我正在尝试在React中创建一个产品列表,可以在其中添加和删除产品。
我开始研究如何使用redux框架/平台执行此操作并做出本地反应
我已经有一个功能productList
容器,product
组件和cartList
,cartProduct
组件。
我的问题是:
产品:我只能添加产品,而不能删除
购物车:反之亦然+购物车未更新购物车项目的状态。
我添加了bindActionCreator,但尚不知道如何将其应用于我的productList。
我期望发生什么? 我正在尝试在同一容器/组件中的反应存储中添加和删除产品。
我该怎么做?我的方法正确还是完全错误?
在此先谢谢您。
ProductActionCreators
export const ADD_TO_CART = 'ADD_TO_CART'
export const REMOVE_FROM_CART = 'REMOVE_FROM_CART'
export function addItemToCart(row) {
return {
type:'ADD_TO_CART',
payload: row, qty
}
}
export function removeTodo(row) {
return {
type:'REMOVE_FROM_CART' ,
payload: row, qty
}
}
产品列表(简体)
import React from 'react';
import { Component } from 'react';
import {
View,
StyleSheet,
Text
} from 'react-native';
import Products from '../components/Products';
import { bindActionCreators} from 'redux';
import { connect } from 'react-redux';
import * as ProductActionCreators from '../actions/ProductActionCreators'
export class ProductList extends React.Component {
static navigationOptions = {
header: null,
};
constructor(props) {
super(props);
const { rows } = this.props.navigation.state.params;
const arrays = Object.values( {rows});
this.state = {
arrays,
filteredProducts: arrays,
};
const { dispatch } = props
this.boundActionCreators = bindActionCreators(ProductActionCreators, dispatch)
console.log(this.boundActionCreators)
}
render() {
return (
<View style={styles.container} >
<Text style={styles.title} >
{this.state.arrays[0].name}
</Text>
<Products products={this.state.arrays[0].data} onPress=
//Trying to change this to multiple actions
{this.props.addItemToCart}/>
</View>
)
}
}
const qty = 0;
const mapDispatchToProps = (dispatch) =>{
//need to add BindActionCreator
return{
addItemToCart:(row) => dispatch({
type:'ADD_TO_CART', payload: row, qty
}),
removeItem:(product) => dispatch ({
type:'REMOVE_FROM_CART' , payload: product, qty
})
}
}
export default connect(null, mapDispatchToProps) (ProductList);
产品(简体)
import React, { Component } from "react";
import {
View,
Text,
TouchableOpacity,
TextInput,
FlatList,
} from "react-native";
import Icon from "react-native-vector-icons/Ionicons";
class Products extends Component {
constructor(props) {
super(props);
const { products } = this.props;
this.state = {
products,
filteredProducts: products,
};
}
renderProducts = (products) => {
return (
<View key={products.index}>
<View>
<Icon name={products.item.icon} color="#DD016B" size={25} />
</View>
<View>
<Text style={styles.name}>
{products.item.name}
</Text>
<Text>
€ {products.item.price}
</Text>
</View>
<View style={styles.buttonContainer}>
<TouchableOpacity onPress={() => this.props.onPress(products.item)} >
<Icon name="ios-add" color="white" size={25} />
</TouchableOpacity>
<TouchableOpacity onPress={() => this.props.onPress(products.item)} >
<Icon name="ios-remove" color="white" size={25} />
</TouchableOpacity>
</View>
</View>
)
}
render() {
return (
<View>
<FlatList
style={styles.listContainer}
data={this.state.filteredProducts}
renderItem={this.renderProducts}
keyExtractor={(item, index) => index.toString()}
/>
</View>
);
}
}
export default Products;
减少器/购物车
const cartItems = (state = [], action) => {
switch (action.type)
{
case 'ADD_TO_CART':
if (state.some(cartItem => cartItem.id === action.payload.id)) {
// increase qty if item already exists in cart
return state.map(cartItem => (
cartItem.id === action.payload.id ? { ...cartItem, qty: cartItem.qty + 1 } : cartItem
));
}
return [...state, { ...action.payload, qty: 1 }];
// else add the new item to cart
case 'REMOVE_FROM_CART':
return state
.map(cartItem => (cartItem.id === action.payload.id ? { ...cartItem, qty: cartItem.qty - 1 } : cartItem))
.filter(cartItem => cartItem.qty > 0);
}
return state
}
export default cartItems
商店/索引
import {createStore} from 'redux';
import cartItems from '../reducers/carItems';
export default store = createStore(cartItems)
应用程序结构(简化)
Main folder
↳
Containers(folder)
↳
ProductsList.js
CartList.js
Components(folder)
↳
Product.js
cartProduct.js
Reducers(folder)
↳
carItems.js
Actions(folder)
↳
ProductActionCreators.js
Navigation(folder)
↳
AppNavigator,js
MainTabNavigator.js
Assets(folder for images etc.)
Store(folder)
↳
index.js
App.JS
Data.JS (using static JSON file for this development phase)
答案 0 :(得分:3)
您有两个不同的动作addItemToCart
和removeItem
,它们是在mapDispatchToProps中定义的。现在,您已指定要连接的mapDispatchToProps参数,则不可以使用调度方法作为对已连接组件的支持,而是只能使用mapDispatchToProps返回的方法
第二,,您无需使用bindActionCreators
,而且绝对不需要在组件中使用。 MapDispatchToProps
可以只是一个对象,connect将在内部使用调度。
第三,您需要将添加和删除操作都传递给子组件。
第四,您可以简单地将多个操作传递给产品组件
您的代码看起来像
ProductActionCreators.js
export const ADD_TO_CART = 'ADD_TO_CART'
export const REMOVE_FROM_CART = 'REMOVE_FROM_CART'
export function addItemToCart(row) {
return {
type:'ADD_TO_CART',
payload: row
}
}
export function removeItem(item) {
return {
type:'REMOVE_FROM_CART' ,
payload: item
}
}
产品列表
import React from 'react';
import { Component } from 'react';
import {
View,
StyleSheet,
Text
} from 'react-native';
import Products from '../components/Products';
import { connect } from 'react-redux';
import { addItemToCart, removeItem } from '../actions/ProductActionCreators';
export class ProductList extends React.Component {
static navigationOptions = {
header: null,
};
constructor(props) {
super(props);
const { rows } = this.props.navigation.state.params;
const arrays = Object.values( {rows});
this.state = {
arrays,
filteredProducts: arrays,
};
}
render() {
return (
<View style={styles.container} >
<Text style={styles.title} >
{this.state.arrays[0].name}
</Text>
<Products products={this.state.arrays[0].data} addItemToCart={this.props.addItemToCart} removeItem={this.props.removeItem}/>
</View>
)
}
}
const mapDispatchToProps = {
addItemToCart,
removeItem
}
export default connect(null, mapDispatchToProps) (ProductList);
产品
import React, { Component } from "react";
import {
View,
Text,
TouchableOpacity,
TextInput,
FlatList,
} from "react-native";
import Icon from "react-native-vector-icons/Ionicons";
class Products extends Component {
constructor(props) {
super(props);
const { products } = this.props;
this.state = {
products,
filteredProducts: products,
};
}
renderProducts = (products) => {
return (
<View key={products.index}>
<View>
<Icon name={products.item.icon} color="#DD016B" size={25} />
</View>
<View>
<Text style={styles.name}>
{products.item.name}
</Text>
<Text>
€ {products.item.price}
</Text>
</View>
<View style={styles.buttonContainer}>
<TouchableOpacity onPress={() => this.props.addItemToCart(products.item)} >
<Icon name="ios-add" color="white" size={25} />
</TouchableOpacity>
<TouchableOpacity onPress={() => this.props.removeItem(products.item)} >
<Icon name="ios-remove" color="white" size={25} />
</TouchableOpacity>
</View>
</View>
)
}
render() {
return (
<View>
<FlatList
style={styles.listContainer}
data={this.state.filteredProducts}
renderItem={this.renderProducts}
keyExtractor={(item, index) => index.toString()}
/>
</View>
);
}
}
export default Products;
答案 1 :(得分:1)
在大多数情况下,代码看起来还不错。
ProductList中的react-redux连接部分看起来不对。 qty始终为0。应为1。
此外,应该存在mapStateToProps以便从购物车中获取产品。
答案 2 :(得分:1)
在您的ProductList
中,我将按照以下方式进行操作绑定:
const mapDispatchToProps = (dispatch) =>{
return bindActionCreators({
addItemToCart: (row, qty) => dispatch({
type:'ADD_TO_CART', payload: {row, qty}
}),
removeItem: (product, qty) => dispatch({
type:'REMOVE_FROM_CART' , payload: {product, qty}
})
})
}
export default connect(null, mapDispatchToProps)(ProductList);
从组件的构造函数中删除操作绑定,因为这是不必要的。
您可能希望将代码分成Container
/ Component
/ HOC方法,因为我发现它使代码更易于阅读。当您在单独的文件中定义了操作时,我也将导入这些操作而不是重新声明它们。
如果遵循此建议,您将得到以下结果:
container.js
import { bindActionCreators } from 'redux';
import ProductList from './product-list';
// Actions
import { addItemToCart, removeItem } from './actions';
function mapStateToProps(state) {
return {}
}
function mapDispatchToProps(dispatch) {
return bindActionCreators({
addItemToCart,
removeItem,
})
}
export default connect(mapStateToProps, mapDispatchToProps)(ProductList);
product-list.js
import React from 'react';
import { View, Text } from 'react-native';
import Products from '../components/Products';
export class ProductList extends React.Component {
static navigationOptions = {
header: null,
};
constructor(props) {
super(props);
const { rows } = this.props.navigation.state.params;
const arrays = Object.values( {rows});
this.state = {
arrays,
filteredProducts: arrays,
};
this.handleProductPress = this.handleProductPress.bind(this);
}
handleProductPress(e) {
e.preventDefault();
// This is pseudo code...
this.props.addItemToCart(e.target.value, 1);
return;
}
render() {
return (
<View style={styles.container} >
<Text style={styles.title} >
{this.state.arrays[0].name}
</Text>
<Products products={this.state.arrays[0].data} onPress={this.handleProductPress} />
</View>
)
}
}
export default ProductList;
试玩一下,看看你如何过关。