我正在尝试实现一个逻辑来显示从简单的 REST API 获取的一些数据。所以我在 RanjoorExplore 类中获取 JSON 对象，并将数据发送到 data 到另一个类中的 ExploreCard。所以 this.props.data 必须引用传递的变量。通过映射该变量，我在一个简单的 Text 组件中显示响应对象的 title 属性。 我遇到了这个错误:
undefined is not a function(evaluating this.props.data.map).
兰乔探索:
import React, { Component } from 'react';
import {
StyleSheet,
Text,
View,
Image,
ScrollView,
Alert
} from 'react-native';
import Icon from 'react-native-vector-icons/FontAwesome';
import ExploreCard from '../../elements/cards/ExploreCard';
import ExploreHeader from '../../elements/headers/ExploreHeader';
class RanjoorExplore extends Component {
constructor(){
super();
this.state = {
rawData: []
}
}
static navigationOptions = {
header: null,
title: 'Explore',
tabBarIcon: ({ tintColor, focused }) => (
<Icon
name="bandcamp"
size={24}
color={focused ? '#4ab367' : 'white'}
/>
),
headerStyle: { backgroundColor: '#202026' },
headerTitleStyle: {
color: 'white'
}
};
fetchGanjoorData() {
return fetch('https://jsonplaceholder.typicode.com/posts/1')
.then((response) => response.json())
.then((responseJson) => {
this.setState({rawData: responseJson})
})
.catch((error) => {
console.error(error);
});
}
componentDidMount() {
this.fetchGanjoorData();
}
render() {
return (
<View style={styles.ExploreContainer}>
<ExploreHeader />
<ScrollView>
<ExploreCard data={this.state.rawData} />
</ScrollView>
</View>
);
}
}
var styles = StyleSheet.create({
ExploreContainer: {
backgroundColor: '#303036',
height: '100%',
width: '100%'
},
})
export default RanjoorExplore
探索卡:
import React, { Component } from 'react';
import {
StyleSheet,
Text,
View,
Image,
Alert
} from 'react-native';
import { Card, ListItem, Button, Icon, Avatar } from 'react-native-elements';
export default class ExploreCard extends Component {
render() {
/* Mapped data will be processed right here */
let mappedData = this.props.data.map(function (data1) {
return (
<View>
{data1.title}
</View>
)
})
return (
<View style={{ flexDirection: 'row' }}>
<View style={{ flex: 1 }}></View>
<Card
containerStyle={{
width: '85%', height: 250, backgroundColor: '#202026', shadowOpacity: 0.7,
shadowOffset: { height: 5 }, shadowColor: 'black', borderWidth: 0, borderRadius: 8, flexDirection: 'row'
}}
wrapperStyle={{ alignSelf: 'flex-end' }} >
<View style={{ flex: 2, alignSelf: 'flex-end' }}>
<View style={{ flexDirection: 'row', alignSelf: 'flex-end' }}>
<Text style={{ fontFamily: 'IRANSans', marginRight: 5, marginTop: 12, color: '#505056' }}>حافظ</Text>
<Avatar
medium
rounded
source={require('../../img/avatars/ferdowsi.jpg')}
containerStyle={{
alignSelf: 'flex-end', marginRight: 15,
shadowOpacity: 0.7,
shadowOffset: { height: 5 }, shadowColor: 'black'
}}
/>
</View>
<View>
<Text style={{ alignSelf: 'flex-end', fontFamily: 'IRANSans', color: 'white', marginTop: '10%', marginRight: '5%' }}>
{mappedData}
</Text>
<Text style={{ alignSelf: 'flex-start', fontFamily: 'IRANSans', color: 'white' }}>
تا دمی برآساییم زین حجاب ظلمانی
</Text>
</View>
</View>
<View style={{ alignSelf: 'flex-end', backgroundColor: 'transparent', flexDirection: 'row' }}>
<Icon
name='favorite' size={24} color="#34343a" style={{ marginLeft: 5 }}
/>
<Icon
name='grade' size={24} color="#34343a" style={{ marginLeft: 5 }}
/>
<View>
<Button
textStyle={{ fontSize: 15 }}
iconRight
backgroundColor='#4ab367'
fontFamily='IRANSans_UltraLight'
buttonStyle={{
height: 15, width: 110,
borderRadius: 8
}}
title='ادامه مطلب'
/>
</View>
</View>
</Card>
<View style={{ flex: 1 }}></View>
</View>
);
}
}
有人可以帮我解决这个问题吗？ 提前致谢。
最佳答案
https://jsonplaceholder.typicode.com/posts/1 返回一个对象，而不是数组。因此，map 不是一个有效的操作
也许您打算使用 https://jsonplaceholder.typicode.com/posts/？返回一个数组
关于android - React Native : Undefined is not a function(evaluating this. Prop ...)，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/45108668/