我是React/Redux的新手。 Reduce Chrome devtools告诉我,我正在成功创建和修改状态。然而,虽然控制台日志“dah state”运行并令人满意地告诉我,我的状态中有正确的信息,但我并未在此处映射到道具。由于某种原因,mapStateToProps没有映射到道具
我不完全确定我的reducer是否制作正确,但我怀疑这是因为我创建了新状态,即使它没有映射到道具。
我也相当肯定mapStateToProps,在它运行时,不会触发重新呈现
这里是我的相关容器
import React, { Component, PropTypes } from 'react';
import TopicsGrid from '../components/TopicsGrid.jsx';
import { connect } from 'react-redux';
import { fetchTopics } from '../actions/topics';
import Main from '../components/Main.jsx';
class AboutContainer extends React.Component {
constructor(props) {
super(props);
this.state = {
topics: [{
title: '',
description: '',
link: '',
src: '',
message: '',
selected: false,
_id: ''
}]
}
}
onChange = (action) => {
this.props.dispatch(action);
}
componentDidMount() {
fetchTopics();
}
componentWillReceiveProps(nextProps) {
console.log('nextProps', nextProps)
this.setState({
topics: nextProps.topics
})
}
render() {
console.log('PROPS', this.props)
return (
<div className="container">
<TopicsGrid
topics={this.state.topics}
onChange={this.onChange}/>
</div>
);
}
};
AboutContainer.propTypes = {
dispatch: PropTypes.func.isRequired,
topics: PropTypes.array.isRequired
};
AboutContainer.defaultProps = {
state: {
topics: [{
title: '',
description: '',
link: '',
src: '',
message: '',
selected: false,
_id: ''
}]
}
};
const mapDispatchToProps = (dispatch) => {
return {
dispatch: dispatch
}
}
const mapStateToProps = (state) => {
console.log('dah state', state)
return Object.assign({}, state, {
topics: state.topics.topics
})
}
export default connect(mapStateToProps, mapDispatchToProps)(AboutContainer);
这里是我的减速器
import * as types from '../constants/action-types';
import * as SectionNames from '../constants/section-names';
const initialState = {
topics: []
}
export default function about(state = initialState, action) {
if (action.section !== SectionNames.TOPICS) {
return state;
}
let mods = {};
switch (action.type) {
case types.FETCH_TOPICS_SUCCESS:
mods = {
topics: action.topics
}
// return Object.assign({}, state, {
// topics: action.topics
// });
break;
case types.FETCH_TOPICS_ERROR:
mods = {
topics: action.topics
}
// return Object.assign({}, state, {
// topics: action.topics
// });
break;
case types.TOPIC_SELECTED:
console.log('selected')
//topic can be selected or unselected
//only one topic can be selected at once.
mods = {
topics: action.topics
}
mods.topics[action.index].selected = true;
return Object.assign({}, state, mods);
break;
case types.TOPIC_UNSELECTED:
//topic can be selected or unselected
//only one topic can be selected at once.
mods = {
topics: action.topics
}
mods.topics[action.index].selected = false
break;
default:
return state;
}
return Object.assign({}, state, mods);
}
你应该在国家的部分只是绘制该组件的用途,否则shouldComponentUpdate中的浅支持检查会比它需要的更频繁地返回true,从而使您的应用程序效率降低。相反,从React.PureComponent扩展,浅层检查已经在你身边。如果您可以提供帮助,请避免将道具分配给组件状态。 –