react-native-android-background-timer/index.js

Emit event periodically (even when app is in the background or the phone is locked)

import { NativeModules, DeviceEventEmitter } from 'react-native';

const NativeEVOBackgroundTimer = NativeModules.RNAndroidBackgroundTimerModule;

const listeners = {};
let uniqueId = 0;

const nextId = () => uniqueId++;

const RNAndroidBackgroundTimer = {
  setInterval(callback, delay){

    let id = nextId();
    listeners[id] = {
      isInterval: true,
      callback,
      timeout: delay,
    };

    NativeEVOBackgroundTimer.setTimeout(id, delay);
    return id;
  },
  clearInterval(id){
    listeners[id] && delete listeners[id];
  }
};

DeviceEventEmitter.addListener("rewieer.backgroundTimer.timeout", (id) => {
  const listener = listeners[id];
  if(!listener){
    return;
  }

  listener.callback();
  if(listener.isInterval){
    NativeEVOBackgroundTimer.setTimeout(id, listener.timeout);
    return;
  }

  delete listeners[id];
});

export default RNAndroidBackgroundTimer;