react-native - 如何在 react-native 版本 3+ 的 App.js 文件中添加构造函数

Question

我是 react-native 开发的新手。我想在 app.js 文件中添加构造函数，并且使用底部选项卡导航器组件。由于 App 容器，我被困在哪里添加构造函数以及它是如何调用的。

查询：- - 如何在此类中添加构造函数和方法。

我的代码如下（App.js）文件。

import React from 'react';
import { StyleSheet, Text, View, TouchableHighlight, TextInput } from 'react-native';
import { f, auth, database, storage } from './config/config.js';
import { createBottomTabNavigator, createAppContainer } from 'react-navigation';
import feed from './app/screens/feed.js';
import upload from './app/screens/upload.js';
import profile from './app/screens/profile.js';

const MainStack = createBottomTabNavigator (
  {
     Feed: { screen: feed },
     Upload: { screen: upload },
     Profile: { screen: profile }
  }
  );

const App = createAppContainer(MainStack);

export default App;

如果有人对此有想法。请帮我。

提前致谢！！

标签： react-nativeconstructorreact-native-android

Answer 1

编辑：

import React from 'react';
import { StyleSheet, Text, View, TouchableHighlight, TextInput } from 'react-native';
import { f, auth, database, storage } from './config/config.js';
import { createBottomTabNavigator, createAppContainer } from 'react-navigation';
import feed from './app/screens/feed.js';
import upload from './app/screens/upload.js';
import profile from './app/screens/profile.js';

const MainStack = createBottomTabNavigator (
{
  Feed: { screen: feed },
  Upload: { screen: upload },
  Profile: { screen: profile }
}); 

const AppContainer = createAppContainer(MainStack);

export default class App extends React.Component {
  constructor(props){
    super(props)
  }

  render() {
      return <AppContainer/>
  }
}