TypeError:未定义不是对象(计算'store.getState')

Question

我正在学习让我们构建:带有React本机+ Redux的加密本地移动应用程序教程。

当我在App.js中创建我的商店时，这个应用程序运行良好。

import { createStore, applyMiddleware, compose } from 'redux';
import devTools from 'remote-redux-devtools';
import React, { Component } from 'react';
import { Platform, View } from 'react-native';
import { Provider } from 'react-redux';
import promise from 'redux-promise';
import thunk from 'redux-thunk';
import logger from 'redux-logger';

import { Header, CryptoContainer } from './src/components';
import rootReducer from './src/reducers';    

const middleware = applyMiddleware(thunk, promise, logger);

const Store = createStore(rootReducer, compose(middleware, devTools({
  name: Platform.OS,
  hostname: 'localhost',
  port: 5678
}), ));

export default class App extends Component {
  render() {
    return (
      <Provider store={Store}>
        <View>
          <Header />
          <CryptoContainer />
        </View>
      </Provider>
    );
  }
}

但是当我将存储逻辑移动到一个新文件./src/Store.js时，

import { Platform } from 'react-native';    
import { createStore, applyMiddleware, compose } from 'redux';
import devTools from 'remote-redux-devtools';
import promise from 'redux-promise';
import thunk from 'redux-thunk';
import logger from 'redux-logger';

import rootReducer from './reducers';

const middleware = applyMiddleware(thunk, promise, logger);

const Store = createStore(rootReducer,compose(middleware,devTools({
            name: Platform.OS,
            hostname: 'localhost',
            port: 5678
        }),
    )
);

export default Store;

并在App.js中使用它，如

import React, { Component } from 'react';
import { View } from 'react-native';
import { Provider } from 'react-redux';

import { Header, CryptoContainer } from './src/components';
import { Store } from './src/Store';

export default class App extends Component {
  render() {
    return (
      <Provider store={Store}>
        <View>
          <Header />
          <CryptoContainer />
        </View>
      </Provider>
    );
  }
}

我得到了

TypeError:未定义不是对象(计算'store.getState')

是什么导致我的构建(expo start)在导入Store.js时失败

Answer 1

看来导入语句不对。它应该是：

import Store from './src/Store';

Answer 2

如果您要导入一个single named export

例如，在您已经完成export const MyComponent = () => {}的地方，您将导入它就像

import { MyComponent } from "./MyComponent"

如果您要导入一个default export

例如，在您已经完成const MyComponent = () => {} export default MyComponent的地方，您将导入它就像

import MyDefaultComponent from "./MyDefaultExport"

Answer 3

我得到这个错误是因为我从我的主App文件导出了错误的组件。

我是在出口这个：

import React from 'react'
import { Provider } from 'react-redux'
import { createAppContainer } from 'react-navigation'
import Navigator from './src/components/Navigator'
import { store } from './src/store'

const App = createAppContainer(Navigator);

const Wrapped = props => (
  <Provider store={store}>
    <App />
  </Provider>
)

export default Provider; // wrong!

最后一行应是：

export default Wrapped; // right!