expo-sensors/src/LightSensor.ts

Provides access to a hardware device's accelerometer, gyroscope, magnetometer, and pedometer.

import DeviceSensor from './DeviceSensor';
import type { Listener, Subscription } from './DeviceSensor';
import ExpoLightSensor from './ExpoLightSensor';

export type LightSensorMeasurement = {
  /**
   * Ambient light level registered by the device measured in lux (lx).
   */
  illuminance: number;
  /**
   * Timestamp of the measurement in seconds.
   */
  timestamp: number;
};

/**
 * @platform android
 */
export class LightSensor extends DeviceSensor<LightSensorMeasurement> {
  /**
   * > **info** You should always check the sensor availability before attempting to use it.
   *
   * Returns whether the light sensor is available and enabled on the device. Requires at least Android 2.3 (API Level 9).
   *
   * @return A promise that resolves to a `boolean` denoting the availability of the light sensor.
   */
  async isAvailableAsync(): Promise<boolean> {
    return super.isAvailableAsync();
  }

  /**
   * Subscribe for updates to the light sensor.
   *
   * @param listener A callback that is invoked when a LightSensor update is available. When invoked,
   * the listener is provided a single argument that is the illuminance value.
   *
   * @return A subscription that you can call `remove()` on when you would like to unsubscribe the listener.
   */
  addListener(listener: Listener<LightSensorMeasurement>): Subscription {
    return super.addListener(listener);
  }
}

export default new LightSensor(ExpoLightSensor, 'lightSensorDidUpdate');