问题
I am doing doing navigation with new react native navigation all I want is when button is pressed it navigate to next screen, I have followed new documentation but the problem is I am doing with classes and in the documentation all the work is done with functions in App.js, I tried to modify my code accordingly but couldn't do with classes as onPress button it does not navigate instead gives me error. This is my app.js:
import * as React from 'react';
import { Button, View, Text } from 'react-native';
import { NavigationContainer,useNavigation } from '@react-navigation/native';
import { createStackNavigator } from '@react-navigation/stack';
import Nav from './screens/Nav';
import Home from './screens/Home';
import Login from './screens/Login';
const Stack = createStackNavigator();
export default class App extends React.Component {
render(){
return (
<NavigationContainer>
<Stack.Navigator headerMode='none' initialRouteName="Nav">
<Stack.Screen name="Splash" component={Nav} />
<Stack.Screen name="Home" component={Home} />
<Stack.Screen name="Login" component={Login} />
</Stack.Navigator>
</NavigationContainer>
);
}
}
That is my Home.js from where when it clicks Login button it moves to next screen which is Login.js:
import React, { Component } from 'react';
import {StyleSheet, Text, View, TouchableHighlight,Image,BackHandler} from 'react-native';
import Login from './Login';
export default class Home extends Component {
render() {
const { navigation } = this.props;
return (
<View style={styles.container}>
<TouchableHighlight style={styles.buttonContainer} onPress={() => navigation.navigate('Login')}>
<Text style={styles.loginText}>Login</Text>
</TouchableHighlight>
</View>
);
}
}
That is my Login.js Screen:
import React, { Component } from 'react';
import {StyleSheet, Text, View,TextInput,TouchableHighlight, Image} from 'react-native';
export default class Login extends Component {
constructor(props) {
super(props);
this.state = {
email : '',
password: '',
}
}
render() {
return (
<View style={styles.container}>
<Image source={require('../assets/logo.png')}
style={{ width: 250, height: 250, marginHorizontal: 20 }}
resizeMode="contain"/>
<Text style = {styles.text}>UniQmove Training </Text>
<View style={styles.inputContainer}>
<Image style={styles.inputIcon} source={{uri: 'https://img.icons8.com/ultraviolet/40/000000/email.png'}}/>
<TextInput style={styles.inputs}
placeholder="Email"
keyboardType="email-address"
underlineColorAndroid='transparent'
onChangeText={(email) => this.setState({email})}/>
</View>
<View style={styles.inputContainer}>
<Image style={styles.inputIcon} source={{uri: 'https://img.icons8.com/ultraviolet/40/000000/password.png'}}/>
<TextInput style={styles.inputs}
placeholder="Password"
secureTextEntry={true}
underlineColorAndroid='transparent'
onChangeText={(password) => this.setState({password})}/>
</View>
<TouchableHighlight style={[styles.buttonContainer, styles.loginButton]} onPress={() => {this.loginRoles();this.handleLogin();}}>
<Text style={styles.loginText}>Login</Text>
</TouchableHighlight>
</View>
);
}
}
The problem is when I import Login.js in Home it is not using it in navigation.navigate('Login')
My package.jason:
{
"name": "UniQmoves",
"version": "0.0.1",
"private": true,
"scripts": {
"android": "react-native run-android",
"ios": "react-native run-ios",
"start": "react-native start",
"test": "jest",
"lint": "eslint ."
},
"dependencies": {
"@react-native-community/masked-view": "^0.1.7",
"@react-navigation/native": "^5.0.9",
"@react-navigation/stack": "^5.1.1",
"react": "16.9.0",
"react-native": "0.61.5",
"react-native-gesture-handler": "^1.6.0",
"react-native-reanimated": "^1.7.0",
"react-native-safe-area-context": "^0.7.3",
"react-native-screens": "^2.3.0"
},
"devDependencies": {
"@babel/core": "7.8.7",
"@babel/runtime": "7.8.7",
"@react-native-community/eslint-config": "0.0.5",
"babel-jest": "24.9.0",
"eslint": "6.8.0",
"jest": "24.9.0",
"metro-react-native-babel-preset": "0.56.4",
"react-test-renderer": "16.9.0"
},
"jest": {
"preset": "react-native"
}
}
回答1:
there is a little change in code and your code will work fine
in App Class initialRouteName and screen name should same change Splash to Nav
<Stack.Navigator headerMode='none' initialRouteName="Nav">
<Stack.Screen name="Splash" component={Nav} />
in Home class update after use this line
import React, { Component } from 'react';
import {StyleSheet, Text, View, TouchableHighlight,Image,BackHandler} from 'react-native';
import Login from './Login';
export default class Home extends Component {
render() {
return (
<View style={styles.container}>
//<TouchableHighlight style={styles.buttonContainer} onPress={() => navigation.navigate('Login')}>
use this
<TouchableHighlight style={styles.buttonContainer} onPress={() => this.props.navigation.navigate('Login')}>
<Text style={styles.loginText}>Login</Text>
</TouchableHighlight>
</View>
);
}
}
来源:https://stackoverflow.com/questions/60668530/undefined-is-not-an-object-navigation-navigate-react-native-navigation-5-new