@ohos.accessibility (Accessibility)

The Accessibility module implements the accessibility functions, including obtaining the accessibility application list, accessibility application enabled status, and captions configuration.

NOTE

• The initial APIs of this module are supported since API version 7. Newly added APIs will be marked with a superscript to indicate their earliest API version.

Modules to Import

import { accessibility } from '@kit.AccessibilityKit';

AbilityState

type AbilityState = ‘enable’|‘disable’|‘install’

Enumerates the states of an accessibility application.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Type	Description
‘enable’	The accessibility application is enabled.
‘disable’	The accessibility application is disabled.
‘install’	The accessibility application has been installed.

AbilityType

Enumerates the types of accessibility applications.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Name	Description
audible	The accessibility application provides audible feedback.
generic	The accessibility application provides generic feedback.
haptic	The accessibility application provides haptic feedback.
spoken	The accessibility application provides spoken feedback.
visual	The accessibility application provides visual feedback.
all9+	All the preceding types.

AccessibilityAbilityInfo

Provides information about an accessibility application.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Properties

Name	Type	Readable	Writable	Description
id	string	Yes	No	Ability ID.
name	string	Yes	No	Ability name.
bundleName	string	Yes	No	Bundle name.
targetBundleNames9+	Array<string>	Yes	No	Name of the target bundle.
abilityTypes	Array<AbilityType>	Yes	No	Accessibility application type.
capabilities	Array<Capability>	Yes	No	Capabilities list of the accessibility application.
description	string	Yes	No	Description of the accessibility application.
eventTypes	Array<EventType>	Yes	No	List of events that the accessibility application focuses on.
needHide12+	boolean	Yes	No	Whether the auxiliary application is hidden in the list of installed extended services. The value true means the auxiliary application is hidden, and the value false means the opposite.
label12+	string	Yes	No	Name of the application in the extended service list.

Action

type Action = ‘accessibilityFocus’|‘clearAccessibilityFocus’|‘focus’|‘clearFocus’|‘clearSelection’| ‘click’|‘longClick’|‘cut’|‘copy’|‘paste’|‘select’|‘setText’|‘delete’| ‘scrollForward’|‘scrollBackward’|‘setSelection’|‘setCursorPosition’|‘home’| ‘back’|‘recentTask’|‘notificationCenter’|‘controlCenter’|‘common’

Target actions supported by the application. The target actions for which parameters need to be set have been specified in the description of the following table.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Type	Description
‘click’	Clicking.
‘longClick’	Long pressing.
‘scrollForward’	Scrolling forward.
‘scrollBackward’	Scrolling backward.
‘focus’	Obtaining the focus.
‘clearFocus’	Clearing focus.
‘clearSelection’	Clearing selection. Not supported yet.
‘accessibilityFocus’	Obtaining the accessibility focus.
‘clearAccessibilityFocus’	Clearing the accessibility focus.
‘cut’	Cutting.
‘copy’	Copying.
‘paste’	Pasting.
‘select’	Selecting.
‘setText’	Setting text. You need to set the setText parameter.
‘delete’	Delete. Not supported yet.
‘setSelection’	Selecting. You need to set the selectTextBegin, selectTextEnd and selectTextInForWard parameters.
‘common’	Common actions used in auto-focusing and auto-broadcasting.
‘home’	Returning to the home screen.
‘back’	Returning to the previous screen.
‘recentTask’	Opening a recent task.
‘notificationCenter’	Opening the notification bar.
‘controlCenter’	Opening the control center.
‘setCursorPosition’	Setting cursor location. You need to set the offset parameter.

Capability

type Capability = ‘retrieve’|‘touchGuide’|‘keyEventObserver’|‘zoom’|‘gesture’

Enumerates the capabilities of an accessibility application.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Type	Description
‘retrieve’	Capability to retrieve the window content.
‘touchGuide’	Capability of touch guide mode.
‘keyEventObserver’	Capability to filter key events.
‘zoom’	Capability to control the display zoom level. Not supported currently.
‘gesture’	Capability to perform gesture actions.

CaptionsFontEdgeType⁸⁺

type CaptionsFontEdgeType = ‘none’|‘raised’|‘depressed’|‘uniform’|‘dropShadow’

Enumerates the font edge types of captions.

System capability: SystemCapability.BarrierFree.Accessibility.Hearing

Type	Description
‘none’	No effect.
‘raised’	Raised effect.
‘depressed’	Depressed effect.
‘uniform’	Uniform effect.
‘dropShadow’	Drop shadow effect.

CaptionsFontFamily⁸⁺

type CaptionsFontFamily = ‘default’|‘monospacedSerif’|‘serif’|‘monospacedSansSerif’| ‘sansSerif’|‘casual’|‘cursive’|‘smallCapitals’

Enumerates the font families of captions.

System capability: SystemCapability.BarrierFree.Accessibility.Hearing

Name	Description
‘default’	Default font family.
‘monospacedSerif’	Monospaced Serif fonts, which use the same width for each character.
‘serif’	Serif fonts.
‘monospacedSansSerif’	Monospaced Sans Serif fonts, which use the same width for each character.
‘sansSerif’	Sans Serif fonts.
‘casual’	Casual fonts.
‘cursive’	Cursive fonts.
‘smallCapitals’	Small caps fonts.

CaptionsStyle⁸⁺

Describes the style of captions.

System capability: SystemCapability.BarrierFree.Accessibility.Hearing

Name	Type	Readable	Writable	Description
fontFamily	CaptionsFontFamily	Yes	No	Font family of captions.
fontScale	number	Yes	No	Font scale factor of captions, in percentage. The value ranges from 1 to 200.
fontColor	number |string	Yes	No	Font color of captions. For example, red corresponds to #FF0000.
fontEdgeType	CaptionsFontEdgeType	Yes	No	Font edge type of captions.
backgroundColor	number |string	Yes	No	Background color of captions. For example, red corresponds to #FF0000.
windowColor	number |string	Yes	No	Window color of captions. For example, red corresponds to #FF0000.

CaptionsManager⁸⁺

Implements configuration management for captions. Before calling any API of CaptionsManager, you must use the accessibility.getCaptionsManager() API to obtain a CaptionsManager instance.

System capability: SystemCapability.BarrierFree.Accessibility.Hearing

Properties

Name	Type	Readable	Writable	Description
enabled	boolean	Yes	No	Whether to enable captions configuration.
style	CaptionsStyle	Yes	No	Style of captions.

For a boolean return value, True means that the feature is enabled, and False means the opposite.

on(‘enableChange’)^(deprecated)

on(type: ‘enableChange’, callback: Callback<boolean>): void;

Enables listening for the enabled status changes of captions configuration. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 12. Related features are no longer available in the system.

System capability: SystemCapability.BarrierFree.Accessibility.Hearing

Parameters

Name	Type	Mandatory	Description
type	string	Yes	Listening type, which is set to ‘enableChange’ in this API.
callback	Callback<boolean>	Yes	Callback invoked when the enabled status of captions configuration changes.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';

let captionsManager = accessibility.getCaptionsManager();
captionsManager.on('enableChange', (data: boolean) => {
  console.info(`subscribe caption manager enable state change, result: ${JSON.stringify(data)}`);
})

on(‘styleChange’)^(deprecated)

on(type: ‘styleChange’, callback: Callback<CaptionsStyle>): void;

Enables listening for captions style changes. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 12. Related features are no longer available in the system.

System capability: SystemCapability.BarrierFree.Accessibility.Hearing

Parameters

Name	Type	Mandatory	Description
type	string	Yes	Listening type, which is set to ‘styleChange’ in this API.
callback	Callback<CaptionsStyle>	Yes	Callback invoked when the style of captions changes.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';

let captionsManager = accessibility.getCaptionsManager();

captionsManager.on('styleChange', (data: accessibility.CaptionsStyle) => {
  console.info(`subscribe caption manager style state change, result: ${JSON.stringify(data)}`);
});

off(‘enableChange’)^(deprecated)

off(type: ‘enableChange’, callback?: Callback<boolean>): void;

Disables listening for the enabled status changes of captions configuration. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 12. Related features are no longer available in the system.

System capability: SystemCapability.BarrierFree.Accessibility.Hearing

Parameters

Name	Type	Mandatory	Description
type	string	Yes	Listening type, which is set to ‘enableChange’ in this API.
callback	Callback<boolean>	No	Callback used for disable listening. The value must be the same as the value of callback in on(‘enableChange’). If this parameter is not specified, listening will be disabled for all callbacks corresponding to the specified type.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';

let captionsManager = accessibility.getCaptionsManager();

captionsManager.off('enableChange', (data: boolean) => {
  console.info(`Unsubscribe caption manager enable state change, result: ${JSON.stringify(data)}`);
});

off(‘styleChange’)^(deprecated)

off(type: ‘styleChange’, callback?: Callback<CaptionsStyle>): void;

Disables listening for captions style changes. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 12. Related features are no longer available in the system.

System capability: SystemCapability.BarrierFree.Accessibility.Hearing

Parameters

Name	Type	Mandatory	Description
type	string	Yes	Listening type, which is set to ‘styleChange’ in this API.
callback	Callback<CaptionsStyle>	No	Callback used for disable listening. The value must be the same as the value of callback in on(‘styleChange’). If this parameter is not specified, listening will be disabled for all callbacks corresponding to the specified type.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';

let captionsManager = accessibility.getCaptionsManager();

captionsManager.off('styleChange', (data: accessibility.CaptionsStyle) => {
  console.info(`Unsubscribe caption manager style state change, result: ${JSON.stringify(data)}`);
});

EventInfo

Describes a GUI change event.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Properties

Name	Type	Mandatory	Description
type	EventType	Yes	Accessibility event type.
windowUpdateType	WindowUpdateType	No	Window update type.
bundleName	string	Yes	Name of the target application.
componentType	string	No	Type of the event source component, for example, button or chart.
pageId	number	No	Page ID of the event source.
description	string	No	Event description.
triggerAction	Action	Yes	Action that triggers the event.
textMoveUnit	TextMoveUnit	No	Text move granularity.
contents	Array<string>	No	Array of contents.
lastContent	string	No	Latest content.
beginIndex	number	No	Sequence number of the first item displayed on the page. Default value: 0.
currentIndex	number	No	Sequence number of the current item. Default value: 0.
endIndex	number	No	Sequence number of the last item displayed on the page. Default value: 0.
itemCount	number	No	Total number of records. Default value: 0.
elementId12+	number	No	Element ID of the component. Default value: 0.
textAnnouncedForAccessibility12+	string	No	Content for auto-broadcasting.
textResourceAnnouncedForAccessibility18+	Resource	No	Content for auto-broadcasting, which supports resources of the string type.
customId12+	string	No	Component ID for auto-focusing.

constructor

constructor(jsonObject)

Implements a constructor.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
jsonObject	string	Yes	JSON string required for creating an object.

Example

  import { accessibility } from '@kit.AccessibilityKit';

  let eventInfo: accessibility.EventInfo = ({
    type: 'click',
    bundleName: 'com.example.MyApplication',
    triggerAction: 'click',
  });

constructor¹¹⁺

constructor(type: EventType, bundleName: string, triggerAction: Action)

Implements a constructor.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
type	EventType	Yes	Accessibility event types.
bundleName	string	Yes	Target application name.
triggerAction	Action	Yes	Action that triggers the event.

Example

  import { accessibility } from '@kit.AccessibilityKit';

  let eventInfo = new accessibility.EventInfo('click', 'com.example.MyApplication', 'click');

EventType

type EventType = ‘accessibilityFocus’|‘accessibilityFocusClear’| ‘click’|‘longClick’|‘focus’|‘select’|‘hoverEnter’|‘hoverExit’| ‘textUpdate’|‘textSelectionUpdate’|‘scroll’|‘requestFocusForAccessibility’| ‘announceForAccessibility’|‘requestFocusForAccessibilityNotInterrupt’| ‘announceForAccessibilityNotInterrupt’|‘scrolling’

Enumerates accessibility event types.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Type	Description
‘accessibilityFocus’	Event indicating that the accessibility focus is obtained.
‘accessibilityFocusClear’	Event indicating that the accessibility focus is cleared.
‘click’	Event of clicking a component.
‘longClick’	Event indicating that the component is long pressed.
‘select’	Event of selecting a component.
‘hoverEnter’	Event indicating that the hover enters a component.
‘hoverExit’	Event indicating that the hover exits a component.
‘focus’	Event indicating that the component obtains the focus. Not supported currently.
‘textUpdate’	Event indicating that the component text has been updated.
‘textSelectionUpdate’	Event indicating that the selected text has been updated. Not supported currently.
‘scroll’	Event of the scroll view.
‘requestFocusForAccessibility’	Event of the auto-focusing.
‘announceForAccessibility’	Event of the auto-broadcasting.
‘requestFocusForAccessibilityNotInterrupt’	Event of the auto-focusing without interruption. This event is supported since API version 18.
‘announceForAccessibilityNotInterrupt’	Event of the auto-broadcasting without interruption. This event is supported since API version 18.
‘scrolling’	Event indicating that an item is scrolled out of the screen in the scrolling view. This event is supported since API version 18.

TextMoveUnit

type TextMoveUnit = ‘char’|‘word’|‘line’|‘page’|‘paragraph’

Enumerates the movement units for traversing the node text.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Type	Description
‘char’	The movement unit for traversing the node text is by character.
‘word’	The movement unit for traversing the node text is by word.
‘line’	The movement unit for traversing the node text is by line.
‘page’	The movement unit for traversing the node text is by page.
‘paragraph’	The movement unit for traversing the node text is by paragraph.

WindowUpdateType

type WindowUpdateType = ‘add’|‘remove’|‘bounds’|‘active’|‘focus’

Enumerates window update types.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Type	Description
‘add’	Window adding.
‘remove’	Window deletion.
‘bounds’	Window boundary change.
‘active’	Window activity change.
‘focus’	Window focus change.

accessibility.getAbilityLists^(deprecated)

getAbilityLists(abilityType: AbilityType, stateType: AbilityState): Promise<Array<AccessibilityAbilityInfo>>

Obtains the accessibility application list. This API uses a promise to return the result.

NOTE

This API is supported since API version 7 and deprecated since API version 9. You are advised to use accessibility.getAccessibilityExtensionList() instead.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
abilityType	AbilityType	Yes	Accessibility application type.
stateType	AbilityState	Yes	Accessibility application status.

Return value

Type	Description
Promise<Array<AccessibilityAbilityInfo>>	Promise used to return the accessibility application list.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let abilityType: accessibility.AbilityType = 'spoken';
let abilityState: accessibility.AbilityState = 'enable';

accessibility.getAbilityLists(abilityType, abilityState).then((data: accessibility.AccessibilityAbilityInfo[]) => {
  console.info(`Succeeded in get accessibility extension list, ${JSON.stringify(data)}`);
}).catch((err: BusinessError) => {
  console.error(`failed to get accessibility extension list because ${JSON.stringify(err)}`);
});

accessibility.getAbilityLists^(deprecated)

getAbilityLists(abilityType: AbilityType, stateType: AbilityState,callback: AsyncCallback<Array<AccessibilityAbilityInfo>>): void

Obtains the accessibility application list. This API uses an asynchronous callback to return the result.

NOTE

This API is supported since API version 7 and deprecated since API version 9. You are advised to use accessibility.getAccessibilityExtensionList() instead.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
abilityType	AbilityType	Yes	Accessibility application type.
stateType	AbilityState	Yes	Accessibility application status.
callback	AsyncCallback<Array<AccessibilityAbilityInfo>>	Yes	Callback used to return the accessibility application list.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let abilityType: accessibility.AbilityType = 'spoken';
let abilityState: accessibility.AbilityState = 'enable';

accessibility.getAbilityLists(abilityType, abilityState, (err: BusinessError, data: accessibility.AccessibilityAbilityInfo[]) => {
  if (err) {
    console.error(`failed to get accessibility extension list because ${JSON.stringify(err)}`);
    return;
  }
  console.info(`Succeeded in get accessibility extension list, ${JSON.stringify(data)}`);
})

accessibility.getAccessibilityExtensionList⁹⁺

getAccessibilityExtensionList(abilityType: AbilityType, stateType: AbilityState): Promise<Array<AccessibilityAbilityInfo>>

Obtains the accessibility application list. This API uses a promise to return the result.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
abilityType	AbilityType	Yes	Accessibility application type.
stateType	AbilityState	Yes	Accessibility application status.

Return value

Type	Description
Promise<Array<AccessibilityAbilityInfo>>	Promise used to return the accessibility application list.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let abilityType: accessibility.AbilityType = 'spoken';
let abilityState: accessibility.AbilityState = 'enable';

accessibility.getAccessibilityExtensionList(abilityType, abilityState).then((data: accessibility.AccessibilityAbilityInfo[]) => {
  console.info(`Succeeded in get accessibility extension list, ${JSON.stringify(data)}`);
}).catch((err: BusinessError) => {
  console.error(`failed to get accessibility extension list, Code is ${err.code}, message is ${err.message}`);
});

accessibility.getAccessibilityExtensionList⁹⁺

getAccessibilityExtensionList(abilityType: AbilityType, stateType: AbilityState, callback: AsyncCallback<Array<AccessibilityAbilityInfo>>): void

Obtains the accessibility application list. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
abilityType	AbilityType	Yes	Accessibility application type.
stateType	AbilityState	Yes	Accessibility application status.
callback	AsyncCallback<Array<AccessibilityAbilityInfo>>	Yes	Callback used to return the accessibility application list.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let abilityType: accessibility.AbilityType = 'spoken';
let abilityState: accessibility.AbilityState = 'enable';

accessibility.getAccessibilityExtensionList(abilityType, abilityState,(err: BusinessError, data: accessibility.AccessibilityAbilityInfo[]) => {
  if (err) {
    console.error(`failed to get accessibility extension list, Code is ${err.code}, message is ${err.message}`);
    return;
  }
  console.info(`Succeeded in get accessibility extension list, ${JSON.stringify(data)}`);
});

accessibility.getAccessibilityExtensionListSync¹²⁺

getAccessibilityExtensionListSync(abilityType: AbilityType, stateType: AbilityState): Array<AccessibilityAbilityInfo>

Obtains the API for synchronizing the accessibility application list.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
abilityType	AbilityType	Yes	Accessibility application type.
stateType	AbilityState	Yes	Accessibility application status.

Return value

Type	Description
Array<AccessibilityAbilityInfo>	Promise used to return the accessibility application list.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let abilityType: accessibility.AbilityType = 'all';
let abilityState: accessibility.AbilityState = 'install';
let data: accessibility.AccessibilityAbilityInfo[];

try {
  data = accessibility.getAccessibilityExtensionListSync(abilityType, abilityState);
  console.info(`Succeeded in get accessibility extension list, ${JSON.stringify(data)}`);
} catch (error) {
  let err = error as BusinessError;
  console.error(`error code: ${err.code}`);
}

accessibility.getCaptionsManager^(deprecated)

getCaptionsManager(): CaptionsManager

Obtains a CaptionsManager instance.

NOTE

This API is deprecated since API version 12. Related features are no longer available in the system.

System capability: SystemCapability.BarrierFree.Accessibility.Hearing

Return value

Type	Description
CaptionsManager	Captions configuration.

Example

import { accessibility } from '@kit.AccessibilityKit';

let captionsManager = accessibility.getCaptionsManager();

accessibility.on(‘accessibilityStateChange’)

on(type: ‘accessibilityStateChange’, callback: Callback<boolean>): void

Enables listening for the enabled status changes of the accessibility application. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
type	string	Yes	Listening type, which is set to ‘accessibilityStateChange’ in this API.
callback	Callback<boolean>	Yes	Callback invoked when the enabled status of accessibility application changes. The returned result indicates the global enabled status of the accessibility application.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';

accessibility.on('accessibilityStateChange', (data: boolean) => {
  console.info(`subscribe accessibility state change, result: ${JSON.stringify(data)}`);
});

accessibility.on(‘touchGuideStateChange’)

on(type: ‘touchGuideStateChange’, callback: Callback<boolean>): void

Enables listening for the enabled status changes of the touch guide mode. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.BarrierFree.Accessibility.Vision

Parameters

Name	Type	Mandatory	Description
type	string	Yes	Listening type, which is set to ‘touchGuideStateChange’ in this API.
callback	Callback<boolean>	Yes	Callback invoked when the enabled status of touch guide mode changes.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';

accessibility.on('touchGuideStateChange', (data: boolean) => {
  console.info(`subscribe touch guide state change, result: ${JSON.stringify(data)}`);
});

accessibility.on(‘screenReaderStateChange’)¹⁸⁺

on(type: ‘screenReaderStateChange’, callback: Callback<boolean>): void

Enables listening for the enabled status changes of the screen reader. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.BarrierFree.Accessibility.Vision

Parameters

Name	Type	Mandatory	Description
type	string	Yes	Listening type, which is set to ‘screenReaderStateChange’ in this API.
callback	Callback<boolean>	Yes	Callback invoked when the enabled status of screen reader changes.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';

accessibility.on('screenReaderStateChange', (data: boolean) => {
  console.info(`subscribe screen reader state change, result: ${JSON.stringify(data)}`);
});

accessibility.off(‘accessibilityStateChange’)

off(type: ‘accessibilityStateChange’, callback?: Callback<boolean>): void

Disables listening for the enabled status changes of the accessibility application. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
type	string	Yes	Listening type, which is set to ‘accessibilityStateChange’ in this API.
callback	Callback<boolean>	No	Callback used for disable listening. The value must be the same as the value of callback in accessibility.on(‘accessibilityStateChange’). If this parameter is not specified, listening will be disabled for all callbacks corresponding to the specified type.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';

accessibility.off('accessibilityStateChange', (data: boolean) => {
  console.info(`Unsubscribe accessibility state change, result: ${JSON.stringify(data)}`);
});

accessibility.off(‘touchGuideStateChange’)

off(type: ‘touchGuideStateChange’, callback?: Callback<boolean>): void

Disables listening for the enabled status changes of the touch guide mode. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
type	string	Yes	Listening type, which is set to ‘touchGuideStateChange’ in this API.
callback	Callback<boolean>	No	Callback used for disable listening. The value must be the same as the value of callback in accessibility.on(‘touchGuideStateChange’). If this parameter is not specified, listening will be disabled for all callbacks corresponding to the specified type.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';

accessibility.off('touchGuideStateChange', (data: boolean) => {
  console.info(`Unsubscribe touch guide state change, result: ${JSON.stringify(data)}`);
});

accessibility.off(‘screenReaderStateChange’)¹⁸⁺

off(type: ‘screenReaderStateChange’, callback?: Callback<boolean>): void

Disables listening for the enabled status changes of the screen reader. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
type	string	Yes	Listening type, which is set to ‘screenReaderStateChange’ in this API.
callback	Callback<boolean>	No	Callback used for disable listening. The value must be the same as the value of callback in accessibility.on(‘screenReaderStateChange’). If this parameter is not specified, listening will be disabled for all callbacks corresponding to the specified type.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';

accessibility.off('screenReaderStateChange', (data: boolean) => {
  console.info(`Unsubscribe screen reader state change, result: ${JSON.stringify(data)}`);
});

accessibility.isOpenAccessibility^(deprecated)

isOpenAccessibility(): Promise<boolean>

Checks whether accessibility is enabled. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 10.

You are advised to use accessibility.isOpenAccessibilitySync instead.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Return value

Type	Description
Promise<boolean>	Promise used to return the result. Returns true if accessibility is enabled; returns false otherwise.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

accessibility.isOpenAccessibility().then((data: boolean) => {
  console.info(`success data:isOpenAccessibility : ${JSON.stringify(data)}`)
}).catch((err: BusinessError) => {
  console.error(`failed to  isOpenAccessibility, Code is ${err.code}, message is ${err.message}`);
});

accessibility.isOpenAccessibility^(deprecated)

isOpenAccessibility(callback: AsyncCallback<boolean>): void

Checks whether accessibility is enabled. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 10.

You are advised to use accessibility.isOpenAccessibilitySync instead.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
callback	AsyncCallback<boolean>	Yes	Callback used to return the result. Returns true if accessibility is enabled; returns false otherwise.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

accessibility.isOpenAccessibility((err: BusinessError, data: boolean) => {
  if (err) {
    console.error(`failed to isOpenAccessibility, Code is ${err.code}, message is ${err.message}`);
    return;
  }
  console.info(`success data:isOpenAccessibility : ${JSON.stringify(data)}`);
});

accessibility.isOpenAccessibilitySync¹⁰⁺

isOpenAccessibilitySync(): boolean

Checks whether accessibility is enabled.

Atomic service API: This API can be used in atomic services since API version 11.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Return value

Type	Description
boolean	Returns true if accessibility is enabled; returns false otherwise.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let status: boolean = accessibility.isOpenAccessibilitySync();

accessibility.isOpenTouchGuide^(deprecated)

isOpenTouchGuide(): Promise<boolean>

Checks whether touch guide mode is enabled. This API uses a promise to return the result.

NOTE

This API is deprecated since API version 10.

You are advised to use accessibility.isOpenTouchGuideSync instead.

System capability: SystemCapability.BarrierFree.Accessibility.Vision

Return value

Type	Description
Promise<boolean>	Promise used to return the result. Returns true if touch guide mode is enabled; returns false otherwise.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

accessibility.isOpenTouchGuide().then((data: boolean) => {
  console.info(`success data:isOpenTouchGuide : ${JSON.stringify(data)}`);
}).catch((err: BusinessError) => {
  console.error(`failed to  isOpenTouchGuide, Code is ${err.code}, message is ${err.message}`);
});

accessibility.isOpenTouchGuide^(deprecated)

isOpenTouchGuide(callback: AsyncCallback<boolean>): void

Checks whether touch guide mode is enabled. This API uses an asynchronous callback to return the result.

NOTE

This API is deprecated since API version 10.

You are advised to use accessibility.isOpenTouchGuideSync instead.

System capability: SystemCapability.BarrierFree.Accessibility.Vision

Parameters

Name	Type	Mandatory	Description
callback	AsyncCallback<boolean>	Yes	Callback used to return the result. Returns true if touch guide mode is enabled; returns false otherwise.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

accessibility.isOpenTouchGuide((err: BusinessError, data: boolean) => {
  if (err) {
    console.error(`failed to isOpenTouchGuide, Code is ${err.code}, message is ${err.message}`);
    return;
  }
  console.info(`success data:isOpenTouchGuide : ${JSON.stringify(data)}`);
});

accessibility.isOpenTouchGuideSync¹⁰⁺

isOpenTouchGuideSync(): boolean

Checks whether touch guide mode is enabled.

Atomic service API: This API can be used in atomic services since API version 11.

System capability: SystemCapability.BarrierFree.Accessibility.Vision

Return value

Type	Description
boolean	Returns true if accessibility is enabled; returns false otherwise.

Example

import { accessibility } from '@kit.AccessibilityKit';

let status: boolean = accessibility.isOpenTouchGuideSync();

accessibility.isScreenReaderOpenSync¹⁸⁺

isScreenReaderOpenSync(): boolean

Checks whether the screen reader mode is enabled.

Atomic service API: This API can be used in atomic services since API version 18.

System capability: SystemCapability.BarrierFree.Accessibility.Vision

Return value

Type	Description
boolean	Returns true if screen reader is enabled; returns false otherwise.

Example

import { accessibility } from '@kit.AccessibilityKit';

let status: boolean = accessibility.isScreenReaderOpenSync();

accessibility.sendEvent^(deprecated)

sendEvent(event: EventInfo): Promise<void>

Sends an accessibility event. This API uses a promise to return the result.

NOTE

This API is supported since API version 7 and deprecated since API version 9. You are advised to use accessibility.sendAccessibilityEvent() instead.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
event	EventInfo	Yes	Accessibility event.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let eventInfo: accessibility.EventInfo = ({
  type: 'click',
  bundleName: 'com.example.MyApplication',
  triggerAction: 'click',
});

accessibility.sendEvent(eventInfo).then(() => {
  console.info(`Succeeded in send event,eventInfo is ${eventInfo}`);
}).catch((err: BusinessError) => {
  console.error(`failed to sendEvent, Code is ${err.code}, message is ${err.message}`);
});

accessibility.sendEvent^(deprecated)

sendEvent(event: EventInfo, callback: AsyncCallback<void>): void

Sends an accessibility event. This API uses an asynchronous callback to return the result.

NOTE

This API is supported since API version 7 and deprecated since API version 9. You are advised to use accessibility.sendAccessibilityEvent() instead.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
event	EventInfo	Yes	Accessibility event.
callback	AsyncCallback<void>	Yes	Callback used to return the result. If the operation fails, err that contains data is returned.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let eventInfo: accessibility.EventInfo = ({
  type: 'click',
  bundleName: 'com.example.MyApplication',
  triggerAction: 'click',
});

accessibility.sendEvent(eventInfo, (err: BusinessError) => {
  if (err) {
    console.error(`failed to sendEvent, Code is ${err.code}, message is ${err.message}`);
    return;
  }
  console.info(`Succeeded in sendEvent, eventInfo is ${eventInfo}`);
});

accessibility.sendAccessibilityEvent⁹⁺

sendAccessibilityEvent(event: EventInfo): Promise<void>

Sends an accessibility event. This API uses a promise to return the result.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
event	EventInfo	Yes	Accessibility event.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let eventInfo: accessibility.EventInfo = ({
  type: 'click',
  bundleName: 'com.example.MyApplication',
  triggerAction: 'click',
});

accessibility.sendAccessibilityEvent(eventInfo).then(() => {
  console.info(`Succeeded in send event,eventInfo is ${eventInfo}`);
}).catch((err: BusinessError) => {
  console.error(`failed to send event , Code is ${err.code}, message is ${err.message}`);
});

accessibility.sendAccessibilityEvent⁹⁺

sendAccessibilityEvent(event: EventInfo, callback: AsyncCallback<void>): void

Sends an accessibility event. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.BarrierFree.Accessibility.Core

Parameters

Name	Type	Mandatory	Description
event	EventInfo	Yes	Accessibility event.
callback	AsyncCallback<void>	Yes	Callback used to return the result. If the operation fails, err that contains data is returned.

Error codes

For details about the error codes, see Accessibility Error Codes.

ID	Error Message
401	Input parameter error. Possible causes: 1. Mandatory parameters are left unspecified; 2. Incorrect parameter types; 3. Parameter verification failed.

Example

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let eventInfo: accessibility.EventInfo = ({
  type: 'click',
  bundleName: 'com.example.MyApplication',
  triggerAction: 'click',
});

accessibility.sendAccessibilityEvent(eventInfo, (err: BusinessError) => {
  if (err) {
    console.error(`failed to send event, Code is ${err.code}, message is ${err.message}`);
    return;
  }
  console.info(`Succeeded in send event, eventInfo is ${eventInfo}`);
});

Example of auto-focusing:

@Entry
@Component
struct Index {

  build() {
    Column() {
      // Add the ID attribute to the component to be focused. The uniqueness of the ID is ensured by the user.
      Button ('Component to be focused').id ('click')
    }
  }
}

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let eventInfo: accessibility.EventInfo = ({
  type: 'requestFocusForAccessibility',
  bundleName: 'com.example.MyApplication',
  triggerAction: 'common',
  customId: 'click' // ID of the component to be focused.
});

accessibility.sendAccessibilityEvent(eventInfo, (err: BusinessError) => {
  if (err) {
    console.error(`failed to send event, Code is ${err.code}, message is ${err.message}`);
    return;
  }
  console.info(`Succeeded in send event, eventInfo is ${eventInfo}`);
});

Example of resource-supported auto-broadcasting¹⁸⁺:

import { accessibility } from '@kit.AccessibilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let eventInfo: accessibility.EventInfo = ({
  type: 'announceForAccessibility',
  bundleName: 'com.example.MyApplication',
  triggerAction: 'common',
  textResourceAnnouncedForAccessibility: $r('app.string.ResourceName'),
});

accessibility.sendAccessibilityEvent(eventInfo, (err: BusinessError) => {
  if (err) {
    console.error(`failed to send event, Code is ${err.code}, message is ${err.message}`);
    return;
  }
  console.info(`Succeeded in send event, eventInfo is ${eventInfo}`);
});

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