Expo TaskManager example with EventEmitter

withEventEmitter.js

import React from 'react';
import { TaskManager } from 'expo';
import { EventEmitter } from 'fbemitter';

const taskName = 'task-name-of-your-choice';
const taskEventName = 'task-update';
const eventEmitter = new EventEmitter();

TaskManager.defineTask(taskName, ({ data, error }) => {
  if (!error) {
    // ... do something with given data (e.g. save to the storage) to keep data captured in the background
    
    eventEmitter.emit(taskEventName, data);
  }
});

export default class MyComponent extends React.Component {
  state = {
    taskData: null,
  };

  componentDidMount() {
    // ... restore data captured in the background
    
    this.eventSubscription = eventEmitter.addListener(taskEventName, data => {
      this.setState({ taskData: data });
    });
  }
  componentWillUnmount() {
    this.eventSubscription.remove();
  }

  // ... render stuff
}