add support for Android's "High Text Contrast" setting into AccessibilityInfo (#46746)

Summary:
Pull Request resolved: #46746

This change adds `isHighTextContrastEnabled()` to `AccessibilityInfo` to enable access to Android OS's "High contrast text" setting option. It also adds a new event, `highContrastTextChanged`, to enable listeners to subscribe to changes on this setting.

## Changelog

[Android][Added] - Added `isHighTextContrastEnabled()` to `AccessibilityInfo` to read `ACCESSIBILITY_HIGH_TEXT_CONTRAST_ENABLED` setting value

Reviewed By: NickGerleman

Differential Revision: D63155444

fbshipit-source-id: 9829b40e6c183f6beba732190dc318894e9d9a3f

Author: Ariel Lin

packages/react-native/Libraries/Components/AccessibilityInfo/AccessibilityInfo.d.ts

@@ -17,6 +17,7 @@ type AccessibilityChangeEventName =
   | 'grayscaleChanged' // iOS-only Event
   | 'invertColorsChanged' // iOS-only Event
   | 'reduceMotionChanged'
+  | 'highTextContrastChanged' // Android-only Event
   | 'screenReaderChanged'
   | 'reduceTransparencyChanged'; // iOS-only Event
 
@@ -69,6 +70,14 @@ export interface AccessibilityInfoStatic {
    */
   isReduceMotionEnabled: () => Promise<boolean>;
 
+  /**
+   *
+   * Query whether high text contrast is currently enabled.
+   *
+   * @platform android
+   */
+  isHighTextContrastEnabled: () => Promise<boolean>;
+
   /**
    * Query whether reduce motion and prefer cross-fade transitions settings are currently enabled.
    *

packages/react-native/Libraries/Components/AccessibilityInfo/AccessibilityInfo.js

@@ -22,6 +22,7 @@ import NativeAccessibilityManagerIOS from './NativeAccessibilityManager';
 // Events that are only supported on Android.
 type AccessibilityEventDefinitionsAndroid = {
   accessibilityServiceChanged: [boolean],
+  highTextContrastChanged: [boolean],
 };
 
 // Events that are only supported on iOS.
@@ -51,6 +52,7 @@ const EventNames: Map<
   ? new Map([
       ['change', 'touchExplorationDidChange'],
       ['reduceMotionChanged', 'reduceMotionDidChange'],
+      ['highTextContrastChanged', 'highTextContrastDidChange'],
       ['screenReaderChanged', 'touchExplorationDidChange'],
       ['accessibilityServiceChanged', 'accessibilityServiceDidChange'],
     ])
@@ -179,6 +181,26 @@ const AccessibilityInfo = {
     });
   },
 
+  /**
+   * Query whether high text contrast is currently enabled. Android only.
+   *
+   * Returns a promise which resolves to a boolean.
+   * The result is `true` when high text contrast is enabled and `false` otherwise.
+   */
+  isHighTextContrastEnabled(): Promise<boolean> {
+    return new Promise((resolve, reject) => {
+      if (Platform.OS === 'android') {
+        if (NativeAccessibilityInfoAndroid?.isHighTextContrastEnabled != null) {
+          NativeAccessibilityInfoAndroid.isHighTextContrastEnabled(resolve);
+        } else {
+          reject(null);
+        }
+      } else {
+        return Promise.resolve(false);
+      }
+    });
+  },
+
   /**
    * Query whether reduce motion and prefer cross-fade transitions settings are currently enabled.
    *
@@ -320,6 +342,12 @@ const AccessibilityInfo = {
    *     - `success`: A boolean indicating whether the announcement was
    *       successfully made.
    *
+   * These events are only supported on Android:
+   *
+   * - `highTextContrastChanged`: Android-only event. Fires when the state of the high text contrast
+   *   toggle changes. The argument to the event handler is a boolean. The boolean is `true` when
+   *   high text contrast is enabled and `false` otherwise.
+   *
    * See https://reactnative.dev/docs/accessibilityinfo#addeventlistener
    */
   addEventListener<K: $Keys<AccessibilityEventDefinitions>>(

packages/react-native/Libraries/__tests__/__snapshots__/public-api-test.js.snap

@@ -1559,6 +1559,7 @@ declare module.exports: getData;
 exports[`public API should not change unintentionally Libraries/Components/AccessibilityInfo/AccessibilityInfo.js 1`] = `
 "type AccessibilityEventDefinitionsAndroid = {
   accessibilityServiceChanged: [boolean],
+  highTextContrastChanged: [boolean],
 };
 type AccessibilityEventDefinitionsIOS = {
   announcementFinished: [{ announcement: string, success: boolean }],
@@ -1580,6 +1581,7 @@ declare const AccessibilityInfo: {
   isGrayscaleEnabled(): Promise<boolean>,
   isInvertColorsEnabled(): Promise<boolean>,
   isReduceMotionEnabled(): Promise<boolean>,
+  isHighTextContrastEnabled(): Promise<boolean>,
   prefersCrossFadeTransitions(): Promise<boolean>,
   isReduceTransparencyEnabled(): Promise<boolean>,
   isScreenReaderEnabled(): Promise<boolean>,

packages/react-native/ReactAndroid/api/ReactAndroid.api

@@ -3021,6 +3021,7 @@ public final class com/facebook/react/modules/accessibilityinfo/AccessibilityInf
 	public fun initialize ()V
 	public fun invalidate ()V
 	public fun isAccessibilityServiceEnabled (Lcom/facebook/react/bridge/Callback;)V
+	public fun isHighTextContrastEnabled (Lcom/facebook/react/bridge/Callback;)V
 	public fun isReduceMotionEnabled (Lcom/facebook/react/bridge/Callback;)V
 	public fun isTouchExplorationEnabled (Lcom/facebook/react/bridge/Callback;)V
 	public fun onHostDestroy ()V

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/modules/accessibilityinfo/AccessibilityInfoModule.kt

@@ -62,13 +62,27 @@ public class AccessibilityInfoModule(context: ReactApplicationContext) :
           }
         }
       }
+  // Listener that is notified when the ACCESSIBILITY_HIGH_TEXT_CONTRAST_ENABLED changes.
+  private val highTextContrastObserver: ContentObserver =
+      object : ContentObserver(UiThreadUtil.getUiThreadHandler()) {
+        override fun onChange(selfChange: Boolean) {
+          this.onChange(selfChange, null)
+        }
+
+        override fun onChange(selfChange: Boolean, uri: Uri?) {
+          if (getReactApplicationContext().hasActiveReactInstance()) {
+            updateAndSendHighTextContrastChangeEvent()
+          }
+        }
+      }
   private val accessibilityManager: AccessibilityManager?
   private val touchExplorationStateChangeListener: ReactTouchExplorationStateChangeListener =
       ReactTouchExplorationStateChangeListener()
   private val accessibilityServiceChangeListener: ReactAccessibilityServiceChangeListener =
       ReactAccessibilityServiceChangeListener()
   private val contentResolver: ContentResolver
   private var reduceMotionEnabled = false
+  private var highTextContrastEnabled = false
   private var touchExplorationEnabled = false
   private var accessibilityServiceEnabled = false
   private var recommendedTimeout = 0
@@ -81,6 +95,7 @@ public class AccessibilityInfoModule(context: ReactApplicationContext) :
     touchExplorationEnabled = accessibilityManager.isTouchExplorationEnabled
     accessibilityServiceEnabled = accessibilityManager.isEnabled
     reduceMotionEnabled = isReduceMotionEnabledValue
+    highTextContrastEnabled = isHighTextContrastEnabledValue
   }
 
   @get:TargetApi(Build.VERSION_CODES.LOLLIPOP)
@@ -96,10 +111,24 @@ public class AccessibilityInfoModule(context: ReactApplicationContext) :
       return parsedValue == 0f
     }
 
+  @get:TargetApi(Build.VERSION_CODES.LOLLIPOP)
+  private val isHighTextContrastEnabledValue: Boolean
+    get() {
+      return Settings.Secure.getInt(
+          contentResolver,
+          ACCESSIBILITY_HIGH_TEXT_CONTRAST_ENABLED_CONSTANT,
+          0,
+      ) != 0
+    }
+
   override fun isReduceMotionEnabled(successCallback: Callback) {
     successCallback.invoke(reduceMotionEnabled)
   }
 
+  override fun isHighTextContrastEnabled(successCallback: Callback) {
+    successCallback.invoke(highTextContrastEnabled)
+  }
+
   override fun isTouchExplorationEnabled(successCallback: Callback) {
     successCallback.invoke(touchExplorationEnabled)
   }
@@ -119,6 +148,20 @@ public class AccessibilityInfoModule(context: ReactApplicationContext) :
     }
   }
 
+  private fun updateAndSendHighTextContrastChangeEvent() {
+    val isHighTextContrastEnabled = isHighTextContrastEnabledValue
+    if (highTextContrastEnabled != isHighTextContrastEnabled) {
+      highTextContrastEnabled = isHighTextContrastEnabled
+      val reactApplicationContext = getReactApplicationContextIfActiveOrWarn()
+      if (reactApplicationContext != null) {
+        reactApplicationContext.emitDeviceEvent(
+            HIGH_TEXT_CONTRAST_EVENT_NAME,
+            highTextContrastEnabled,
+        )
+      }
+    }
+  }
+
   private fun updateAndSendTouchExplorationChangeEvent(enabled: Boolean) {
     if (touchExplorationEnabled != enabled) {
       touchExplorationEnabled = enabled
@@ -148,10 +191,14 @@ public class AccessibilityInfoModule(context: ReactApplicationContext) :
     accessibilityManager?.addAccessibilityStateChangeListener(accessibilityServiceChangeListener)
     val transitionUri = Settings.Global.getUriFor(Settings.Global.TRANSITION_ANIMATION_SCALE)
     contentResolver.registerContentObserver(transitionUri, false, animationScaleObserver)
+    val highTextContrastUri =
+        Settings.Global.getUriFor(ACCESSIBILITY_HIGH_TEXT_CONTRAST_ENABLED_CONSTANT)
+    contentResolver.registerContentObserver(highTextContrastUri, false, highTextContrastObserver)
     updateAndSendTouchExplorationChangeEvent(
         accessibilityManager?.isTouchExplorationEnabled == true)
     updateAndSendAccessibilityServiceChangeEvent(accessibilityManager?.isEnabled == true)
     updateAndSendReduceMotionChangeEvent()
+    updateAndSendHighTextContrastChangeEvent()
   }
 
   @TargetApi(Build.VERSION_CODES.LOLLIPOP)
@@ -160,6 +207,7 @@ public class AccessibilityInfoModule(context: ReactApplicationContext) :
         touchExplorationStateChangeListener)
     accessibilityManager?.removeAccessibilityStateChangeListener(accessibilityServiceChangeListener)
     contentResolver.unregisterContentObserver(animationScaleObserver)
+    contentResolver.unregisterContentObserver(highTextContrastObserver)
   }
 
   override fun initialize() {
@@ -168,6 +216,7 @@ public class AccessibilityInfoModule(context: ReactApplicationContext) :
         accessibilityManager?.isTouchExplorationEnabled == true)
     updateAndSendAccessibilityServiceChangeEvent(accessibilityManager?.isEnabled == true)
     updateAndSendReduceMotionChangeEvent()
+    updateAndSendHighTextContrastChangeEvent()
   }
 
   override fun invalidate() {
@@ -200,13 +249,18 @@ public class AccessibilityInfoModule(context: ReactApplicationContext) :
     }
     recommendedTimeout =
         accessibilityManager?.getRecommendedTimeoutMillis(
-            originalTimeout.toInt(), AccessibilityManager.FLAG_CONTENT_CONTROLS) ?: 0
+            originalTimeout.toInt(),
+            AccessibilityManager.FLAG_CONTENT_CONTROLS,
+        ) ?: 0
     successCallback.invoke(recommendedTimeout)
   }
 
   private companion object {
     private const val REDUCE_MOTION_EVENT_NAME = "reduceMotionDidChange"
+    private const val HIGH_TEXT_CONTRAST_EVENT_NAME = "highTextContrastDidChange"
     private const val TOUCH_EXPLORATION_EVENT_NAME = "touchExplorationDidChange"
     private const val ACCESSIBILITY_SERVICE_EVENT_NAME = "accessibilityServiceDidChange"
+    private const val ACCESSIBILITY_HIGH_TEXT_CONTRAST_ENABLED_CONSTANT =
+        "high_text_contrast_enabled" // constant is marked with @hide
   }
 }

packages/react-native/jest/setup.js

@@ -151,6 +151,7 @@ jest
       isGrayscaleEnabled: jest.fn(() => Promise.resolve(false)),
       isInvertColorsEnabled: jest.fn(() => Promise.resolve(false)),
       isReduceMotionEnabled: jest.fn(() => Promise.resolve(false)),
+      isHighTextContrastEnabled: jest.fn(() => Promise.resolve(false)),
       prefersCrossFadeTransitions: jest.fn(() => Promise.resolve(false)),
       isReduceTransparencyEnabled: jest.fn(() => Promise.resolve(false)),
       isScreenReaderEnabled: jest.fn(() => Promise.resolve(false)),

packages/react-native/src/private/specs/modules/NativeAccessibilityInfo.js

@@ -16,6 +16,9 @@ export interface Spec extends TurboModule {
   +isReduceMotionEnabled: (
     onSuccess: (isReduceMotionEnabled: boolean) => void,
   ) => void;
+  +isHighTextContrastEnabled?: (
+    onSuccess: (isHighTextContrastEnabled: boolean) => void,
+  ) => void;
   +isTouchExplorationEnabled: (
     onSuccess: (isScreenReaderEnabled: boolean) => void,
   ) => void;