在类型上生成单元密钥不匹配的平面列表

Question

我有以下应用程序，在我的平面列表上收到一条奇怪的错误消息：

Warning: Failed child context type: Invalid child context `virtualizedCell.cellKey` of 
type `number` supplied to `CellRenderer`, expected `string`.

import React from 'react';
import { StyleSheet, Text, ScrollView, FlatList, View, Button, SegmentedControlIOS } from 'react-native';
import contacts from './contacts';
import {Constants} from 'expo';
console.log(contacts)
const Row=(props)=>(
<View style={styles.row}>
<Text >{props.name}</Text>
<Text >{props.phone}</Text>
</View>
)
export default class App extends React.Component {
state={show: false,selectedIndex: 0}
toggleContacts=()=>{
this.setState({show:!this.state.show})
}
renderItem=(obj)=>{  
console.log(obj)
return <Row {...obj.item} />
}
render() {
// console.log(this.state)
return (
<View style={styles.container}>
<Button title="toggle names" onPress={this.toggleContacts}  />
<SegmentedControlIOS
values={['ScrollView', 'FlatList','SectionList']}
selectedIndex={this.state.selectedIndex}
onChange={(event) => {
this.setState({selectedIndex: event.nativeEvent.selectedSegmentIndex});
}} />
{this.state.show && this.state.selectedIndex === 0 &&
<ScrollView >
{contacts.map(contact=>(
<Row  {...contact}/> ))}
</ScrollView>}
{this.state.show && this.state.selectedIndex === 1 &&
<FlatList
renderItem={obj => (this.renderItem(obj))}
data={contacts}
/>}
</View>
)
}
}
const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: '#fff',
// alignItems: 'flex-start',
paddingTop: Constants.statusBarHeight + 25,
},
row: {
padding:20,
},
});

contacts.js
const NUM_CONTACTS = 10
const firstNames = ['Emma','Noah','Olivia','Liam','Ava','William','Sophia','Mason','Isabella','James','Mia','Benjamin','Charlotte','Jacob','Abigail','Michael','Emily','Elijah','Harper','Ethan','Amelia','Alexander','Evelyn','Oliver','Elizabeth','Daniel','Sofia','Lucas','Madison','Matthew','Avery','Aiden','Ella','Jackson','Scarlett','Logan','Grace','David','Chloe','Joseph','Victoria','Samuel','Riley','Henry','Aria','Owen','Lily','Sebastian','Aubrey','Gabriel','Zoey','Carter','Penelope','Jayden','Lillian','John','Addison','Luke','Layla','Anthony','Natalie','Isaac','Camila','Dylan','Hannah','Wyatt','Brooklyn','Andrew','Zoe','Joshua','Nora','Christopher','Leah','Grayson','Savannah','Jack','Audrey','Julian','Claire','Ryan','Eleanor','Jaxon','Skylar','Levi','Ellie','Nathan','Samantha','Caleb','Stella','Hunter','Paisley','Christian','Violet','Isaiah','Mila','Thomas','Allison','Aaron','Alexa','Lincoln']
const lastNames = ['Smith','Jones','Brown','Johnson','Williams','Miller','Taylor','Wilson','Davis','White','Clark','Hall','Thomas','Thompson','Moore','Hill','Walker','Anderson','Wright','Martin','Wood','Allen','Robinson','Lewis','Scott','Young','Jackson','Adams','Tryniski','Green','Evans','King','Baker','John','Harris','Roberts','Campbell','James','Stewart','Lee','County','Turner','Parker','Cook','Mc','Edwards','Morris','Mitchell','Bell','Ward','Watson','Morgan','Davies','Cooper','Phillips','Rogers','Gray','Hughes','Harrison','Carter','Murphy']
// generate a random number between min and max
const rand = (max, min = 0) => Math.floor(Math.random() * (max - min + 1)) + min
// generate a name
const generateName = () => `${firstNames[rand(firstNames.length - 1)]} ${lastNames[rand(lastNames.length - 1)]}`
// generate a phone number
const generatePhoneNumber = () => `${rand(999, 100)}-${rand(999, 100)}-${rand(9999, 1000)}`
// create a person
const createContact = () => ({name: generateName(), phone: generatePhoneNumber()})
// compare two contacts for alphabetizing
export const compareNames = (contact1, contact2) => contact1.name > contact2.name
// add keys to based on index
const addKeys = (val, key) => ({key, ...val})
// create an array of length NUM_CONTACTS and alphabetize by name
export default Array.from({length: NUM_CONTACTS}, createContact).map(addKeys)

Answer 1

表示 react-native@0.55

在平面列表中添加：

keyExtractor = { (item, index) => index.toString() }