React-native-background-fetch
$ npm install --save react-native-background-fetch
kells Kamuzu
$ npm install --save react-native-background-fetch$ react-native unlink react-native-background-fetchimport React from 'react';
import {
SafeAreaView,
StyleSheet,
ScrollView,
View,
Text,
FlatList,
StatusBar,
} from 'react-native';
import {
Header,
Colors
} from 'react-native/Libraries/NewAppScreen';
import BackgroundFetch from "react-native-background-fetch";
class App extends React.Component {
constructor(props) {
super(props);
this.state = {
events: []
};
}
componentDidMount() {
// Initialize BackgroundFetch ONLY ONCE when component mounts.
this.initBackgroundFetch();
}
async initBackgroundFetch() {
// BackgroundFetch event handler.
const onEvent = async (taskId) => {
console.log('[BackgroundFetch] task: ', taskId);
// Do your background work...
await this.addEvent(taskId);
// IMPORTANT: You must signal to the OS that your task is complete.
BackgroundFetch.finish(taskId);
}
// Timeout callback is executed when your Task has exceeded its allowed running-time.
// You must stop what you're doing immediately BackgroundFetch.finish(taskId)
const onTimeout = async (taskId) => {
console.warn('[BackgroundFetch] TIMEOUT task: ', taskId);
BackgroundFetch.finish(taskId);
}
// Initialize BackgroundFetch only once when component mounts.
let status = await BackgroundFetch.configure({minimumFetchInterval: 15}, onEvent, onTimeout);
console.log('[BackgroundFetch] configure status: ', status);
}
// Add a BackgroundFetch event to <FlatList>
addEvent(taskId) {
// Simulate a possibly long-running asynchronous task with a Promise.
return new Promise((resolve, reject) => {
this.setState(state => ({
events: [...state.events, {
taskId: taskId,
timestamp: (new Date()).toString()
}]
}));
resolve();
});
}
render() {
return (
<>
<StatusBar barStyle="dark-content" />
<SafeAreaView>
<ScrollView
contentInsetAdjustmentBehavior="automatic"
style={styles.scrollView}>
<Header />
<View style={styles.body}>
<View style={styles.sectionContainer}>
<Text style={styles.sectionTitle}>BackgroundFetch Demo</Text>
</View>
</View>
</ScrollView>
<View style={styles.sectionContainer}>
<FlatList
data={this.state.events}
renderItem={({item}) => (<Text>[{item.taskId}]: {item.timestamp}</Text>)}
keyExtractor={item => item.timestamp}
/>
</View>
</SafeAreaView>
</>
);
}
}
const styles = StyleSheet.create({
scrollView: {
backgroundColor: Colors.lighter,
},
body: {
backgroundColor: Colors.white,
},
sectionContainer: {
marginTop: 32,
paddingHorizontal: 24,
},
sectionTitle: {
fontSize: 24,
fontWeight: '600',
color: Colors.black,
},
sectionDescription: {
marginTop: 8,
fontSize: 18,
fontWeight: '400',
color: Colors.dark,
},
});
export default App;