Accessibility Framework Subsystem Changelog

cl.accessibility.1 Access Permission Change in the Listener APIs

Since API version 11, the ohos.permission.READ_ACCESSIBILITY_CONFIG permission verification is added to the listener APIs, and error code 201 is returned for lack of permission. This is a compatible change. You need to declare the required permission for your application to pass the verification.

Access Level

System

Reason for Change

In previous versions, the accessibility application could use the listener APIs without the ohos.permission.READ_ACCESSIBILITY_CONFIG permission. This is not secure and needs to be rectified.

Change Impact

This change is a compatible change and involves a new error code. An accessibility application must declare the ohos.permission.READ_ACCESSIBILITY_CONFIG permission to pass the permission verification.

Change Since

OpenHarmony SDK 4.1.5.2

Key API/Component Changes

The ohos.permission.READ_ACCESSIBILITY_CONFIG permission verification is added to the following APIs. Error code 201 is returned for lack of permission.

• Involved APIs

• Before change:

An accessibility application is not checked for its ohos.permission.READ_ACCESSIBILITY_CONFIG permission when it calls a listener API.

 /**
   * Register the listener that watches for changes in the enabled status of accessibility extensions.
   *
   * @param { 'enabledAccessibilityExtensionListChange' } type Indicates the type of event.
   * @param { Callback<void> } callback Indicates the listener.
   * @throws { BusinessError } 202 - Not system App.
   * @throws { BusinessError } 401 - Input parameter error.
   * @syscap SystemCapability.BarrierFree.Accessibility.Core
   * @systemapi
   * @since 9
   */
  function on(type: 'enabledAccessibilityExtensionListChange', callback: Callback<void>): void;
  
 /**
   * Unregister listener that watches for changes in the enabled status of accessibility extensions.
   *
   * @param { 'enabledAccessibilityExtensionListChange' } type Indicates the type of event.
   * @param { Callback<void> } callback Indicates the listener.
   * @throws { BusinessError } 202 - Not system App.
   * @throws { BusinessError } 401 - Input parameter error.
   * @syscap SystemCapability.BarrierFree.Accessibility.Core
   * @systemapi
   * @since 9
   */
  function off(type: 'enabledAccessibilityExtensionListChange', callback?: Callback<void>): void;

 /**
   * Register the listener to listen for configuration changes.
   *
   * @param { Callback<T> } callback Indicates the listener.
   * @throws { BusinessError } 201 - Permission denied.
   * @throws { BusinessError } 202 - Not system App.
   * @throws { BusinessError } 401 - Input parameter error.
   * @syscap SystemCapability.BarrierFree.Accessibility.Core
   * @systemapi
   * @since 9
   */
  on(callback: Callback<T>): void;
 
 /**
   * Unregister the listener to listen for configuration changes.
   *
   * @param { Callback<T> } callback Indicates the listener.
   * @throws { BusinessError } 202 - Not system App.
   * @syscap SystemCapability.BarrierFree.Accessibility.Core
   * @systemapi
   * @since 9
   */
  off(callback?: Callback<T>): void;

• After change:

An accessibility application is checked for its ohos.permission.READ_ACCESSIBILITY_CONFIG permission when it calls a listener API. Error code 201 is returned for lack of permission.

   /**
   * Register the listener that watches for changes in the enabled status of accessibility extensions.
   *
   * @permission ohos.permission.READ_ACCESSIBILITY_CONFIG
   * @param { 'enabledAccessibilityExtensionListChange' } type Indicates the type of event.
   * @param { Callback<void> } callback Indicates the listener.
   * @throws { BusinessError } 202 - Not system App.
   * @throws { BusinessError } 401 - Input parameter error.
   * @syscap SystemCapability.BarrierFree.Accessibility.Core
   * @systemapi
   * @since 9
   */
  function on(type: 'enabledAccessibilityExtensionListChange', callback: Callback<void>): void;
  
 /**
   * Unregister listener that watches for changes in the enabled status of accessibility extensions.
   *
   * @permission ohos.permission.READ_ACCESSIBILITY_CONFIG
   * @param { 'enabledAccessibilityExtensionListChange' } type Indicates the type of event.
   * @param { Callback<void> } callback Indicates the listener.
   * @throws { BusinessError } 202 - Not system App.
   * @throws { BusinessError } 401 - Input parameter error.
   * @syscap SystemCapability.BarrierFree.Accessibility.Core
   * @systemapi
   * @since 9
   */
  function off(type: 'enabledAccessibilityExtensionListChange', callback?: Callback<void>): void;

 /**
   * Register the listener to listen for configuration changes.
   *
   * @permission ohos.permission.READ_ACCESSIBILITY_CONFIG
   * @param { Callback<T> } callback Indicates the listener.
   * @throws { BusinessError } 201 - Permission denied.
   * @throws { BusinessError } 202 - Not system App.
   * @throws { BusinessError } 401 - Input parameter error.
   * @syscap SystemCapability.BarrierFree.Accessibility.Core
   * @systemapi
   * @since 9
   */
  on(callback: Callback<T>): void;
 
 /**
   * Unregister the listener to listen for configuration changes.
   *
   * @permission ohos.permission.READ_ACCESSIBILITY_CONFIG
   * @param { Callback<T> } callback Indicates the listener.
   * @throws { BusinessError } 202 - Not system App.
   * @syscap SystemCapability.BarrierFree.Accessibility.Core
   * @systemapi
   * @since 9
   */
  off(callback?: Callback<T>): void;

Adaptation Guide

Declare the required permission for calling a listener API.