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javascript - React Native - navigation issue "undefined is not an object (this.props.navigation.navigate)"

Im following this tutorial https://reactnavigation.org/docs/intro/ and im running into a bit of issues.

Im using the Expo Client app to render my app every time and not a simulator/emulator.

my code is seen down below.

I originally had the "SimpleApp" const defined above "ChatScreen" component but that gave me the following error:

Route 'Chat' should declare a screen. For example: ...etc

so I moved the decleration of SimpleApp to just above "AppRegistry" and that flagged a new error

Element type is invalid: expected string.....You likely forgot to export your component..etc

the tutorial did not add the key words "export default" to any component which I think it may have to do with the fact that im running it on the Expo app? so I added "export default" to "HomeScreen" and the error went away.

The new error that I cant seem to get rid off(based on the code below) is the following:

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

I can't get rid of it unless I remove the "{}" around "const {navigate}" but that will break the navigation when I press on the button from the home screen

import React from 'react';
import {AppRegistry,Text,Button} from 'react-native';
import { StackNavigator } from 'react-navigation';

export default class HomeScreen extends React.Component {
  static navigationOptions = {
    title: 'Welcome',
  };
  render() {
    const { navigate } = this.props.navigation;
    return (
      <View>
        <Text>Hello, Chat App!</Text>
        <Button
          onPress={() => navigate('Chat')}
          title="Chat with Lucy"
        />
      </View>
    );
  }
}



class ChatScreen extends React.Component {
  static navigationOptions = {
    title: 'Chat with Lucy',
  };
  render() {
    return (
      <View>
        <Text>Chat with Lucy</Text>
      </View>
    );
  }
}

const SimpleApp = StackNavigator({
  Home: { screen: HomeScreen },
  Chat: { screen: ChatScreen },
});
AppRegistry.registerComponent('SimpleApp', () => SimpleApp);
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Additional Info: When you are nesting child components, you need to pass navigation as prop in parent component. //parent.js <childcomponent navigation={this.props.navigation}/>

And you can access navigation like this

//child.js

enter image description here this.props.navigation.navigate('yourcomponent');

Reference: https://reactnavigation.org/docs/en/connecting-navigation-prop.html


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