FlatList在类型上生成cellkey不匹配

Question

我有以下应用程序，并且在我的FlatList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

for react-native@0.55

在Flatlist中添加：

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