_DOWN
public static final int GESTURE_SWIPE_UP_AND_DOWN
The user has performed a swipe up and down gesture on the touch screen.
Constant Value: 7 (0x00000007)
GESTURE_SWIPE_UP_AND_LEFT
public static final int GESTURE_SWIPE_UP_AND_LEFT
The user has performed an up and left gesture on the touch screen.
Constant Value: 13 (0x0000000d)
GESTURE_SWIPE_UP_AND_RIGHT
public static final int GESTURE_SWIPE_UP_AND_RIGHT
The user has performed an up and right gesture on the touch screen.
Constant Value: 14 (0x0000000e)
GESTURE_UNKNOWN
public static final int GESTURE_UNKNOWN
The user has performed an unrecognized gesture on the touch screen. This gesture is only
dispatched when AccessibilityServiceInfo.FLAG_SEND_MOTION_EVENTS
is set.
Constant Value: 0 (0x00000000)
GLOBAL_ACTION_ACCESSIBILITY_ALL_APPS
public static final int GLOBAL_ACTION_ACCESSIBILITY_ALL_APPS
Action to show Launcher's all apps.
Constant Value: 14 (0x0000000e)
GLOBAL_ACTION_ACCESSIBILITY_BUTTON
public static final int GLOBAL_ACTION_ACCESSIBILITY_BUTTON
Action to trigger the Accessibility Button
Constant Value: 11 (0x0000000b)
GLOBAL_ACTION_ACCESSIBILITY_BUTTON_CHOOSER
public static final int GLOBAL_ACTION_ACCESSIBILITY_BUTTON_CHOOSER
Action to bring up the Accessibility Button's chooser menu
Constant Value: 12 (0x0000000c)
GLOBAL_ACTION_ACCESSIBILITY_SHORTCUT
public static final int GLOBAL_ACTION_ACCESSIBILITY_SHORTCUT
Action to trigger the Accessibility Shortcut. This shortcut has a hardware trigger and can be activated by holding down the two volume keys.
Constant Value: 13 (0x0000000d)
GLOBAL_ACTION_BACK
public static final int GLOBAL_ACTION_BACK
Action to go back.
Constant Value: 1 (0x00000001)
GLOBAL_ACTION_DISMISS_NOTIFICATION_SHADE
public static final int GLOBAL_ACTION_DISMISS_NOTIFICATION_SHADE
Action to dismiss the notification shade
Constant Value: 15 (0x0000000f)
GLOBAL_ACTION_DPAD_CENTER
public static final int GLOBAL_ACTION_DPAD_CENTER
Action to trigger dpad center keyevent.
Constant Value: 20 (0x00000014)
GLOBAL_ACTION_DPAD_DOWN
public static final int GLOBAL_ACTION_DPAD_DOWN
Action to trigger dpad down keyevent.
Constant Value: 17 (0x00000011)
GLOBAL_ACTION_DPAD_LEFT
public static final int GLOBAL_ACTION_DPAD_LEFT
Action to trigger dpad left keyevent.
Constant Value: 18 (0x00000012)
GLOBAL_ACTION_DPAD_RIGHT
public static final int GLOBAL_ACTION_DPAD_RIGHT
Action to trigger dpad right keyevent.
Constant Value: 19 (0x00000013)
GLOBAL_ACTION_DPAD_UP
public static final int GLOBAL_ACTION_DPAD_UP
Action to trigger dpad up keyevent.
Constant Value: 16 (0x00000010)
GLOBAL_ACTION_HOME
public static final int GLOBAL_ACTION_HOME
Action to go home.
Constant Value: 2 (0x00000002)
GLOBAL_ACTION_KEYCODE_HEADSETHOOK
public static final int GLOBAL_ACTION_KEYCODE_HEADSETHOOK
Action to send the KEYCODE_HEADSETHOOK KeyEvent, which is used to answer and hang up calls and play and stop media. Calling takes priority. If there is an incoming call, this action can be used to answer that call, and if there is an ongoing call, to hang up on that call.
Constant Value: 10 (0x0000000a)
GLOBAL_ACTION_LOCK_SCREEN
public static final int GLOBAL_ACTION_LOCK_SCREEN
Action to lock the screen
Constant Value: 8 (0x00000008)
GLOBAL_ACTION_MEDIA_PLAY_PAUSE
public static final int GLOBAL_ACTION_MEDIA_PLAY_PAUSE
Action to trigger media play/pause key event.
Constant Value: 22 (0x00000016)
GLOBAL_ACTION_MENU
public static final int GLOBAL_ACTION_MENU
Action to trigger menu key event.
Constant Value: 21 (0x00000015)
GLOBAL_ACTION_NOTIFICATIONS
public static final int GLOBAL_ACTION_NOTIFICATIONS
Action to open the notifications.
Constant Value: 4 (0x00000004)
GLOBAL_ACTION_POWER_DIALOG
public static final int GLOBAL_ACTION_POWER_DIALOG
Action to open the power long-press dialog.
Constant Value: 6 (0x00000006)
GLOBAL_ACTION_QUICK_SETTINGS
public static final int GLOBAL_ACTION_QUICK_SETTINGS
Action to open the quick settings.
Constant Value: 5 (0x00000005)
GLOBAL_ACTION_RECENTS
public static final int GLOBAL_ACTION_RECENTS
Action to toggle showing the overview of recent apps. Will fail on platforms that don't show recent apps.
Constant Value: 3 (0x00000003)
GLOBAL_ACTION_TAKE_SCREENSHOT
public static final int GLOBAL_ACTION_TAKE_SCREENSHOT
Action to take a screenshot
Constant Value: 9 (0x00000009)
GLOBAL_ACTION_TOGGLE_SPLIT_SCREEN
public static final int GLOBAL_ACTION_TOGGLE_SPLIT_SCREEN
Action to toggle docking the current app's window.
Note: It is effective only if it appears in getSystemActions()
.
Constant Value: 7 (0x00000007)
OVERLAY_RESULT_INTERNAL_ERROR
public static final int OVERLAY_RESULT_INTERNAL_ERROR
Result code indicating the overlay could not be attached due to an internal error and not because of problems with the input.
Constant Value: 1 (0x00000001)
OVERLAY_RESULT_INVALID
public static final int OVERLAY_RESULT_INVALID
Result code indicating the overlay could not be attached because the specified display or window id was invalid.
Constant Value: 2 (0x00000002)
OVERLAY_RESULT_SUCCESS
public static final int OVERLAY_RESULT_SUCCESS
Result code indicating the overlay was successfully attached.
Constant Value: 0 (0x00000000)
SERVICE_INTERFACE
public static final String SERVICE_INTERFACE
The Intent
that must be declared as handled by the service.
Constant Value: "android.accessibilityservice.AccessibilityService"
SERVICE_META_DATA
public static final String SERVICE_META_DATA
Name under which an AccessibilityService component publishes information
about itself. This meta-data must reference an XML resource containing an
<
tag. This is a sample XML file configuring an accessibility service:
accessibility-service
>
<accessibility-service android:accessibilityEventTypes="typeViewClicked|typeViewFocused" android:packageNames="foo.bar, foo.baz" android:accessibilityFeedbackType="feedbackSpoken" android:notificationTimeout="100" android:accessibilityFlags="flagDefault" android:settingsActivity="foo.bar.TestBackActivity" android:canRetrieveWindowContent="true" android:canRequestTouchExplorationMode="true" . . . />
Constant Value: "android.accessibilityservice"
SHOW_MODE_AUTO
public static final int SHOW_MODE_AUTO
Allow the system to control when the soft keyboard is shown.
Constant Value: 0 (0x00000000)
SHOW_MODE_HIDDEN
public static final int SHOW_MODE_HIDDEN
Never show the soft keyboard.
Constant Value: 1 (0x00000001)
SHOW_MODE_IGNORE_HARD_KEYBOARD
public static final int SHOW_MODE_IGNORE_HARD_KEYBOARD
Allow the soft keyboard to be shown, even if a hard keyboard is connected
Constant Value: 2 (0x00000002)
Public constructors
AccessibilityService
public AccessibilityService ()
Public methods
attachAccessibilityOverlayToDisplay
public void attachAccessibilityOverlayToDisplay (int displayId, SurfaceControl sc)
Attaches a SurfaceControl
containing an accessibility overlay to the
specified display. This type of overlay should be used for content that does not need to
track the location and size of Views in the currently active app e.g. service configuration
or general service UI.
Generally speaking, an accessibility overlay will be a View
. To embed
the View into a SurfaceControl
, create a SurfaceControlViewHost
and attach the View using SurfaceControlViewHost.setView(View, int, int)
. Then obtain the SurfaceControl by calling
viewHost.getSurfacePackage().getSurfaceControl()
.
To remove this overlay and free the associated resources, use
new SurfaceControl.Transaction().reparent(sc, null).apply();
.
If the specified overlay has already been attached to the specified display this method
does nothing. If the specified overlay has already been attached to a previous display this
function will transfer the overlay to the new display. Services can attach multiple overlays.
Use new SurfaceControl.Transaction().setLayer(sc, layer).apply();
. to
coordinate the order of the overlays on screen.
Parameters | |
---|---|
displayId |
int : the display to which the SurfaceControl should be attached. |
sc |
SurfaceControl : the SurfaceControl containing the overlay content
This value cannot be null . |
attachAccessibilityOverlayToDisplay
public final void attachAccessibilityOverlayToDisplay (int displayId, SurfaceControl sc, Executor executor, IntConsumer callback)
Attaches a SurfaceControl
containing an accessibility overlay to the
specified display. This type of overlay should be used for content that does not need to
track the location and size of Views in the currently active app e.g. service configuration
or general service UI.
Generally speaking, an accessibility overlay will be a View
. To embed
the View into a SurfaceControl
, create a SurfaceControlViewHost
and attach the View using SurfaceControlViewHost.setView(View, int, int)
. Then obtain the SurfaceControl by calling
viewHost.getSurfacePackage().getSurfaceControl()
.
To remove this overlay and free the associated resources, use
new SurfaceControl.Transaction().reparent(sc, null).apply();
.
If the specified overlay has already been attached to the specified display this method
does nothing. If the specified overlay has already been attached to a previous display this
function will transfer the overlay to the new display. Services can attach multiple overlays.
Use new SurfaceControl.Transaction().setLayer(sc, layer).apply();
. to
coordinate the order of the overlays on screen.
Parameters | |
---|---|
displayId |
int : the display to which the SurfaceControl should be attached. |
sc |
SurfaceControl : the SurfaceControl containing the overlay content
This value cannot be null . |
executor |
Executor : Executor on which to run the callback.
This value cannot be null .
Callback and listener events are dispatched through this
Executor , providing an easy way to control which thread is
used. To dispatch events through the main thread of your
application, you can use
Context.getMainExecutor() .
Otherwise, provide an Executor that dispatches to an appropriate thread. |
callback |
IntConsumer : The callback invoked when attaching the overlay has succeeded or failed. The
callback is a IntConsumer of the result status code.
This value cannot be null . |
attachAccessibilityOverlayToWindow
public final void attachAccessibilityOverlayToWindow (int accessibilityWindowId, SurfaceControl sc, Executor executor, IntConsumer callback)
Attaches an accessibility overlay SurfaceControl
to the specified
window. This method should be used when you want the overlay to move and resize as the parent
window moves and resizes.
Generally speaking, an accessibility overlay will be a View
. To embed
the View into a SurfaceControl
, create a SurfaceControlViewHost
and attach the View using SurfaceControlViewHost.setView(View, int, int)
. Then obtain the SurfaceControl by calling
viewHost.getSurfacePackage().getSurfaceControl()
.
To remove this overlay and free the associated resources, use
new SurfaceControl.Transaction().reparent(sc, null).apply();
.
If the specified overlay has already been attached to the specified window this method
does nothing. If the specified overlay has already been attached to a previous window this
function will transfer the overlay to the new window. Services can attach multiple overlays.
Use new SurfaceControl.Transaction().setLayer(sc, layer).apply();
. to
coordinate the order of the overlays on screen.
Parameters | |
---|---|
accessibilityWindowId |
int : The window id, from AccessibilityWindowInfo.getId() . |
sc |
SurfaceControl : the SurfaceControl containing the overlay content
This value cannot be null . |
executor |
Executor : Executor on which to run the callback.
This value cannot be null .
Callback and listener events are dispatched through this
Executor , providing an easy way to control which thread is
used. To dispatch events through the main thread of your
application, you can use
Context.getMainExecutor() .
Otherwise, provide an Executor that dispatches to an appropriate thread. |
callback |
IntConsumer : The callback invoked when attaching the overlay has succeeded or failed. The
callback is a IntConsumer of the result status code.
This value cannot be null . |
attachAccessibilityOverlayToWindow
public void attachAccessibilityOverlayToWindow (int accessibilityWindowId, SurfaceControl sc)
Attaches an accessibility overlay SurfaceControl
to the specified
window. This method should be used when you want the overlay to move and resize as the parent
window moves and resizes.
Generally speaking, an accessibility overlay will be a View
. To embed
the View into a SurfaceControl
, create a SurfaceControlViewHost
and attach the View using SurfaceControlViewHost.setView(View, int, int)
. Then obtain the SurfaceControl by calling
viewHost.getSurfacePackage().getSurfaceControl()
.
To remove this overlay and free the associated resources, use
new SurfaceControl.Transaction().reparent(sc, null).apply();
.
If the specified overlay has already been attached to the specified window this method
does nothing. If the specified overlay has already been attached to a previous window this
function will transfer the overlay to the new window. Services can attach multiple overlays.
Use new SurfaceControl.Transaction().setLayer(sc, layer).apply();
. to
coordinate the order of the overlays on screen.
Parameters | |
---|---|
accessibilityWindowId |
int : The window id, from AccessibilityWindowInfo.getId() . |
sc |
SurfaceControl : the SurfaceControl containing the overlay content
This value cannot be null . |
clearCache
public boolean clearCache ()
Clears the cache.
Returns | |
---|---|
boolean |
true if the cache was cleared |
clearCachedSubtree
public boolean clearCachedSubtree (AccessibilityNodeInfo node)
Invalidates node
and its subtree in the cache.
Parameters | |
---|---|
node |
AccessibilityNodeInfo : the node to invalidate.
This value cannot be null . |
Returns | |
---|---|
boolean |
true if the subtree rooted at node was invalidated. |
createDisplayContext
public Context createDisplayContext (Display display)
Returns a new Context
object from the current context but with resources
adjusted to match the metrics of display
. Each call to this method
returns a new instance of a context object. Context objects are not shared; however,
common state (such as the ClassLoader
and other resources for the same
configuration) can be shared, so the Context
itself is lightweight.
Note:
This Context
is not expected to be updated with new configuration if the
underlying display configuration changes and the cached Resources
it returns
could be stale. It is suggested to use
DisplayManager.DisplayListener
to listen for
changes and re-create an instance if necessary.
This Context
is not a UI context, do not use it to access UI components
or obtain a WindowManager
instance.
To obtain an instance of WindowManager
configured to show windows on the given
display, call createWindowContext(int, android.os.Bundle)
on the returned display context,
then call getSystemService(java.lang.String)
or getSystemService(java.lang.Class)
on the
returned window context.
Parameters | |
---|---|
display |
Display : The display to which the current context's resources are adjusted.
This value cannot be null . |
Returns | |
---|---|
Context |
This value cannot be null . |
createWindowContext
public Context createWindowContext (int type, Bundle options)
Creates a Context for a non-activity window.
A window context is a context that can be used to add non-activity windows, such as
WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY
. A window context
must be created from a context that has an associated Display
, such as
Activity
or a context created with
createDisplayContext(android.view.Display)
.
The window context is created with the appropriate Configuration
for the area of the
display that the windows created with it can occupy; it must be used when
inflating
views, such that they can be inflated with
proper Resources
.
Below is a sample code to add an application overlay window on the primary display:
... final DisplayManager dm = anyContext.getSystemService(DisplayManager.class); final Display primaryDisplay = dm.getDisplay(DEFAULT_DISPLAY); final Context windowContext = anyContext.createDisplayContext(primaryDisplay) .createWindowContext(TYPE_APPLICATION_OVERLAY, null); final View overlayView = Inflater.from(windowContext).inflate(someLayoutXml, null); // WindowManager.LayoutParams initialization ... // The types used in addView and createWindowContext must match. mParams.type = TYPE_APPLICATION_OVERLAY; ... windowContext.getSystemService(WindowManager.class).addView(overlayView, mParams);
This context's configuration and resources are adjusted to an area of the display where the windows with provided type will be added. Note that all windows associated with the same context will have an affinity and can only be moved together between different displays or areas on a display. If there is a need to add different window types, or non-associated windows, separate Contexts should be used.
Creating a window context is an expensive operation. Misuse of this API may lead to a huge performance drop. The best practice is to use the same window context when possible. An approach is to create one window context with specific window type and display and use it everywhere it's needed.
After Build.VERSION_CODES.S
, window context provides the capability to receive
configuration changes for existing token by overriding the
token
of the
WindowManager.LayoutParams
passed in
WindowManager.addView(View, LayoutParams)
. This is useful when an application needs
to attach its window to an existing activity for window token sharing use-case.
Note that the window context in Build.VERSION_CODES.R
didn't have this
capability. This is a no-op for the window context in Build.VERSION_CODES.R
.
final DisplayManager dm = anyContext.getSystemService(DisplayManager.class); final Display primaryDisplay = dm.getDisplay(DEFAULT_DISPLAY); final Context windowContext = anyContext.createWindowContext(primaryDisplay, TYPE_APPLICATION, null); // Get an existing token. final IBinder existingToken = activity.getWindow().getAttributes().token; // The types used in addView() and createWindowContext() must match. final WindowManager.LayoutParams params = new WindowManager.LayoutParams(TYPE_APPLICATION); params.token = existingToken; // After WindowManager#addView(), the server side will extract the provided token from // LayoutParams#token (existingToken in the sample code), and switch to propagate // configuration changes from the node associated with the provided token. windowContext.getSystemService(WindowManager.class).addView(overlayView, mParams);
After Build.VERSION_CODES.S
, window context provides the capability to listen to its
Configuration
changes by calling
registerComponentCallbacks(android.content.ComponentCallbacks)
, while other kinds of Context
will register the ComponentCallbacks
to its
Application context
. Note that window context only propagate
ComponentCallbacks.onConfigurationChanged(Configuration)
callback.
ComponentCallbacks.onLowMemory()
or other callbacks in ComponentCallbacks2
won't be invoked.
Note that using Application
or Service
context for
UI-related queries may result in layout or continuity issues on devices with variable screen
sizes (e.g. foldables) or in multi-window modes, since these non-UI contexts may not reflect
the Configuration
changes for the visual container.
Parameters | |
---|---|
type |
int : Value is WindowManager.LayoutParams.TYPE_BASE_APPLICATION , WindowManager.LayoutParams.TYPE_APPLICATION , WindowManager.LayoutParams.TYPE_APPLICATION_STARTING , WindowManager.LayoutParams.TYPE_DRAWN_APPLICATION , WindowManager.LayoutParams.TYPE_APPLICATION_PANEL , WindowManager.LayoutParams.TYPE_APPLICATION_MEDIA , WindowManager.LayoutParams.TYPE_APPLICATION_SUB_PANEL , WindowManager.LayoutParams.TYPE_APPLICATION_ATTACHED_DIALOG , android.view.WindowManager.LayoutParams.TYPE_APPLICATION_MEDIA_OVERLAY, android.view.WindowManager.LayoutParams.TYPE_APPLICATION_ABOVE_SUB_PANEL, WindowManager.LayoutParams.TYPE_STATUS_BAR , WindowManager.LayoutParams.TYPE_SEARCH_BAR , WindowManager.LayoutParams.TYPE_PHONE , WindowManager.LayoutParams.TYPE_SYSTEM_ALERT , android.view.WindowManager.LayoutParams.TYPE_KEYGUARD, WindowManager.LayoutParams.TYPE_TOAST , WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY , WindowManager.LayoutParams.TYPE_PRIORITY_PHONE , WindowManager.LayoutParams.TYPE_SYSTEM_DIALOG , WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG , WindowManager.LayoutParams.TYPE_SYSTEM_ERROR , WindowManager.LayoutParams.TYPE_INPUT_METHOD , WindowManager.LayoutParams.TYPE_INPUT_METHOD_DIALOG , WindowManager.LayoutParams.TYPE_WALLPAPER , android.view.WindowManager.LayoutParams.TYPE_STATUS_BAR_PANEL, android.view.WindowManager.LayoutParams.TYPE_SECURE_SYSTEM_OVERLAY, android.view.WindowManager.LayoutParams.TYPE_DRAG, android.view.WindowManager.LayoutParams.TYPE_STATUS_BAR_SUB_PANEL, android.view.WindowManager.LayoutParams.TYPE_POINTER, android.view.WindowManager.LayoutParams.TYPE_NAVIGATION_BAR, android.view.WindowManager.LayoutParams.TYPE_VOLUME_OVERLAY, android.view.WindowManager.LayoutParams.TYPE_BOOT_PROGRESS, android.view.WindowManager.LayoutParams.TYPE_INPUT_CONSUMER, android.view.WindowManager.LayoutParams.TYPE_NAVIGATION_BAR_PANEL, android.view.WindowManager.LayoutParams.TYPE_DISPLAY_OVERLAY, android.view.WindowManager.LayoutParams.TYPE_MAGNIFICATION_OVERLAY, WindowManager.LayoutParams.TYPE_PRIVATE_PRESENTATION , android.view.WindowManager.LayoutParams.TYPE_VOICE_INTERACTION, WindowManager.LayoutParams.TYPE_ACCESSIBILITY_OVERLAY , android.view.WindowManager.LayoutParams.TYPE_VOICE_INTERACTION_STARTING, android.view.WindowManager.LayoutParams.TYPE_DOCK_DIVIDER, android.view.WindowManager.LayoutParams.TYPE_QS_DIALOG, android.view.WindowManager.LayoutParams.TYPE_SCREENSHOT, android.view.WindowManager.LayoutParams.TYPE_PRESENTATION, WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY , android.view.WindowManager.LayoutParams.TYPE_ACCESSIBILITY_MAGNIFICATION_OVERLAY, android.view.WindowManager.LayoutParams.TYPE_NOTIFICATION_SHADE, or android.view.WindowManager.LayoutParams.TYPE_STATUS_BAR_ADDITIONAL |
options |
Bundle : This value may be null . |
Returns | |
---|---|
Context |
This value cannot be null . |
createWindowContext
public Context createWindowContext (Display display, int type, Bundle options)
Creates a Context
for a non-activity
window on the given
Display
.
Similar to createWindowContext(int, android.os.Bundle)
, but the display
is passed in,
instead of implicitly using the original Context's Display
.
Parameters | |
---|---|
display |
Display : This value cannot be null . |
type |
int : Value is WindowManager.LayoutParams.TYPE_BASE_APPLICATION , WindowManager.LayoutParams.TYPE_APPLICATION , WindowManager.LayoutParams.TYPE_APPLICATION_STARTING , WindowManager.LayoutParams.TYPE_DRAWN_APPLICATION , WindowManager.LayoutParams.TYPE_APPLICATION_PANEL , WindowManager.LayoutParams.TYPE_APPLICATION_MEDIA , WindowManager.LayoutParams.TYPE_APPLICATION_SUB_PANEL , WindowManager.LayoutParams.TYPE_APPLICATION_ATTACHED_DIALOG , android.view.WindowManager.LayoutParams.TYPE_APPLICATION_MEDIA_OVERLAY, android.view.WindowManager.LayoutParams.TYPE_APPLICATION_ABOVE_SUB_PANEL, WindowManager.LayoutParams.TYPE_STATUS_BAR , WindowManager.LayoutParams.TYPE_SEARCH_BAR , WindowManager.LayoutParams.TYPE_PHONE , WindowManager.LayoutParams.TYPE_SYSTEM_ALERT , android.view.WindowManager.LayoutParams.TYPE_KEYGUARD, WindowManager.LayoutParams.TYPE_TOAST , WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY , WindowManager.LayoutParams.TYPE_PRIORITY_PHONE , WindowManager.LayoutParams.TYPE_SYSTEM_DIALOG , WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG , WindowManager.LayoutParams.TYPE_SYSTEM_ERROR , WindowManager.LayoutParams.TYPE_INPUT_METHOD , WindowManager.LayoutParams.TYPE_INPUT_METHOD_DIALOG , WindowManager.LayoutParams.TYPE_WALLPAPER , android.view.WindowManager.LayoutParams.TYPE_STATUS_BAR_PANEL, android.view.WindowManager.LayoutParams.TYPE_SECURE_SYSTEM_OVERLAY, android.view.WindowManager.LayoutParams.TYPE_DRAG, android.view.WindowManager.LayoutParams.TYPE_STATUS_BAR_SUB_PANEL, android.view.WindowManager.LayoutParams.TYPE_POINTER, android.view.WindowManager.LayoutParams.TYPE_NAVIGATION_BAR, android.view.WindowManager.LayoutParams.TYPE_VOLUME_OVERLAY, android.view.WindowManager.LayoutParams.TYPE_BOOT_PROGRESS, android.view.WindowManager.LayoutParams.TYPE_INPUT_CONSUMER, android.view.WindowManager.LayoutParams.TYPE_NAVIGATION_BAR_PANEL, android.view.WindowManager.LayoutParams.TYPE_DISPLAY_OVERLAY, android.view.WindowManager.LayoutParams.TYPE_MAGNIFICATION_OVERLAY, WindowManager.LayoutParams.TYPE_PRIVATE_PRESENTATION , android.view.WindowManager.LayoutParams.TYPE_VOICE_INTERACTION, WindowManager.LayoutParams.TYPE_ACCESSIBILITY_OVERLAY , android.view.WindowManager.LayoutParams.TYPE_VOICE_INTERACTION_STARTING, android.view.WindowManager.LayoutParams.TYPE_DOCK_DIVIDER, android.view.WindowManager.LayoutParams.TYPE_QS_DIALOG, android.view.WindowManager.LayoutParams.TYPE_SCREENSHOT, android.view.WindowManager.LayoutParams.TYPE_PRESENTATION, WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY , android.view.WindowManager.LayoutParams.TYPE_ACCESSIBILITY_MAGNIFICATION_OVERLAY, android.view.WindowManager.LayoutParams.TYPE_NOTIFICATION_SHADE, or android.view.WindowManager.LayoutParams.TYPE_STATUS_BAR_ADDITIONAL |
options |
Bundle : This value may be null . |
Returns | |
---|---|
Context |
This value cannot be null . |
disableSelf
public final void disableSelf ()
Disables the service. After calling this method, the service will be disabled and settings will show that it is turned off.
dispatchGesture
public final boolean dispatchGesture (GestureDescription gesture, AccessibilityService.GestureResultCallback callback, Handler handler)
Dispatch a gesture to the touch screen. Any gestures currently in progress, whether from the user, this service, or another service, will be cancelled.
The gesture will be dispatched as if it were performed directly on the screen by a user, so the events may be affected by features such as magnification and explore by touch.
Note: In order to dispatch gestures, your service
must declare the capability by setting the
R.styleable.AccessibilityService_canPerformGestures
property in its meta-data. For more information, see
SERVICE_META_DATA
.
Since many apps do not appropriately support AccessibilityAction.ACTION_CLICK
,
if this action fails on an element that should be clickable, a service that is not a screen
reader may send a tap directly to the element as a fallback. The example below
demonstrates this fallback using the gesture dispatch APIs:
private void tap(PointF point) {
StrokeDescription tap = new StrokeDescription(path(point), 0,
ViewConfiguration.getTapTimeout());
GestureDescription.Builder builder = new GestureDescription.Builder();
builder.addStroke(tap);
dispatchGesture(builder.build(), null, null);
}
Parameters | |
---|---|
gesture |
GestureDescription : The gesture to dispatch
This value cannot be null . |
callback |
AccessibilityService.GestureResultCallback : The object to call back when the status of the gesture is known. If
null , no status is reported. |
handler |
Handler : The handler on which to call back the callback object. If
null , the object is called back on the service's main thread. |
Returns | |
---|---|
boolean |
true if the gesture is dispatched, false if not. |
findFocus
public AccessibilityNodeInfo findFocus (int focus)
Find the view that has the specified focus type. The search is performed across all windows.
Note: In order to access the windows your service has
to declare the capability to retrieve window content by setting the
R.styleable.AccessibilityService_canRetrieveWindowContent
property in its meta-data. For details refer to SERVICE_META_DATA
.
Also the service has to opt-in to retrieve the interactive windows by
setting the AccessibilityServiceInfo.FLAG_RETRIEVE_INTERACTIVE_WINDOWS
flag. Otherwise, the search will be performed only in the active window.
Note: If the view with AccessibilityNodeInfo.FOCUS_INPUT
is on an embedded view hierarchy which is embedded in a SurfaceView
via
SurfaceView.setChildSurfacePackage(SurfacePackage)
, there is a limitation that this API
won't be able to find the node for the view. It's because views don't know about
the embedded hierarchies. Instead, you could traverse all the nodes to find the
focus.
Parameters | |
---|---|
focus |
int : The focus to find. One of AccessibilityNodeInfo.FOCUS_INPUT or
AccessibilityNodeInfo.FOCUS_ACCESSIBILITY . |
Returns | |
---|---|
AccessibilityNodeInfo |
The node info of the focused view or null. |
getAccessibilityButtonController
public final AccessibilityButtonController getAccessibilityButtonController (int displayId)
Returns the controller of specified logical display for the accessibility button within the
system's navigation area. This instance may be used to query the accessibility button's
state and register listeners for interactions with and state changes for the accessibility
button when AccessibilityServiceInfo.FLAG_REQUEST_ACCESSIBILITY_BUTTON
is set.
Note: Not all devices are capable of displaying the accessibility button within a navigation area, and as such, use of this class should be considered only as an optional feature or shortcut on supported device implementations.
Parameters | |
---|---|
displayId |
int : The logic display id, use Display.DEFAULT_DISPLAY for default
display. |
Returns | |
---|---|
AccessibilityButtonController |
the accessibility button controller for this AccessibilityService
This value cannot be null . |
getAccessibilityButtonController
public final AccessibilityButtonController getAccessibilityButtonController ()
Returns the controller for the accessibility button within the system's navigation area.
This instance may be used to query the accessibility button's state and register listeners
for interactions with and state changes for the accessibility button when
AccessibilityServiceInfo.FLAG_REQUEST_ACCESSIBILITY_BUTTON
is set.
Note: Not all devices are capable of displaying the accessibility button within a navigation area, and as such, use of this class should be considered only as an optional feature or shortcut on supported device implementations.
Returns | |
---|---|
AccessibilityButtonController |
the accessibility button controller for this AccessibilityService
This value cannot be null . |
getBrailleDisplayController
public final BrailleDisplayController getBrailleDisplayController ()
Returns the BrailleDisplayController
which may be used to communicate with
refreshable Braille displays that provide USB or Bluetooth Braille display HID support.
Returns | |
---|---|
BrailleDisplayController |
This value cannot be null . |
getFingerprintGestureController
public final FingerprintGestureController getFingerprintGestureController ()
Get the controller for fingerprint gestures. This feature requires AccessibilityServiceInfo.CAPABILITY_CAN_REQUEST_FINGERPRINT_GESTURES
.
Note: The service must be connected before this method is called.
Requires Manifest.permission.USE_FINGERPRINT
Returns | |
---|---|
FingerprintGestureController |
The controller for fingerprint gestures, or null if gestures are unavailable. |
getInputMethod
public final InputMethod getInputMethod ()
Returns the InputMethod instance after the system calls onCreateInputMethod()
,
which may be used to input text or get editable text selection change notifications. It will
return null if the accessibility service doesn't set the
AccessibilityServiceInfo.FLAG_INPUT_METHOD_EDITOR
flag or the system doesn't call
onCreateInputMethod()
.
Returns | |
---|---|
InputMethod |
the InputMethod instance |
getMagnificationController
public final AccessibilityService.MagnificationController getMagnificationController ()
Returns the magnification controller, which may be used to query and modify the state of display magnification.
Note: In order to control magnification, your service
must declare the capability by setting the
R.styleable.AccessibilityService_canControlMagnification
property in its meta-data. For more information, see
SERVICE_META_DATA
.
Returns | |
---|---|
AccessibilityService.MagnificationController |
the magnification controller
This value cannot be null . |
getRootInActiveWindow
public AccessibilityNodeInfo getRootInActiveWindow ()
Gets the root node in the currently active window if this service can retrieve window content. The active window is the one that the user is currently touching or the window with input focus, if the user is not touching any window. It could be from any logical display.
Note: In order to access the root node your service has
to declare the capability to retrieve window content by setting the
R.styleable.AccessibilityService_canRetrieveWindowContent
property in its meta-data. For details refer to SERVICE_META_DATA
.
Returns | |
---|---|
AccessibilityNodeInfo |
The root node if this service can retrieve window content. |
getRootInActiveWindow
public AccessibilityNodeInfo getRootInActiveWindow (int prefetchingStrategy)
Gets the root node in the currently active window if this service can retrieve window content. The active window is the one that the user is currently touching or the window with input focus, if the user is not touching any window. It could be from any logical display.
Parameters | |
---|---|
prefetchingStrategy |
int : the prefetching strategy.
Value is either 0 or a combination of AccessibilityNodeInfo.FLAG_PREFETCH_ANCESTORS , AccessibilityNodeInfo.FLAG_PREFETCH_SIBLINGS , AccessibilityNodeInfo.FLAG_PREFETCH_DESCENDANTS_HYBRID , AccessibilityNodeInfo.FLAG_PREFETCH_DESCENDANTS_DEPTH_FIRST , AccessibilityNodeInfo.FLAG_PREFETCH_DESCENDANTS_BREADTH_FIRST , and AccessibilityNodeInfo.FLAG_PREFETCH_UNINTERRUPTIBLE |
Returns | |
---|---|
AccessibilityNodeInfo |
The root node if this service can retrieve window content.
This value may be null . |
getServiceInfo
public final AccessibilityServiceInfo getServiceInfo ()
Gets the an AccessibilityServiceInfo
describing this
AccessibilityService
. This method is useful if one wants
to change some of the dynamically configurable properties at
runtime.
Returns | |
---|---|
AccessibilityServiceInfo |
The accessibility service info. |
See also:
getSoftKeyboardController
public final AccessibilityService.SoftKeyboardController getSoftKeyboardController ()
Returns the soft keyboard controller, which may be used to query and modify the soft keyboard show mode.
Returns | |
---|---|
AccessibilityService.SoftKeyboardController |
the soft keyboard controller
This value cannot be null . |
getSystemActions
public final List<AccessibilityNodeInfo.AccessibilityAction> getSystemActions ()
Returns a list of system actions available in the system right now.
System actions that correspond to the global action constants will have matching action IDs.
For example, an with id GLOBAL_ACTION_BACK
will perform the back action.
These actions should be called by performGlobalAction(int)
.
Returns | |
---|---|
List<AccessibilityNodeInfo.AccessibilityAction> |
A list of available system actions.
This value cannot be null . |
getSystemService
public Object getSystemService (String name)
Return the handle to a system-level service by name. The class of the returned object varies by the requested name. Currently available names are:
-
WINDOW_SERVICE
("window") - The top-level window manager in which you can place custom
windows. The returned object is a
WindowManager
. Must only be obtained from a visual context such as Activity or a Context created withcreateWindowContext(int, android.os.Bundle)
, which are adjusted to the configuration and visual bounds of an area on screen. -
LAYOUT_INFLATER_SERVICE
("layout_inflater") - A
LayoutInflater
for inflating layout resources in this context. Must only be obtained from a visual context such as Activity or a Context created withcreateWindowContext(int, android.os.Bundle)
, which are adjusted to the configuration and visual bounds of an area on screen. -
ACTIVITY_SERVICE
("activity") - A
ActivityManager
for interacting with the global activity state of the system. -
WALLPAPER_SERVICE
("wallpaper") - A
WallpaperService
for accessing wallpapers in this context. Must only be obtained from a visual context such as Activity or a Context created withcreateWindowContext(int, android.os.Bundle)
, which are adjusted to the configuration and visual bounds of an area on screen. -
POWER_SERVICE
("power") - A
PowerManager
for controlling power management. -
ALARM_SERVICE
("alarm") - A
AlarmManager
for receiving intents at the time of your choosing. -
NOTIFICATION_SERVICE
("notification") - A
NotificationManager
for informing the user of background events. -
KEYGUARD_SERVICE
("keyguard") - A
KeyguardManager
for controlling keyguard. -
LOCATION_SERVICE
("location") - A
LocationManager
for controlling location (e.g., GPS) updates. -
SEARCH_SERVICE
("search") - A
SearchManager
for handling search. -
VIBRATOR_MANAGER_SERVICE
("vibrator_manager") - A
VibratorManager
for accessing the device vibrators, interacting with individual ones and playing synchronized effects on multiple vibrators. -
VIBRATOR_SERVICE
("vibrator") - A
Vibrator
for interacting with the vibrator hardware. -
CONNECTIVITY_SERVICE
("connectivity") - A
ConnectivityManager
for handling management of network connections. -
IPSEC_SERVICE
("ipsec") - A
IpSecManager
for managing IPSec on sockets and networks. -
WIFI_SERVICE
("wifi") - A
WifiManager
for management of Wi-Fi connectivity. On releases before Android 7, it should only be obtained from an application context, and not from any other derived context to avoid memory leaks within the calling process. -
WIFI_AWARE_SERVICE
("wifiaware") - A
WifiAwareManager
for management of Wi-Fi Aware discovery and connectivity. -
WIFI_P2P_SERVICE
("wifip2p") - A
WifiP2pManager
for management of Wi-Fi Direct connectivity. -
INPUT_METHOD_SERVICE
("input_method") - An
InputMethodManager
for management of input methods. -
UI_MODE_SERVICE
("uimode") - An
UiModeManager
for controlling UI modes. -
DOWNLOAD_SERVICE
("download") - A
DownloadManager
for requesting HTTP downloads -
BATTERY_SERVICE
("batterymanager") - A
BatteryManager
for managing battery state -
JOB_SCHEDULER_SERVICE
("taskmanager") - A
JobScheduler
for managing scheduled tasks -
NETWORK_STATS_SERVICE
("netstats") - A
NetworkStatsManager
for querying network usage statistics. -
HARDWARE_PROPERTIES_SERVICE
("hardware_properties") - A
HardwarePropertiesManager
for accessing hardware properties. -
DOMAIN_VERIFICATION_SERVICE
("domain_verification") - A
DomainVerificationManager
for accessing web domain approval state. -
DISPLAY_HASH_SERVICE
("display_hash") - A
DisplayHashManager
for management of display hashes. -
ERROR(/#AUTHENTICATION_POLICY_SERVICE)
("authentication_policy") - A
ERROR(/android.security.authenticationpolicy.AuthenticationPolicyManager)
for managing authentication related policies on the device.
Note: System services obtained via this API may be closely associated with the Context in which they are obtained from. In general, do not share the service objects between various different contexts (Activities, Applications, Services, Providers, etc.)
Note: Instant apps, for which PackageManager.isInstantApp()
returns true,
don't have access to the following system services: DEVICE_POLICY_SERVICE
,
FINGERPRINT_SERVICE
, KEYGUARD_SERVICE
, SHORTCUT_SERVICE
,
USB_SERVICE
, WALLPAPER_SERVICE
, WIFI_P2P_SERVICE
,
WIFI_SERVICE
, WIFI_AWARE_SERVICE
. For these services this method will
return null
. Generally, if you are running as an instant app you should always
check whether the result of this method is null
.
Note: When implementing this method, keep in mind that new services can be added on newer
Android releases, so if you're looking for just the explicit names mentioned above, make sure
to return null
when you don't recognize the name — if you throw a
RuntimeException
exception instead, your app might break on new Android releases.
Returns | |
---|---|
Object |
The service or null if the name does not exist. |
getTouchInteractionController
public final TouchInteractionController getTouchInteractionController (int displayId)
Returns the touch interaction controller for the specified logical display, which may be used
to detect gestures and otherwise control touch interactions. If
AccessibilityServiceInfo.FLAG_REQUEST_TOUCH_EXPLORATION_MODE
is disabled the
controller's methods will have no effect.
Parameters | |
---|---|
displayId |
int : The logical display id, use Display.DEFAULT_DISPLAY for default
display. |
Returns | |
---|---|
TouchInteractionController |
the TouchExploration controller
This value cannot be null . |
getWindows
public List<AccessibilityWindowInfo> getWindows ()
Gets the windows on the screen of the default display. This method returns only the windows that a sighted user can interact with, as opposed to all windows. For example, if there is a modal dialog shown and the user cannot touch anything behind it, then only the modal window will be reported (assuming it is the top one). For convenience the returned windows are ordered in a descending layer order, which is the windows that are on top are reported first. Since the user can always interact with the window that has input focus by typing, the focused window is always returned (even if covered by a modal window).
Note: In order to access the windows your service has
to declare the capability to retrieve window content by setting the
R.styleable.AccessibilityService_canRetrieveWindowContent
property in its meta-data. For details refer to SERVICE_META_DATA
.
Also the service has to opt-in to retrieve the interactive windows by
setting the AccessibilityServiceInfo.FLAG_RETRIEVE_INTERACTIVE_WINDOWS
flag.
Returns | |
---|---|
List<AccessibilityWindowInfo> |
The windows if there are windows and the service is can retrieve them, otherwise an empty list. |
getWindowsOnAllDisplays
public final SparseArray<List<AccessibilityWindowInfo>> getWindowsOnAllDisplays ()
Gets the windows on the screen of all displays. This method returns only the windows that a sighted user can interact with, as opposed to all windows. For example, if there is a modal dialog shown and the user cannot touch anything behind it, then only the modal window will be reported (assuming it is the top one). For convenience the returned windows are ordered in a descending layer order, which is the windows that are on top are reported first. Since the user can always interact with the window that has input focus by typing, the focused window is always returned (even if covered by a modal window).
Note: In order to access the windows your service has
to declare the capability to retrieve window content by setting the
R.styleable.AccessibilityService_canRetrieveWindowContent
property in its meta-data. For details refer to SERVICE_META_DATA
.
Also the service has to opt-in to retrieve the interactive windows by
setting the AccessibilityServiceInfo.FLAG_RETRIEVE_INTERACTIVE_WINDOWS
flag.
Returns | |
---|---|
SparseArray<List<AccessibilityWindowInfo>> |
The windows of all displays if there are windows and the service is can retrieve
them, otherwise an empty list. The key of SparseArray is display ID.
This value cannot be null . |
isCacheEnabled
public boolean isCacheEnabled ()
Returns true
if the cache is enabled.
Returns | |
---|---|
boolean |
isNodeInCache
public boolean isNodeInCache (AccessibilityNodeInfo node)
Checks if node
is in the cache.
Parameters | |
---|---|
node |
AccessibilityNodeInfo : the node to check.
This value cannot be null . |
Returns | |
---|---|
boolean |
true if node is in the cache. |
onAccessibilityEvent
public abstract void onAccessibilityEvent (AccessibilityEvent event)
Callback for AccessibilityEvent
s.
Parameters | |
---|---|
event |
AccessibilityEvent : The new event. This event is owned by the caller and cannot be used after
this method returns. Services wishing to use the event after this method returns should
make a copy. |
onBind
public final IBinder onBind (Intent intent)
Implement to return the implementation of the internal accessibility service interface.
Parameters | |
---|---|
intent |
Intent : The Intent that was used to bind to this service,
as given to Context.bindService . Note that any extras that were included with
the Intent at that point will not be seen here. |
Returns | |
---|---|
IBinder |
Return an IBinder through which clients can call on to the service. |
onCreateInputMethod
public InputMethod onCreateInputMethod ()
The default implementation returns our default InputMethod
. Subclasses can override
it to provide their own customized version. Accessibility services need to set the
AccessibilityServiceInfo.FLAG_INPUT_METHOD_EDITOR
flag to use input method APIs.
Returns | |
---|---|
InputMethod |
the InputMethod.
This value cannot be null . |
onGesture
public boolean onGesture (AccessibilityGestureEvent gestureEvent)
Called by the system when the user performs a specific gesture on the specific touch screen.
Note: To receive gestures an accessibility service must
request that the device is in touch exploration mode by setting the
AccessibilityServiceInfo.FLAG_REQUEST_TOUCH_EXPLORATION_MODE
flag.
Note: The default implementation calls onGesture(int)
when the
touch screen is default display.
Parameters | |
---|---|
gestureEvent |
AccessibilityGestureEvent : The information of gesture.
This value cannot be null . |
Returns | |
---|---|
boolean |
Whether the gesture was handled. |
onInterrupt
public abstract void onInterrupt ()
Callback for interrupting the accessibility feedback.
onMotionEvent
public void onMotionEvent (MotionEvent event)
Callback that allows an accessibility service to observe generic MotionEvent
s.
Prefer TouchInteractionController
to observe and control touchscreen events,
including touch gestures. If this or any enabled service is using
AccessibilityServiceInfo.FLAG_REQUEST_TOUCH_EXPLORATION_MODE
then
onMotionEvent(MotionEvent)
will not receive touchscreen events.
Note: The service must first request to listen to events using
AccessibilityServiceInfo.setMotionEventSources
.
MotionEvent
s from sources in AccessibilityServiceInfo.getMotionEventSources()
are not sent to the rest of the system. To stop listening to events from a given source, call
AccessibilityServiceInfo.setMotionEventSources
with that source removed.
Parameters | |
---|---|
event |
MotionEvent : The event to be processed.
This value cannot be null . |
onSystemActionsChanged
public void onSystemActionsChanged ()
This is called when the system action list is changed.
performGlobalAction
public final boolean performGlobalAction (int action)
Performs a global action. Such an action can be performed at any moment regardless of the current application or user location in that application. For example going back, going home, opening recents, etc.
Note: The global action ids themselves give no information about the current availability
of their corresponding actions. To determine if a global action is available, use
getSystemActions()
Parameters | |
---|---|
action |
int : The action to perform. |
Returns | |
---|---|
boolean |
Whether the action was successfully performed. Perform actions using ids like the id constants referenced below: |
setAccessibilityFocusAppearance
public void setAccessibilityFocusAppearance (int strokeWidth, int color)
Sets the strokeWidth and color of the accessibility focus rectangle.
Note: This setting persists until this or another active AccessibilityService changes it or the device reboots.
Parameters | |
---|---|
strokeWidth |
int : The stroke width of the rectangle in pixels.
Setting this value to zero results in no focus rectangle being drawn. |
color |
int : The color of the rectangle. |
setAnimationScale
public void setAnimationScale (float scale)
Sets the system settings values that control the scaling factor for animations. The scale
controls the animation playback speed for animations that respect these settings. Animations
that do not respect the settings values will not be affected by this function. A lower scale
value results in a faster speed. A value of 0
disables animations entirely. When
animations are disabled services receive window change events more quickly which can reduce
the potential by confusion by reducing the time during which windows are in transition.
Parameters | |
---|---|
scale |
float : The scaling factor for all animations. |
setCacheEnabled
public boolean setCacheEnabled (boolean enabled)
Sets the cache status.
If enabled
, enable the cache and prefetching. Otherwise, disable the cache
and prefetching.
Note: By default the cache is enabled.
Parameters | |
---|---|
enabled |
boolean : whether to enable or disable the cache. |
Returns | |
---|---|
boolean |
true if the cache and connection are not null, so the cache status is set. |
setGestureDetectionPassthroughRegion
public void setGestureDetectionPassthroughRegion (int displayId, Region region)
When AccessibilityServiceInfo.FLAG_REQUEST_TOUCH_EXPLORATION_MODE
is enabled, this
function requests that touch interactions starting in the specified region of the screen
bypass the gesture detector. There can only be one gesture detection passthrough region per
display. Requesting a new gesture detection passthrough region clears the existing one. To
disable this passthrough and return to the original behavior, pass in an empty region. When
AccessibilityServiceInfo.FLAG_REQUEST_TOUCH_EXPLORATION_MODE
is disabled this
function has no effect.
Parameters | |
---|---|
displayId |
int : The display on which to set this region. |
region |
Region : the region of the screen.
This value cannot be null . |
setServiceInfo
public final void setServiceInfo (AccessibilityServiceInfo info)
Sets the AccessibilityServiceInfo
that describes this service.
Note: You can call this method any time but the info will be picked up after the system has bound to this service and when this method is called thereafter.
Parameters | |
---|---|
info |
AccessibilityServiceInfo : The info. |
setTouchExplorationPassthroughRegion
public void setTouchExplorationPassthroughRegion (int displayId, Region region)
When AccessibilityServiceInfo.FLAG_REQUEST_TOUCH_EXPLORATION_MODE
is enabled, this
function requests that touch interactions starting in the specified region of the screen
bypass the touch explorer and go straight to the view hierarchy. There can only be one touch
exploration passthrough region per display. Requesting a new touch explorationpassthrough
region clears the existing one. To disable this passthrough and return to the original
behavior, pass in an empty region. When AccessibilityServiceInfo.FLAG_REQUEST_TOUCH_EXPLORATION_MODE
is disabled this function has
no effect.
Parameters | |
---|---|
displayId |
int : The display on which to set this region. |
region |
Region : the region of the screen .
This value cannot be null . |
takeScreenshot
public void takeScreenshot (int displayId, Executor executor, AccessibilityService.TakeScreenshotCallback callback)
Takes a screenshot of the specified display and returns it via an
AccessibilityService.ScreenshotResult
. You can use Bitmap.wrapHardwareBuffer
to construct the bitmap from the ScreenshotResult's payload.
Note: In order to take screenshot your service has
to declare the capability to take screenshot by setting the
R.styleable.AccessibilityService_canTakeScreenshot
property in its meta-data. For details refer to SERVICE_META_DATA
.
Parameters | |
---|---|
displayId |
int : The logic display id, must be Display.DEFAULT_DISPLAY for
default display. |
executor |
Executor : Executor on which to run the callback.
This value cannot be null .
Callback and listener events are dispatched through this
Executor , providing an easy way to control which thread is
used. To dispatch events through the main thread of your
application, you can use
Context.getMainExecutor() .
Otherwise, provide an Executor that dispatches to an appropriate thread. |
callback |
AccessibilityService.TakeScreenshotCallback : The callback invoked when taking screenshot has succeeded or failed.
See TakeScreenshotCallback for details.
This value cannot be null . |
takeScreenshotOfWindow
public void takeScreenshotOfWindow (int accessibilityWindowId, Executor executor, AccessibilityService.TakeScreenshotCallback callback)
Takes a screenshot of the specified window and returns it via an
AccessibilityService.ScreenshotResult
. You can use Bitmap.wrapHardwareBuffer
to construct the bitmap from the ScreenshotResult's payload.
Note: In order to take screenshots your service has
to declare the capability to take screenshot by setting the
R.styleable.AccessibilityService_canTakeScreenshot
property in its meta-data. For details refer to SERVICE_META_DATA
.
Both this method and takeScreenshot(int, Executor, TakeScreenshotCallback)
can be used for machine learning-based visual
screen understanding. Use takeScreenshotOfWindow
if your target window might be
visually underneath an accessibility overlay (from your or another accessibility service) in
order to capture the window contents without the screenshot being covered by the overlay
contents drawn on the screen.
Parameters | |
---|---|
accessibilityWindowId |
int : The window id, from AccessibilityWindowInfo.getId() . |
executor |
Executor : Executor on which to run the callback.
This value cannot be null .
Callback and listener events are dispatched through this
Executor , providing an easy way to control which thread is
used. To dispatch events through the main thread of your
application, you can use
Context.getMainExecutor() .
Otherwise, provide an Executor that dispatches to an appropriate thread. |
callback |
AccessibilityService.TakeScreenshotCallback : The callback invoked when taking screenshot has succeeded or failed.
See TakeScreenshotCallback for details.
This value cannot be null . |
Protected methods
onGesture
protected boolean onGesture (int gestureId)
This method was deprecated
in API level 30.
Override onGesture(android.accessibilityservice.AccessibilityGestureEvent)
instead.
Called by onGesture(android.accessibilityservice.AccessibilityGestureEvent)
when the user performs a specific
gesture on the default display.
Note: To receive gestures an accessibility service must
request that the device is in touch exploration mode by setting the
AccessibilityServiceInfo.FLAG_REQUEST_TOUCH_EXPLORATION_MODE
flag.
Parameters | |
---|---|
gestureId |
int : The unique id of the performed gesture. |
Returns | |
---|---|
boolean |
Whether the gesture was handled. |
See also:
GESTURE_SWIPE_UP
GESTURE_SWIPE_UP_AND_LEFT
GESTURE_SWIPE_UP_AND_DOWN
GESTURE_SWIPE_UP_AND_RIGHT
GESTURE_SWIPE_DOWN
GESTURE_SWIPE_DOWN_AND_LEFT
GESTURE_SWIPE_DOWN_AND_UP
GESTURE_SWIPE_DOWN_AND_RIGHT
GESTURE_SWIPE_LEFT
GESTURE_SWIPE_LEFT_AND_UP
GESTURE_SWIPE_LEFT_AND_RIGHT
GESTURE_SWIPE_LEFT_AND_DOWN
GESTURE_SWIPE_RIGHT
GESTURE_SWIPE_RIGHT_AND_UP
GESTURE_SWIPE_RIGHT_AND_LEFT
GESTURE_SWIPE_RIGHT_AND_DOWN
onKeyEvent
protected boolean onKeyEvent (KeyEvent event)
Callback that allows an accessibility service to observe the key events before they are passed to the rest of the system. This means that the events are first delivered here before they are passed to the device policy, the input method, or applications.
Note: It is important that key events are handled in such a way that the event stream that would be passed to the rest of the system is well-formed. For example, handling the down event but not the up event and vice versa would generate an inconsistent event stream.
Note: The key events delivered in this method are copies and modifying them will have no effect on the events that will be passed to the system. This method is intended to perform purely filtering functionality.
Parameters | |
---|---|
event |
KeyEvent : The event to be processed. This event is owned by the caller and cannot be used
after this method returns. Services wishing to use the event after this method returns should
make a copy. |
Returns | |
---|---|
boolean |
If true then the event will be consumed and not delivered to applications, otherwise it will be delivered as usual. |
onServiceConnected
protected void onServiceConnected ()
This method is a part of the AccessibilityService
lifecycle and is
called after the system has successfully bound to the service. If is
convenient to use this method for setting the AccessibilityServiceInfo
.
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Last updated 2024-12-18 UTC.