求助求助 你们谁用redux出现过这个错？ 求大神回复

#1 
Invariant Violation: Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: undefined. You likely forgot to export your component from the file it's defined in.

This error is located at:
    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)
createFiberFromElementType
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:1016:100
createFiberFromElement
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:996:47
reconcileSingleElement
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:1448:51
reconcileChildFibers
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:1508:63
reconcileChildrenAtPriority
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:1688:78
reconcileChildren
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:1685:40
updateHostComponent
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:1752:39
beginWork
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:1839:43
performUnitOfWork
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:2569:33
workLoop
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:2595:141
_invokeGuardedCallback
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:75:23
invokeGuardedCallback
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:49:40
performWork
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:2634:41
scheduleUpdateImpl
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:2768:101
scheduleUpdate
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:2751:38
scheduleTopLevelUpdate
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:3048:91
updateContainer
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:3059:39
render
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\Renderer\ReactNativeFiber-dev.js:4483:53
renderApplication
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\ReactNative\renderApplication.js:34:4
run
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\ReactNative\AppRegistry.js:117:10
runApplication
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\ReactNative\AppRegistry.js:191:26
__callFunction
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:306:47
<unknown>
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:108:26
__guard
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:269:6
callFunctionReturnFlushedQueue
    D:\learn\React Native\Practice\FirstApp\node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:107:17

reducer/index.js

import { combineReducers } from 'redux';

import news from './news/index.js';

const rootReducer = combineReducers({
    news
});

export default rootReducer;

sore:

import { createStore,applyMiddleware } from 'redux';
import thunk from 'redux-thunk';
import rootReducer from '../reducers/index.js'

const createStoreWithMiddleware = applyMiddleware(thunk)(createStore);

export default function getStore(initialState){
    const store = createStoreWithMiddleware(rootReducer, initialState);

    return store;
}

root.js

import React from 'react';
import { Provider } from 'react-redux';
import getStore from './store/index.js';

import App from './containers/components/App.js';

const store =  getStore();

const Root = () =>
    (
        <Provider store={store}>
            <App/>
        </Provider>
    );

export default Root;

App.js

const App = DrawerNavigator({
    App: {
        screen:AppStack,
        navigationOptions: {
            title: '',
            tabBarLabel: '',
        },
    },
    MyScreen: {
        screen:MyStack,
    },
    WelfareStack:{
        screen:WelfareStack,
    }
},{
    drawerWidth:250,
    contentComponent: props => <ScrollView><DrawerContent {...props}/></ScrollView>,
    contentOptions:{
        activeTintColor:'white',
        activeBackgroundColor: '#C4C4C4', // 选中背景颜色
        inactiveTintColor: '#4F4F4F',  // 未选中文字颜色
        inactiveBackgroundColor: '#fff', // 未选中背景颜色
    }
});

const DrawerContent = (props) => {
    return(
        <View style={styles.container}>
            <View style={styles.header}>
                <Image source={require('../../../public/image/2.png')} style={styles.bgimg}>
                    <Text style={styles.welcome}>欢迎</Text>
                </Image>
            </View>
            <DrawerItems {...props}/>
        </View>
    )
}

export default App

部分代码

#2

求大神门帮我看看:sweat:

#3

字面意思是有个组件的地方实际上传了 undefined, 居然要一个个查过去了

#4

看看哪个组件已经写好的，但是没有export出去。或者类/函数也看看是否没有定义就直接用的。

1 Like
#5

谢谢了。已经找到了

import { AppRegistry } from 'react-native';
import Root from './app/root'

AppRegistry.registerComponent('FirstApp', () => Root);

这段代码错了

#6

谢谢:relaxed:

#7

怎么解决的， 我才开始看。