首页 > 解决方案 > RefreshControll 数据重复每次在 React Native 中拉动以刷新 ScrollView

问题描述

描述
我在 React Native 中实现了一个拉取请求RequestController,每次我拉动刷新相同的数据时,都会一遍又一遍地添加到平面列表中。我实现的拉取请求不在平面列表中,而是在ScrollView包裹FlatList.

行动

import React, { Component } from 'react';
import { View, StyleSheet, Text, Button, Modal, Dimensions, ScrollView, TextInput, TouchableOpacity, StatusBar, Image, Platform, TouchableNativeFeedback,FlatList, ImageBackground, RefreshControl } from 'react-native';
import axios from 'axios';
class HomeScreen extends Component{
    state = {
        refreshing: false,
    }
    componentDidMount(){
        this.searchApi();
    }
    searchApi = async() => {
        const response = await axios.get('http://73udkYid.ngrok.io/api/v1/products',{
                headers: {
                    "x-auth-token":"eyJfaWQiOiI1ZdfjzZmM4YjIwYjBjZDQyMmJkNzUiLCJpYXQiOjE2MD"
                }
            }
        );
        this.setState({results: [...this.state.results, response.data]});
    }
    _onRefresh = () => {
        this.setState({refreshing: true});
        this.searchApi().then(() => {
          this.setState({refreshing: false});
        });
    }
    render(){
        let finalGames = [];
            this.state.results.forEach(obj => {
                Object.keys(obj).forEach(key => {
                finalGames.push(obj[key]);
            });
        });
        return (
        <ScrollView style={{flex: 1,backgroundColor: 'white',}}
                refreshControl = {
                    <RefreshControl 
                        refreshing = { this.state.refreshing }
                        onRefresh={this._onRefresh}
                    />
                }
            >  
       
        <FlatList 
            data = { finalGames }
            keyExtractor = {(item, index) => index.toString()}
            renderItem = { ({item: itemData}) => {
                if(itemData.empty == true){
                    return <View style = {[styles.item,styles.itemInvisible]}/>
                }
                return (
                    <View style = {{ flex: 1, margin: 4}}>
                    <View style = {styles.item}> 
                    <TouchableOpacity 
                        onPress = {() => {
                            this.setState({ viewController: this.state.viewController++ })
                            this.props.navigation.navigate(
                                "ProductDetail", {
                                itemDataDetail: itemData,
                                businessname:this.props.navigation.state.params.businessname,
                                viewController: this.state.viewController,
                             })
                         }}>
                    <View>
                        <ImageBackground 
                            source={{ uri: itemData.photo }}
                            style={{ width:'100%',aspectRatio: 1, borderRadius: 15, borderWidth:1, borderColor:"#FAFAFA", overflow: 'hidden'}}>
                        </ImageBackground>
                        <View style = {{ margin: 5}}>
                        <Text style = {{color: '#2E2E2E', fontWeight:"bold"}} numberOfLines={1}>{itemData.item}</Text>
                        <Text style = {{color: '#2E2E2E', fontSize: 12, fontWeight:"normal", alignSelf: 'flex-start'}} numberOfLines={1}>Available now | Sold out</Text>
                        <Text style = {{color: 'white', fontSize: 18, fontWeight:"bold", backgroundColor:"#DE1F38", alignSelf: 'flex-start', paddingHorizontal: 10,paddingVertical:2,borderRadius: 8,overflow: 'hidden', marginTop: 5}} numberOfLines={1}>${itemData.price}</Text>
                    </View>
                    </View>
                    </TouchableOpacity>
                    </View>
                    </View>
            </ScrollView>
          );
    }}/> 
}


每次触发新的拉刷新时输出数据重复

标签: javascriptreact-nativeuirefreshcontrol

解决方案


我假设您的 api-call 返回整个产品列表

此行将 api-response-data 连接到您在组件状态中已有的产品列表

this.setState({results: [...this.state.results, response.data]});

试试这个...

this.setState({ results: response.data });

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