如何在使用 contentContainerStyle 等反应本机平面列表中使用 justifyContent 和alignItems

Question

我正在使用本机反应。现在，当我尝试将平面列表置于屏幕中央，并专门为平面列表提供 justifyContent 和alignItems 时，它给了我一个奇怪的动作。另外，以 justifyContent 和alignItems 为中心的contentContainerStyle 也给出了一个奇怪的动作。昨天一整天都在寻找解决方案。我将在下面提供代码和图像。谢谢。

我试图在中心对齐这个平面列表，就像 justfyContent 和alignItems 会做的那样。您可以看到内容向屏幕左侧倾斜。

import React, { useState } from "react";
import { View, Text , Button, FlatList, ActivityIndicator, TouchableOpacity } from "react-native";
import { GlobalStyles } from "../styles/GlobalStyles";
import PokeDetails from "./PokeDetails";
import SearchBarComponent from "../components/SearchBar";
import PokeBanner from "../components/PokeBanner";

class Home extends React.Component {

    constructor(props) {
        super(props);
        this.state = {
            isLoading: true,
            dataSource: [],
        }
    }

    componentDidMount() {
        fetch(`https://pokeapi.co/api/v2/pokemon/?limit=27`)
            .then((res)=> res.json())
            .then((response)=> {
                this.setState({
                    isLoading: false,
                    dataSource: response.results,
                })
                console.log("RESPONSE",response)
                console.log("RESPONSE.RESSSULTS",response.results)
            })

    }

    render() {

        const showIndicator = this.state.isLoading == true ? <ActivityIndicator size="large" color="#0000ff" /> : null;
        return(
            <View style={GlobalStyles.container}>
                <SearchBarComponent style={GlobalStyles.searchBar}/>
                <PokeBanner/>
                <View style={GlobalStyles.activityIndicator}>{showIndicator}</View>
                <View style={GlobalStyles.pokeFlatList}>
                <FlatList
                    contentContainerStyle={{flexDirection: "row",justifyContent:"center", alignItems:"center"}}
                    keyExtractor={(item, index) => item.name}
                    numColumns={3}
                    data={this.state.dataSource} 
                    renderItem={({item})=> 
                    <View style={{flex: 1, flexDirection: "column", margin: 1}}>
                    <TouchableOpacity onPress={()=> this.props.navigation.navigate('PokeDetails', 
                    {item ,imageUrl: `https://projectpokemon.org/images/normal-sprite/${item.name}.gif`})}>
                        <PokeDetails imageUrl={`https://projectpokemon.org/images/normal-sprite/${item.name}.gif`} name={item.name}/>
                    </TouchableOpacity>
                    </View>
                    }/>
                </View>
                <Button onPress={()=> this.props.navigation.navigate("About")} title="Go to about"/>
            </View>
        )
    }
}


export default Home;

这就是当我尝试使用下面的代码添加 contentContainerStyle 时发生的情况

import React, { useState } from "react";
import { View, Text , Button, FlatList, ActivityIndicator, TouchableOpacity } from "react-native";
import { GlobalStyles } from "../styles/GlobalStyles";
import PokeDetails from "./PokeDetails";
import SearchBarComponent from "../components/SearchBar";
import PokeBanner from "../components/PokeBanner";

class Home extends React.Component {

    constructor(props) {
        super(props);
        this.state = {
            isLoading: true,
            dataSource: [],
        }
    }

    componentDidMount() {
        fetch(`https://pokeapi.co/api/v2/pokemon/?limit=27`)
            .then((res)=> res.json())
            .then((response)=> {
                this.setState({
                    isLoading: false,
                    dataSource: response.results,
                })
                console.log("RESPONSE",response)
                console.log("RESPONSE.RESSSULTS",response.results)
            })

    }

    render() {

        const showIndicator = this.state.isLoading == true ? <ActivityIndicator size="large" color="#0000ff" /> : null;
        return(
            <View style={GlobalStyles.container}>
                <SearchBarComponent style={GlobalStyles.searchBar}/>
                <PokeBanner/>
                <View style={GlobalStyles.activityIndicator}>{showIndicator}</View>
                <View style={GlobalStyles.pokeFlatList}>
                <FlatList
                    contentContainerStyle={{justifyContent:"center", alignItems:"center"}}
                    keyExtractor={(item, index) => item.name}
                    numColumns={3}
                    data={this.state.dataSource} 
                    renderItem={({item})=> 
                    <View style={{flex: 1, flexDirection: "column", margin: 1}}>
                    <TouchableOpacity onPress={()=> this.props.navigation.navigate('PokeDetails', 
                    {item ,imageUrl: `https://projectpokemon.org/images/normal-sprite/${item.name}.gif`})}>
                        <PokeDetails imageUrl={`https://projectpokemon.org/images/normal-sprite/${item.name}.gif`} name={item.name}/>
                    </TouchableOpacity>
                    </View>
                    }/>
                </View>
                <Button onPress={()=> this.props.navigation.navigate("About")} title="Go to about"/>
            </View>
        )
    }
}


export default Home;

Answer 1

为此，您可以使用 FlatList columnWrapperStyle 并从视图中删除 flex:1

改变：

                    <FlatList
                    contentContainerStyle={{justifyContent:"center", alignItems:"center"}}
                    keyExtractor={(item, index) => item.name}
                    numColumns={3}
                    data={this.state.dataSource} 
                    renderItem={({item})=> 
                    <View style={{flex: 1, flexDirection: "column", margin: 1}}>
                    <TouchableOpacity onPress={()=> this.props.navigation.navigate('PokeDetails', 
                    {item ,imageUrl: `https://projectpokemon.org/images/normal-sprite/${item.name}.gif`})}>
                        <PokeDetails imageUrl={`https://projectpokemon.org/images/normal-sprite/${item.name}.gif`} name={item.name}/>
                    </TouchableOpacity>
                    </View>
                    }/>

到

                    <FlatList 
                    columnWrapperStyle={{  flex: 1,justifyContent: "space-around"}}
                    keyExtractor={(item, index) => item.name}
                    numColumns={3}
                    data={this.state.dataSource} 
                    renderItem={({item})=> 
                    <View style={{ flexDirection: "column", margin: 1}}>
                    <TouchableOpacity onPress={()=> this.props.navigation.navigate('PokeDetails', 
                    {item ,imageUrl: `https://projectpokemon.org/images/normal-sprite/${item.name}.gif`})}>
                        <PokeDetails imageUrl={`https://projectpokemon.org/images/normal-sprite/${item.name}.gif`} name={item.name}/>
                    </TouchableOpacity>
                    </View>
                    }/>

希望这可以帮助！