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reactjs - 状态似乎被覆盖而不是合并

转载 作者:行者123 更新时间:2023-12-03 13:27:04 25 4
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我目前正在尝试学习 Redux,我认为我一定是错误地实现了它,因为只有页面上渲染的最后一个组件才真正起作用。我怀疑状态每次都被覆盖。

我关注了this教程仅使用一个数据检索示例,因此我可能只是误解了如何写入状态。

这是我的 reducer 。有什么想法我哪里出错了吗?而且这一切看起来都非常冗长,有没有一种更干燥的方式来写出来?

import Immutable from 'seamless-immutable';
import { combineReducers } from 'redux';
import { routerReducer } from 'react-router-redux';

// Import actions
import {
REQUEST_CONFIG,
GET_CONFIG,
REQUEST_PAGES,
GET_PAGES,
REQUEST_SOCIAL_LINKS,
GET_SOCIAL_LINKS,
REQUEST_NAV,
GET_NAV
} from './actions';

const configInitialState = Immutable({
items: [],
isFetching: false
})

const pagesInitialState = Immutable({
items: [],
isFetching: false
})

const socialLinksInitialState = Immutable({
items: [],
isFetching: false
})

const navInitialState = Immutable({
items: [],
isFetching: false
})

export function config(state = configInitialState, action) {
switch (action.type) {
case GET_CONFIG :
return Immutable(state).merge({
items: action.payload.config[0],
isFetching: false
})
case REQUEST_CONFIG :
return Immutable(state).merge({
isFetching: true
})
default:
return state;
}
}

export function pages(state = pagesInitialState, action) {
switch (action.type) {
case GET_PAGES :
return Immutable(state).merge({
items: action.payload.pages,
isFetching: false
})
case REQUEST_PAGES :
return Immutable(state).merge({
isFetching: true
})
default:
return state;
}
}

export function socialLinks(state = socialLinksInitialState, action) {
switch (action.type) {
case GET_SOCIAL_LINKS :
return Immutable(state).merge({
items: action.payload.socialLinks,
isFetching: false
})
case REQUEST_SOCIAL_LINKS :
return Immutable(state).merge({
isFetching: true
})
default:
return state;
}
}

export function nav(state = navInitialState, action) {
switch (action.type) {
case GET_NAV :
return Immutable(state).merge({
items: action.payload.nav,
isFetching: false
})
case REQUEST_NAV :
return Immutable(state).merge({
isFetching: true
})
default:
return state;
}
}

const rootReducer = combineReducers({
config,
pages,
socialLinks,
nav,
routing: routerReducer
});

export default rootReducer;

为了以防万一,这里也是我的一个组件的示例:

import React from 'react';
import { Link } from 'react-router';
import { connect } from 'react-redux';
import { navLoad } from '../../../scripts/actions';

export default class HeaderNav extends React.Component {
componentWillMount() {
const { dispatch } = this.props;
dispatch(navLoad());
}

render() {
const { nav } = this.props;
const navitems = nav && nav.items ? nav.items.asMutable().map((item) => {
if(item.inNav === 'header' || item.inNav === 'both') {
return <li key={item._id}><Link to={item.slug}>{item.name}</Link></li>
}
}) : null;
if(nav.isFetching) {
return(
<section class="loader">
<span>Content is loading...</span>
</section>
)
} else {
return(
<nav class="c-primary-nav">
<span class="c-primary-nav_toggle">Menu</span>
<ul>
{ navitems }
</ul>
</nav>
)
}
}
}

function select(state) {
const { nav } = state;
return {
nav
};
}

export default connect(select)(HeaderNav);

这里是调用组件的地方:

import React from 'react';
import HeaderNav from './Header/nav.jsx';
import SocialLinks from './Header/socialLinks.jsx';

export default class Header extends React.Component {
render() {
return(
<header class="c-global-header" role="banner">
<HeaderNav />
<SocialLinks />
</header>
)
}
}

更新:我仍然希望得到这个问题的答案,因为它仍然困扰着我,我现在对代码做了一些修改,但没有效果。您可以在这里查看我的完整代码库:https://github.com/alexward1981/portfolio-react (所有相关内容都在“src”文件夹中)

最佳答案

我刚刚遇到了同样的问题,问题出在 reducer 中,而不是默认 switch case 部分中的返回状态,而是返回初始状态。

export const getAppShopReducer = (state = initialState, action) => {
switch (action.type) {
case types.FETCH_APP_SHOP_SUCCESS:

return state
.set('loading', false)
.set('user', action.payload.user)
.set('appShop', action.payload.appShop)
.set('shop', action.payload.shop)
;

case types.FETCH_APP_SHOP_REQUEST:

return initialState.set('loading', true);

default:
return state; // Here's the problem, it was `initialState`;
}
};

关于reactjs - 状态似乎被覆盖而不是合并,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/36777619/

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