Async/Await is a new syntax for writing asynchronous code in JavaScript. Support was added in React Native 0.10 and it’s now reached TC39 stage 3 (candidate).
Example
In this example using the promise returning fetch polyfill. We will display the React Native GitHub star count.
const URL = "https://api.github.com/repos/facebook/react-native"; class StarCount extends Component { constructor() { super(); this.state = {stars: "?"}; } componentDidMount() { this.fetchData().done(); } async fetchData() { const response = await fetch(URL); const json = await response.json(); const stars = json.stargazers_count; this.setState({stars}); } render() { return ( <View style={styles.container}> <Text style={styles.text}> React Native has {this.state.stars} stars </Text> </View> ); } } Async / await works with any Promise based API or one of your creation.
const getStars = () => new Promise(resolve => { const FIVE_SECONDS = 5000; // Simulate async operation setTimeout(() => resolve(1234), FIVE_SECONDS); }); const fetchData = async () => { const stars = await getStars(); // Do something with stars }; 
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