## 源碼 ~~~ /** * Sample React Native App * https://github.com/facebook/react-native */ 'use strict'; var React = require('react-native'); var { AppRegistry, StyleSheet, Text, View, } = React; var helloworld = React.createClass({ render: function() { return ( <View style={styles.container}> <Text style={styles.welcome}> Welcome to React Native! </Text> <Text style={styles.instructions}> To get started, edit index.ios.js </Text> <Text style={styles.instructions}> Press Cmd+R to reload,{'\n'} Cmd+D or shake for dev menu </Text> </View> ); } }); var styles = StyleSheet.create({ container: { flex: 1, justifyContent: 'center', alignItems: 'center', backgroundColor: '#F5FCFF', }, welcome: { fontSize: 20, textAlign: 'center', margin: 10, }, instructions: { textAlign: 'center', color: '#333333', marginBottom: 5, }, }); AppRegistry.registerComponent('hellowrold',() => helloworld); ~~~ ## 問題 `AppRegistry.registerComponent('hellowrold',() => helloworld);`中`registerComponent`方法的第一個參數`hellowrold`參數一定要跟項目名一樣，否則就會報錯。  ## 總結 新建項目分5步： ## 引入react-native ~~~ var React = require('react-native'); ~~~ ## 定義組件 ~~~ var { AppRegistry, StyleSheet, Text, View, } = React; ~~~ ## 定義界面控件 ~~~ var helloworld = React.createClass({}); ~~~ ## 定義控件樣式 ~~~ var styles = StyleSheet.create({}); ~~~ ## 為項目注冊界面 ~~~ AppRegistry.registerComponent('項目名',() =>界面); ~~~