I need to frequently write into a text file, let's say write a timestamp into a file with react-native in iOS and android. I wrote an app by the help of the following libraries. On android, the app is working perfectly fine, but on iOS not working properly.
I tried to use these libraries:
- react-native-background-task
- react-native-background-fetch
- react-native-background-queue + react-native-background-task
But none of them works fine:
- with react-native-background-task: the file is written randomly 5-6times a day or less
- with react-native-background-fetch: the file is written randomly 3-4 times a day or less
- react-native-background-queue + react-native-background-task: thefile is not written AT ALL!
Would you please tell me if these behaviors are normal, and if not, what am I doing wrong???
Any help would be greatly appreciated.
Here are my codes:
In order to use react-native-background-task:
import React from 'react'import Mytest from './test';import BackgroundTask from 'react-native-background-task'import { Text, View, } from 'react-native';BackgroundTask.define(() => { console.log('Hello from a background task') Mytest.writeFiles() BackgroundTask.finish()})export default class MyApp extends React.Component { componentDidMount() { BackgroundTask.schedule() } render() { return(<View><Text>Hello world</Text></View>) }}
In order to use react-native-background-fetch:
import React, { Component } from 'react';import { Text, View, StyleSheet } from 'react-native';import BackgroundFetch from "react-native-background-fetch";var RNFS = require('react-native-fs');var path = RNFS.DocumentDirectoryPath +'/fetch.txt';var count = 0export default class App extends Component { constructor(props) { super(props); this.state = { date: '', } } componentDidMount() { BackgroundFetch.configure({ stopOnTerminate: false, startOnBoot: true, requiredNetworkType: BackgroundFetch.NETWORK_TYPE_NONE, requiresCharging: false, // Default requiresDeviceIdle: false, // Default requiresBatteryNotLow: false, // Default requiresStorageNotLow: false // Default }, () => { console.log("[js] Received background-fetch event"); this.writeFiles() BackgroundFetch.finish(BackgroundFetch.FETCH_RESULT_NEW_DATA); }, (error) => { console.log("[js] RNBackgroundFetch failed to start"); }); BackgroundFetch.status((status) => { switch(status) { case BackgroundFetch.STATUS_RESTRICTED: console.log("BackgroundFetch restricted"); break; case BackgroundFetch.STATUS_DENIED: console.log("BackgroundFetch denied"); break; case BackgroundFetch.STATUS_AVAILABLE: console.log("BackgroundFetch is enabled"); break; } }); } render() { return (<View style={styles.container}><Text style={styles.welcome}> Welcome to React Native!</Text></View> ); } getDate() { var that = this; var date = new Date().getDate(); //Current Date var month = new Date().getMonth() + 1; //Current Month var year = new Date().getFullYear(); //Current Year var hours = new Date().getHours(); //Current Hours var min = new Date().getMinutes(); //Current Minutes var sec = new Date().getSeconds(); //Current Seconds that.setState({ date: date +'/'+ month +'/'+ year +''+ hours +':'+ min +':'+ sec, }); }writeFiles = async () => { this.getDate() try { for(let i = 0; i < 1; i++){ count = count + 1; console.log(count); RNFS.appendFile(path, ' \n '+ count +' \n '+ this.state.date , 'utf8') .then((success) => { }) } }catch (err) { console.warn("error", err); } } };
In order to use react-native-background-queue + react-native-background-task:
import React, { Component } from 'react';import Mytest from './test';import BackgroundTask from 'react-native-background-task'import {Platform,...} from 'react-native';import queueFactory from 'react-native-queue';BackgroundTask.define(async () => { queue = await queueFactory(); queue.addWorker('background-example', async (id, payload) => { if (payload.name == 'sima') { Mytest.writeFiles() console.log('Hello from a background task ')} }); await queue.start(20000); BackgroundTask.finish();});export default class App extends Component<{}> { constructor(props) { super(props); this.state = { queue: null, data: null, }; this.init(); } async init() { const queue = await queueFactory(); queue.addWorker('background-example', async (id, payload) => { }); this.setState({ queue }); } componentDidMount() { BackgroundTask.schedule(); } makeJob(jobName, payload = {}) { console.log('job is created but will not execute until the above OS background task runs in ~15 min'); this.state.queue.createJob(jobName, payload, { timeout: 5000 }, false); } render() { let output = 'No data loaded from OS background task yet.'; if (this.state.data) { output = JSON.stringify(this.state.data); } return (<View style={styles.container}><Text style={styles.welcome}> Welcome to React Native!</Text><Text>Click buttons below to add OS background task jobs.</Text><Text>Then Close App (task will not fire if app is in focus).</Text><Text>Job will exec in ~15 min in OS background.</Text> {this.state.queue && <Button title={"Press To Queue sima Job"} onPress={ () => { this.makeJob('background-example', { name: 'sima' }) } } /> } {this.state.queue && <Button title={"Press To Queue another Job"} onPress={ () => { this.makeJob('background-example', { name: 'simsim' }) } } /> }<Text>{output}</Text></View> ); }}const styles = StyleSheet.create({ container: { flex: 1, justifyContent: 'center', alignItems: 'center', backgroundColor: '#F5FCFF', }, welcome: { fontSize: 20, textAlign: 'center', margin: 10, },});
And here is test.js:
var RNFS = require('react-native-fs');var path = RNFS.DocumentDirectoryPath +'/test.txt';var count = 0;const Mytest = { writeFiles: () => { var that = this; var date = new Date().getDate(); //Current Date var month = new Date().getMonth() + 1; //Current Month var year = new Date().getFullYear(); //Current Year var hours = new Date().getHours(); //Current Hours var min = new Date().getMinutes(); //Current Minutes var sec = new Date().getSeconds(); //Current Seconds var date = date +'/'+ month +'/'+ year +''+ hours +':'+ min +':'+ sec try { for(let i = 0; i < 1; i++){ count = count + 1; console.log(count); RNFS.appendFile(path, ' \n '+ count +' \n '+ date , 'utf8') .then((success) => { console.log('FILE WRITTEN!'); }) } }catch (err) { console.warn("error", err); } } } export default Mytest;
