/**
 * Created by YiBing on 2017/5/4.
 * Introducing Stack Navigator:
 * The title of the HomeScreen is configurable on the static navigationOptions,* where many options can be set to configure the presentation of the screen in the 

navigator.
 */

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

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',{user: 'yb'})} //Passing params
                    title="Chat with Lucy"
                />
            </View>
        );
    }
}

class ChatScreen extends React.Component {
    // Nav options can be defined as a function of the screen's props:
    static navigationOptions = ({ navigation }) => ({
        title: `Chat with ${navigation.state.params.user}`,});
    render() {
        // The screen's current route is passed in to `props.navigation.state`:
        const { params } = this.props.navigation.state;
        return (
            <View>
                <Text>Chat with {params.user}</Text>
            </View>
        );
    }
}

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

AppRegistry.registerComponent('SimpleAppReactNavigation',() => 

SimpleAppReactNavigation);