AccessibilityInfo

AccessibilityInfo

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.

Here's a small example illustrating how to use AccessibilityInfo:

class ScreenReaderStatusExample extends React.Component {
  state = {
    screenReaderEnabled: false,
  }

  componentDidMount() {
    AccessibilityInfo.addEventListener(
      'change',
      this._handleScreenReaderToggled
    );
    AccessibilityInfo.fetch().done((isEnabled) => {
      this.setState({
        screenReaderEnabled: isEnabled
      });
    });
  }

  componentWillUnmount() {
    AccessibilityInfo.removeEventListener(
      'change',
      this._handleScreenReaderToggled
    );
  }

  _handleScreenReaderToggled = (isEnabled) => {
    this.setState({
      screenReaderEnabled: isEnabled,
    });
  }

  render() {
    return (
      <View>
        <Text>
          The screen reader is {this.state.screenReaderEnabled ? 'enabled' : 'disabled'}.
        </Text>
      </View>
    );
  }
}

Methods

static fetch()

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.

static addEventListener(eventName, handler)

Add an event handler. Supported events:

  • change: 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.

static removeEventListener(eventName, handler)

Remove an event handler.

© 2015–2017 Facebook Inc.
Licensed under the Creative Commons Attribution 4.0 International Public License.
https://facebook.github.io/react-native/docs/accessibilityinfo.html

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