einfache api Beispiel holen nicht funktioniert

Question

Ich bin neu in reagieren-native, ist hier mein Code:

import React, { Component } from 'react'; 
import { 
    AppRegistry, 
    StyleSheet, 
    Text, 
    View 
} from 'react-native'; 

class FetchExample extends Component { 
    constructor() { 
     super(); 
     this.state = { 
      date: '' 
     } 
    } 
    render() { 
     return (
      <View style={styles.container}> 
       <Text>{}</Text> 
      </View> 
     ); 
    } 
    componentWillMount() { 
     fetch("http://date.jsontest.com/") 
      .then((response) => response.json()) 
      .then((responseData) => { 
       console.log('a'); 
       this.setState({date: responseData.date}); 
      }) 
      .done(); 
    } 
} 

const styles = StyleSheet.create({ 
    container: { 
     flex: 1, 
     justifyContent: 'center', 
     alignItems: 'center', 
     backgroundColor: '#F5FCFF', 
    } 
}); 

AppRegistry.registerComponent('ak',() => FetchExample); 

Und hier wird das Protokoll Fehler:

10:53:38 PM: Warning: React.createElement: type is invalid -- expected a string (for built-in components) or a class/function (for composite components) but got: object. You likely forgot to export your component from the file it's defined in. Check the render method of AwakeInDevApp . in AwakeInDevApp (at registerRootComponent.js:36) in RootErrorBoundary (at registerRootComponent.js:35) in ExpoRootComponent (at renderApplication.js:35) in RCTView (at View.js:113) in View (at AppContainer.js:102) in RCTView (at View.js:113) in View (at AppContainer.js:126) in AppContainer (at renderApplication.js:34) - node_modules/fbjs/lib/warning.js:33:20 in printWarning - ... 24 more stack frames from framework internals

Answer 1

Sie müssen Ihre Komponente exportieren. wie dieser

export default class FetchExample extends Component {