我之前的 React-Redux 实现是有效的,但是在我尝试使用单独的文件实现 combineReducer 函数之后,抛出了一个我不太理解的错误。希望你们中的一些人可以帮助我!
错误:未捕获的类型错误:this.props.todos.map 不是函数
我对该代码的参考是 Redux-Doc 的异步示例。但是我用另一个例子说明了每个例子的变化都没有记录在文档中。
我将展示的第一个代码是我有(工作):
我的商店
import { createStore, applyMiddleware } from 'redux'
import thunkMiddleware from 'redux-thunk'
import createLogger from 'redux-logger'
import addItem from '../reducers/addItem'
export default function configureStore(preloadedState) {
const store = createStore(
addItem,
preloadedState,
applyMiddleware(thunkMiddleware, createLogger())
)
if (module.hot) {
// Enable Webpack hot module replacement for reducers
module.hot.accept('../reducers', () => {
const nextRootReducer = require('../reducers').default
store.replaceReducer(nextRootReducer)
})
}
return store
}
我的减速机
export default (state = ['Test'], action) => {
switch (action.type){
case 'ADD_ITEM':
//return action.item
return [
...state,
{
id: action.id,
text: action.item
}
]
default:
return state
}
}
行动
export default function addItem(item){
console.log("addTOdo")
return {
type: 'ADD_ITEM',
id: nextTodoId++,
item
}
}
以及最终呈现输入的子组件
import React, { Component, PropTypes } from 'react'
import { connect } from 'react-redux'
export default class TodoList extends Component {
render() {
const posts = this.props
const isEmpty = posts.length === 0
return (
<div>
<h3>Meine Aufgaben</h3>
<ul>
{isEmpty
? <h3>Sie haben noch keinen Todo´s angelegt</h3>
: <h3>Ihre Ergebnisse</h3>
}
{this.props.todos.map((todo, i) => <li key={i}>{todo.text} </li>)}
</ul>
</div>
)
}
}
const mapStateToProp = state => ({todos: state})
export default connect (mapStateToProp)(TodoList)
我有什么改变:
首先,我创建了另一个 Reducers 文件,称为 Index,我在其中导入了 addItem Reducer 并导出了 rootReducer:
import {combineReducers} from 'redux'
import addItem from './addItem'
import getItem from './getItem'
const rootReducer = combineReducers({
addItem,
getItem
})
export default rootReducer
之后,我更改了 Store 以导入 rootReducer 并将其引用放入 Store(只是对 configureStore 的更改):
import rootReducer from '../reducers/index'
const store = createStore(
rootReducer,
preloadedState,
applyMiddleware(thunkMiddleware, createLogger())
)
我不知道是否也需要该信息,但这是我的容器组件:
import React, { Component, PropTypes } from 'react'
import AddTodo from '../components/AddTodo'
import TodoList from '../components/TodoList'
import { connect } from 'react-redux'
import addItem from '../actions/addItem'
import getItems from '../actions/getItems'
class App extends Component {
constructor(props) {
super(props)
this.handleClick = this.handleClick.bind(this)
this.state = {text: ''}
}
handleClick(e){
console.log(e);
const {dispatch} = this.props
dispatch(addItem(e));
}
componentDidMount(){
console.log("COMPONENT MOUNT");
const {dispatch} = this.props
// dispatch(getItems())
}
componentWillReceiveProps(nextProps) {
console.log("GETTT IT");
console.log(nextProps)
}
render() {
return (
<div>
< h1 > Hallo </h1>
<AddTodo handleAddItem={this.handleClick}/>
<TodoList/>
</div>
)
}
}
App.propTypes = {
dispatch: PropTypes.func.isRequired
}
function mapStateToProps(state){
return {
AddTodo
}
}
export default connect (mapStateToProps)(App)
我希望这个问题不是基本的,有人可以帮助我。提前致谢!