反应-Redux |产品列表 |使用 BindActionCreator 添加/删除

Question

我正在尝试在 React 中创建一个产品列表，我可以在其中添加和删除产品。

我开始研究如何使用redux 框架/平台和原生反应来做到这一点

我已经有一个函数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，不能删除

购物车：反之亦然 + 购物车不会更新购物车物品的状态。

我已经添加了 bindActionCreator，但还不知道如何将它应用到我的 productList 中。

我预计会发生什么？ 我正在尝试在同一个容器/组件中的反应存储中添加和删除产品。

我该怎么做？我的方法是正确的还是完全错误的？

提前谢谢你。

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;

reducers/cartItems

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)

Answer 1

您有两个不同的操作，addItemToCart、removeItem，您在 mapDispatchToProps 中定义它们。现在你指定了一个 mapDispatchToProps 参数来连接，dispatch 方法不能作为连接组件的 prop 使用，而是 mapDispatchToProps 返回的方法只可用

第二，你不需要使用bindActionCreators，而且绝对不用在组件中。 MapDispatchToProps 可以只是一个对象，connect 会在内部使用 dispatch。

第三，您需要将添加和删除操作都传递给子组件。

第四您可以将多个操作简单地作为 prop 传递给 Product 组件

你的代码看起来像

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;

Answer 2

大部分代码看起来都不错。

ProductList 中的 react-redux 连接部分看起来不正常。 qty 始终为 0。应该为 1。

此外，应该存在 mapStateToProps 以从购物车中获取产品。

Answer 3

在您的ProductList 中，我会像这样处理动作绑定：

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。

您可能希望将代码拆分为 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您的操作时，我也会导入这些而不是重新声明它们。

如果您遵循此建议，您最终会得到以下结果：

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;

试一试，看看你的表现如何。