block9.js

// App.js
import React from 'react';
import { Text, View } from 'react-native';
import { createBottomTabNavigator } from 'react-navigation';

class HomeScreen extends React.Component {
	render() {
		return (
			<View style={{ flex: 1, justifyContent: 'center', alignItems: 'center' }}>
				<Text>Home!</Text>
			</View>
		);
	}
}

class SettingsScreen extends React.Component {
	render() {
		return (
			<View style={{ flex: 1, justifyContent: 'center', alignItems: 'center' }}>
				<Text>Settings!</Text>
			</View>
		);
	}
}

export default createBottomTabNavigator({
	Home: HomeScreen,
	Settings: SettingsScreen
});