react-navigation push and pop

gistfile1.txt

//    "react-native": "0.42.0",
//    "react-navigation": "^1.0.0-beta.7"
    
    
 /**
 * Sample React Native App
 * https://github.com/facebook/react-native
 * @flow
 */

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


import { StackNavigator, TabNavigator } from 'react-navigation';

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


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>
    );
  }
}




const SimpleApp = StackNavigator({
  Home: { screen: HomeScreen },
  Chat: { screen: ChatScreen },
});

AppRegistry.registerComponent('TestReactNavigation', () => SimpleApp);