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AccessibilityInfo

website/versioned_docs/version-0.78/accessibilityinfo.md

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Sometimes it's useful to know whether or not the device has a screen reader that is currently active. The AccessibilityInfo API is designed for this purpose. You can use it to query the current state of the screen reader as well as to register to be notified when the state of the screen reader changes.

Example

SnackPlayer
import React, {useState, useEffect} from 'react';
import {AccessibilityInfo, Text, StyleSheet} from 'react-native';
import {SafeAreaView, SafeAreaProvider} from 'react-native-safe-area-context';

const App = () => {
  const [reduceMotionEnabled, setReduceMotionEnabled] = useState(false);
  const [screenReaderEnabled, setScreenReaderEnabled] = useState(false);

  useEffect(() => {
    const reduceMotionChangedSubscription = AccessibilityInfo.addEventListener(
      'reduceMotionChanged',
      isReduceMotionEnabled => {
        setReduceMotionEnabled(isReduceMotionEnabled);
      },
    );
    const screenReaderChangedSubscription = AccessibilityInfo.addEventListener(
      'screenReaderChanged',
      isScreenReaderEnabled => {
        setScreenReaderEnabled(isScreenReaderEnabled);
      },
    );

    AccessibilityInfo.isReduceMotionEnabled().then(isReduceMotionEnabled => {
      setReduceMotionEnabled(isReduceMotionEnabled);
    });
    AccessibilityInfo.isScreenReaderEnabled().then(isScreenReaderEnabled => {
      setScreenReaderEnabled(isScreenReaderEnabled);
    });

    return () => {
      reduceMotionChangedSubscription.remove();
      screenReaderChangedSubscription.remove();
    };
  }, []);

  return (
    <SafeAreaProvider>
      <SafeAreaView style={styles.container}>
        <Text style={styles.status}>
          The reduce motion is {reduceMotionEnabled ? 'enabled' : 'disabled'}.
        </Text>
        <Text style={styles.status}>
          The screen reader is {screenReaderEnabled ? 'enabled' : 'disabled'}.
        </Text>
      </SafeAreaView>
    </SafeAreaProvider>
  );
};

const styles = StyleSheet.create({
  container: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'center',
  },
  status: {
    margin: 30,
  },
});

export default App;

Reference

Methods

addEventListener()

tsx
static addEventListener(
  eventName: AccessibilityChangeEventName | AccessibilityAnnouncementEventName,
  handler: (
    event: AccessibilityChangeEvent | AccessibilityAnnouncementFinishedEvent,
  ) => void,
): EmitterSubscription;

Add an event handler. Supported events:

Event nameDescription
accessibilityServiceChanged
<div className="label two-lines android">Android</div> | Fires when some services such as TalkBack, other Android assistive technologies, and third-party accessibility services are enabled. The argument to the event handler is a boolean. The boolean is `true` when a some accessibility services is enabled and `false` otherwise. | | `announcementFinished` <div className="label two-lines ios">iOS</div> | Fires when the screen reader has finished making an announcement. The argument to the event handler is a dictionary with these keys:<ul><li>`announcement`: The string announced by the screen reader.</li><li>`success`: A boolean indicating whether the announcement was successfully made.</li></ul> | | `boldTextChanged` <div className="label two-lines ios">iOS</div> | Fires when the state of the bold text toggle changes. The argument to the event handler is a boolean. The boolean is `true` when bold text is enabled and `false` otherwise. | | `grayscaleChanged` <div className="label two-lines ios">iOS</div> | Fires when the state of the gray scale toggle changes. The argument to the event handler is a boolean. The boolean is `true` when a gray scale is enabled and `false` otherwise. | | `invertColorsChanged` <div className="label two-lines ios">iOS</div> | Fires when the state of the invert colors toggle changes. The argument to the event handler is a boolean. The boolean is `true` when invert colors is enabled and `false` otherwise. | | `reduceMotionChanged` | Fires when the state of the reduce motion toggle changes. The argument to the event handler is a boolean. The boolean is `true` when a reduce motion is enabled (or when "Transition Animation Scale" in "Developer options" is "Animation off") and `false` otherwise. | | `reduceTransparencyChanged` <div className="label two-lines ios">iOS</div> | Fires when the state of the reduce transparency toggle changes. The argument to the event handler is a boolean. The boolean is `true` when reduce transparency is enabled and `false` otherwise. | | `screenReaderChanged` | Fires when the state of the screen reader changes. The argument to the event handler is a boolean. The boolean is `true` when a screen reader is enabled and `false` otherwise. |

announceForAccessibility()

tsx
static announceForAccessibility(announcement: string);

Post a string to be announced by the screen reader.


announceForAccessibilityWithOptions()

tsx
static announceForAccessibilityWithOptions(
  announcement: string,
  options: {queue?: boolean},
);

Post a string to be announced by the screen reader with modification options. By default announcements will interrupt any existing speech, but on iOS they can be queued behind existing speech by setting queue to true in the options object.

Parameters:

NameTypeDescription
announcement <div className="label basic required">Required</div>stringThe string to be announced
options <div className="label basic required">Required</div>objectqueue - queue the announcement behind existing speech <div className="label ios">iOS</div>

getRecommendedTimeoutMillis() <div className="label android">Android</div>

tsx
static getRecommendedTimeoutMillis(originalTimeout: number): Promise<number>;

Gets the timeout in millisecond that the user needs. This value is set in "Time to take action (Accessibility timeout)" of "Accessibility" settings.

Parameters:

NameTypeDescription
originalTimeout <div className="label basic required">Required</div>numberThe timeout to return if "Accessibility timeout" is not set. Specify in milliseconds.

isAccessibilityServiceEnabled() <div className="label android">Android</div>

tsx
static isAccessibilityServiceEnabled(): Promise<boolean>;

Check whether any accessibility service is enabled. This includes TalkBack but also any third-party accessibility app that may be installed. To only check whether TalkBack is enabled, use isScreenReaderEnabled. Returns a promise which resolves to a boolean. The result is true when some accessibility services is enabled and false otherwise.

Note: Please use isScreenReaderEnabled if you only want to check the status of TalkBack.


isBoldTextEnabled() <div className="label ios">iOS</div>

tsx
static isBoldTextEnabled(): Promise<boolean>:

Query whether a bold text is currently enabled. Returns a promise which resolves to a boolean. The result is true when bold text is enabled and false otherwise.


isGrayscaleEnabled() <div className="label ios">iOS</div>

tsx
static isGrayscaleEnabled(): Promise<boolean>;

Query whether grayscale is currently enabled. Returns a promise which resolves to a boolean. The result is true when grayscale is enabled and false otherwise.


isInvertColorsEnabled() <div className="label ios">iOS</div>

tsx
static isInvertColorsEnabled(): Promise<boolean>;

Query whether invert colors is currently enabled. Returns a promise which resolves to a boolean. The result is true when invert colors is enabled and false otherwise.


isReduceMotionEnabled()

tsx
static isReduceMotionEnabled(): Promise<boolean>;

Query whether reduce motion is currently enabled. Returns a promise which resolves to a boolean. The result is true when reduce motion is enabled and false otherwise.


isReduceTransparencyEnabled() <div className="label ios">iOS</div>

tsx
static isReduceTransparencyEnabled(): Promise<boolean>;

Query whether reduce transparency is currently enabled. Returns a promise which resolves to a boolean. The result is true when a reduce transparency is enabled and false otherwise.


isScreenReaderEnabled()

tsx
static isScreenReaderEnabled(): Promise<boolean>;

Query whether a screen reader is currently enabled. Returns a promise which resolves to a boolean. The result is true when a screen reader is enabled and false otherwise.


isHighTextContrastEnabled() <div className="label android">Android</div>

tsx
static isHighTextContrastEnabled(): Promise<boolean>

Query whether high text contrast is currently enabled. Returns a promise which resolves to a boolean. The result is true when high text contrast is enabled and false otherwise.


isDarkerSystemColorsEnabled() <div className="label ios">iOS</div>

tsx
static isDarkerSystemColorsEnabled(): Promise<boolean>

Query whether dark system colors is currently enabled. Returns a promise which resolves to a boolean. The result is true when dark system colors is enabled and false otherwise.


prefersCrossFadeTransitions() <div className="label ios">iOS</div>

tsx
static prefersCrossFadeTransitions(): Promise<boolean>;

Query whether reduce motion and prefer cross-fade transitions settings are currently enabled. Returns a promise which resolves to a boolean. The result is true when prefer cross-fade transitions is enabled and false otherwise.


setAccessibilityFocus()

:::warning Deprecated Prefer using sendAccessibilityEvent with eventType focus instead. :::

tsx
static setAccessibilityFocus(reactTag: number);

Set accessibility focus to a React component.

On Android, this calls UIManager.sendAccessibilityEvent method with passed reactTag and UIManager.AccessibilityEventTypes.typeViewFocused arguments.

:::note Make sure that any View you want to receive the accessibility focus has accessible={true}. :::


sendAccessibilityEvent()

tsx
static sendAccessibilityEvent(host: HostInstance, eventType: AccessibilityEventTypes);

Imperatively trigger an accessibility event on a React component, like changing the focused element for a screen reader.

:::note Make sure that any View you want to receive the accessibility focus has accessible={true}. :::

NameTypeDescription
host <div className="label basic required">Required</div>HostInstanceThe component ref to send the event to.
eventType <div className="label basic required">Required</div>AccessibilityEventTypesOne of 'click' (Android only), 'focus', 'viewHoverEnter' (Android only), or 'windowStateChange' (Android only)