undefined 不是 object（评估 '_this2.props.navigation.navigate'）

Question

单击 header 时，我希望它导航到下一页。但是，我不知道如何访问 class 之外的导航道具。关于如何做到这一点有什么建议吗？

import React,{Component} from 'react'
import { View, Text, TouchableOpacity, FlatList} from 'react-native'

class header extends Component {
  render(){
    return(
        <TouchableOpacity
          onPress={() => **this.props.navigation.navigate('PageTwo')**}
        >
          <Text>{'Go to next Page Two'}</Text>
        </TouchableOpacity>
    )
  }
}

export default class PageOne extends Component {
  static navigationOptions = {
    title: 'Page One',
  }
  constructor(props) {
    super(props);
    this.state = {
      data: // ...
    };
  }

  _renderItem = ({item}) => (
    // ...
  );

  render(){
    return(
        <FlatList
          ListHeaderComponent={header}
          data={this.state.data}
          renderItem={this._renderItem}
        />
    )
  }
}

Answer 1

我假设是 React Navigation？

使用 withNavigation HOC (https://github.com/react-community/react-navigation/blob/aead8ff9fbd2aceb2d06c8049c8ad0d55d77b5ab/docs/api/withNavigation.md)

Answer 2

对于 React 导航首先确保您在项目中安装了 react-navigation lib。如果不是，则在 cmd 中运行 "npm install --save react-navigation"。然后创建一个 App.js 文件来保存所有路由器名称，如

App.js :

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

import Splash from './src/components/Splash/Splash'
import Login from './src/components/Splash/Login'

const Navigation = StackNavigator({
  Splash : {
    screen : Splash
  },
  Login : {
    screen : Login
  },
})
export default Navigation;

在我的例子中，src 是用于存储所有 js 文件的脏文件。

现在在 index.android.js 中设置 AppRegistry.registerComponent。

index.android.js

import React, { Component } from 'react';
import {
  AppRegistry,
  Text,
  View
} from 'react-native';
import {StackNavigator} from 'react-navigation';
import Splash from './src/components/Splash/Splash'
import Navigation from './App'
export class FirstReactDemo extends Component {
  render() {
    return (
      <Splash/>
    );
  }
}
AppRegistry.registerComponent('FirstReactDemo', () => Navigation);

现在，在首屏设置onclick监听器。

Splash.js

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

export default class SplashScreen extends Component {



static navigationOptions = {
      title: 'Splash',
    };
  render() {
    const { navigate } = this.props.navigation;
    return (
      <View>
        <Text
          onPress={() =>navigate('Login')}
          style={styles.text}>My Splash screen</Text>
      </View>
    );
  }
}

为下一个屏幕创建 Login.js 文件。

Answer 3

在使用您的子组件时自己传递 navigation = {navigation}。

undefined 不是 object（评估 '_this2.props.navigation.navigate'）

undefined is not an object (evaluating '_this2.props.navigation.navigate')

react-native

react-navigation