index.android.js

// @flow

import { AppRegistry, NativeModules } from 'react-native'
import type { BackgroundTaskInterface } from './types'

const { AppState, BackgroundJob: RNBackgroundJob } = NativeModules
const JOB_KEY = 'backgroundTask'

const BackgroundTask: BackgroundTaskInterface = {

  register: function(task, {
    period = 9000000, // every 15 minutes
    timeout = 30,
  } = {}) {
    // Cancel any existing tasks, as we can only have one to match iOS, and we
    // have no way to tell whether the function has changed or not.
    RNBackgroundJob.cancelAll()

    // Register the headless task
    const fn = async () => { task() }
    AppRegistry.registerHeadlessTask(JOB_KEY, () => fn)

    // Schedule it to run as a periodic task
    AppState.getCurrentAppState(
      ({ appState }) => {
        RNBackgroundJob.schedule(
          JOB_KEY,
          timeout,
          period,
          true, // persist after restart
          RNBackgroundJob.ANY, // network type
          false, // requires charging
          false, // requires device idle
          appState === 'active',//false, // alwaysRunning,
          '',    // notificationTitle,
          '',    // notificationIcon,
          ''    // notificationText
        )
      },
      () => { console.error(`Can't get AppState`) }
    )
  },

  cancel: function() {
    RNBackgroundJob.cancelAll()
  },

  finish: function() {
    // Needed for iOS, no-op on Android
  },
}

module.exports = BackgroundTask