动作不会在React + Redux中触发reducer [英] Action does not trigger a reducer in React + Redux

问题描述

我正在使用react-redux应用程序，由于某种原因，我调用的操作未到达reducer(在该操作中，我目前只有一条log语句).我已附上我认为相关的代码，我们将不胜感激.

I'm working on a react-redux app and for some reason the action I call does not reach the reducer (in which I currently only have a log statement). I have attached the code I feel is relevant and any contributions would be highly appreciated.

在组件中的函数内调用的操作:

Action called within function in component:

onSearchPressed() {
    console.log('search pressed');
    this.props.addToSaved();
}

actions/index.js:

actions/index.js:

var actions = exports = module.exports

exports.ADD_SAVED = "ADD_SAVED";

exports.addToSaved = function addToSaved() {
  console.log('got to ADD_SAVED step 2');
  return {
    type: actions.ADD_SAVED
  }
}

reducers/items.js:

reducers/items.js:

const {
  ADD_SAVED
} = require('../actions/index')

const initialState = {
    savedList: []
}

module.exports = function items(state = initialState, action) {
    let list

    switch (action.type) {
        case ADD_SAVED:
            console.log('GOT to Step 3');
            return state;
        default:
            console.log('got to default');
            return state;
    }
}

reducers/index.js:

reducers/index.js:

const { combineReducers } = require('redux')
const items = require('./items')

const rootReducer = combineReducers({
  items: items
})

module.exports = rootReducer

store/configure-store.js:

store/configure-store.js:

import { createStore } from 'redux'
import rootReducer from '../reducers'

let store = createStore(rootReducer)

onSearchPressed的整个组件:

Entire component for onSearchPressed:

class MainView extends Component {
    onSearchPressed() {
        this.props.addToSaved();
    }
    render() {
        console.log('MainView clicked');
        var property = this.props.property;

        return (
            <View style={styles.container}>
                <Image style={styles.image}
                    source={{uri: property.img_url}} />
                <Text style={styles.description}>{property.summary}</Text>
                <TouchableHighlight style = {styles.button}
                        onPress={this.onSearchPressed.bind(this)}
                        underlayColor='#99d9f4'>
                        <Text style = {styles.buttonText}>Save</Text>
                    </TouchableHighlight>
            </View>
        );
    }
}

module.exports = MainView;

推荐答案

正如Rick Jolly在对问题的评论中提到的那样，您的onSearchPressed()函数实际上并未调度该动作，因为addToSaved()只是返回了一个动作对象-它什么也没派发.

As Rick Jolly mentioned in the comments on your question, your onSearchPressed() function isn't actually dispatching that action, because addToSaved() simply returns an action object - it doesn't dispatch anything.

如果要从某个组件分派操作，则应使用 react-redux 将您的组件连接到Redux.例如:

If you want to dispatch actions from a component, you should use react-redux to connect your component(s) to redux. For example:

const { connect } = require('react-redux')

class MainView extends Component {
  onSearchPressed() {
    this.props.dispatchAddToSaved();
  }
  render() {...}
}

const mapDispatchToProps = (dispatch) => {
  return {
    dispatchAddToSaved: () => dispatch(addToSaved())
  }
}

module.exports = connect(null, mapDispatchToProps)(MainView)

请参阅Redux文档的与React结合使用"部分以了解更多信息信息.

See the 'Usage With React' section of the Redux docs for more information.

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