如何解决React Native的警告信息

我现在正在学习React Native，最近我收到了下面的日志消息 .

警告：不推荐使用componentWillMount，将在下一个主要版本中删除 . 请改用componentDidMount . 作为临时解决方法，您可以重命名为UNSAFE_componentWillMount .

我正在做这个教程"React Native Tutorial: Building Android Apps with JavaScript" https://www.raywenderlich.com/178012/react-native-tutorial-building-android-apps-javascript

我该怎么做才能删除邮件？

我安装了react-native-cli并做了react-native init projectName . 我改变了package.json . 我改变了“react”：“^ 16.3.0-alpha.1”到“^ 16.2.0”然后我做了npm install .

我的package.json

{“name”：“PropertyFinder”，“version”：“0.0.1”，“private”：true，“scripts”：{“start”：“node node_modules / react-native / local-cli / cli.js start“，”test“：”jest“}，”dependencies“：{”react“：”^ 16.2.0“，”react-native“：”0.54.0“，”react-navigation“：”^ 1.3 . 0“}，”devDependencies“：{”babel-jest“：”22.4.1“，”babel-preset-react-native“：”4.0.0“，”jest“：”22.4.2“，”反应 - test-renderer“：”^ 16.2.0“}，”jest“：{”preset“：”react-native“}}

但仍然显示出警告 .

SearchPage.js

'use strict';

import React, { Component } from 'react';
import {
  StyleSheet,
  Text,
  TextInput,
  View,
  Button,
  ActivityIndicator,
  Image
} from 'react-native';
// import { StackNavigator } from 'react-navigation';

export default class SearchPage extends Component<{}> {
  static navigationOptions = {
    title: 'Property Finder',
  };

  constructor(props) {
    super(props);
    this.state = {
      searchString: 'london'
    };
  }

  _onSearchTextChanged = (event) => {
    console.log('_onSearchTextChanged');
    this.setState({
      searchString: event.nativeEvent.text
    });
    console.log('Current: ' + this.state.searchString + ', Next: ' + event.nativeEvent.text);
  }

  render() {
    console.log('SearchPage render');

    return (
      <View style={styles.container}>
        <Text style={styles.description}>
          Search for houses to buy!
        </Text>      
        <Text style={styles.description}>
          Search by place-name or postcode.
        </Text>
        <View style={styles.flowRight}>
          <TextInput
            underlineColorAndroid={'transparent'}
            style={styles.searchInput}
            value={this.state.searchString}
            onChange={this._onSearchTextChanged}
            placeholder='Search via name or postcode' />
          <Button
            onPress={() => {}}
            color='#48bbec'
            title='Go'
          />
        </View>
        <Image source={require('./Resources/house.png')} style={styles.image} />
      </View>    
    );
  }
}

const styles = StyleSheet.create({
  description: {
    fontSize: 18,
    textAlign: 'center',
    color: '#656565',
    marginBottom: 20,
  },
  container: {
    padding: 30,
    marginTop: 65,
    alignItems: 'center',
  },
  welcome: {
    fontSize: 20,
    textAlign: 'center',
    margin: 10,
  },
  instructions: {
    textAlign: 'center',
    color: '#333333',
    marginBottom: 5,
  },
  flowRight: {
    flexDirection: 'row',
    alignItems: 'center',
    alignSelf: 'stretch',
  },
  searchInput: {
    height: 36,
    padding: 4,
    marginRight: 5,
    flexGrow: 1,
    fontSize: 18,
    borderWidth: 1,
    borderColor: '#48bbec',
    borderRadius: 8,
    color: '#48bbec',
  },
  image: {
    width: 217,
    height: 138,
  },
});

App.js

'use strict';
/**
 * Sample React Native App
 * https://github.com/facebook/react-native
 * @flow
 */

import React, { Component } from 'react';
import {
  Platform,
  StyleSheet,
  Text,
  View
} from 'react-native';
import { StackNavigator } from 'react-navigation';

import SearchPage from './SearchPage';

// type Props = {};


const App = StackNavigator({
  Home: {
    screen: SearchPage,
  },
});
export default App;

对不起，我的英语不好 .