BackgroundTask.define not started - react-native

Question

react-native-background-task
I want the code to run back in time. I'm trying to use react-native-background-task. But BackgroundTask.define does not start.
import React from 'react'
import { Text } from 'react-native'
import BackgroundTask from 'react-native-background-task'
BackgroundTask.define(() => {
console.log('Hello from a background task')
BackgroundTask.finish()
})
export default class Home extends React.Component {
componentDidMount() {
BackgroundTask.schedule({
period:1
})
}
render() {
return <Text>Hello world</Text>
}
}

Answer 1

this is due to linking issue
Android
he linking of the library can be done automatically by running:
$ react-native link react-native-background-task
One manual step is still needed -
in your project file android/app/src/main/java/myapp/MainApplication.java, add the following to the end of the onCreate() method:
BackgroundTaskPackage.useContext(this);
iOS
For iOS support, this library relies on version 2.0.x of react-native-background-fetch which can be installed as follows:
$ npm install react-native-background-fetch#2.0.x --save
$ react-native link react-native-background-fetch
This library will behave correctly on iOS as long as react-native-background-fetch is installed alongside it, and has been linked with your project.