This is the third blog in a multipart series where we will be building Chatty, a WhatsApp clone, using React Native and Apollo.
Here’s what we will accomplish in this tutorial:
- Create the basic layout for our React Native application
- Build GraphQL Queries using
react-apollo
First we’re going to need a few packages:
# make sure to add these packages to client folder!!!
cd client
npm i lodash moment graphql-tag prop-types randomcolor react-navigationlodashis a top notch utility library for dealing with data in JSmomentis the goto package for dealing with Dates in JSgraphql-taglets us parse GraphQL Queries from stringsprop-typesis a runtime type checker for React props and similar objectsrandomcolorwill let us generate random colorsreact-navigationis a collaboration between people from Facebook, Exponent and the React community to create the best navigation solution for the React ecosystem
I’m a visual guy, so I like to first establish the general look and feel of the app before adding data.
Using react-navigation, we can design routing for our application based on Screens. A Screen is essentially a full screen or collection of sub-screens within our application. It’s easiest to understand with a basic example.
Let’s create a new file client/src/navigation.js where we will declare the navigation for our application:
@@ -15,9 +15,15 @@
┊15┊15┊ "apollo-link-redux": "^0.2.1",
┊16┊16┊ "graphql": "^0.12.3",
┊17┊17┊ "graphql-tag": "^2.4.2",
+┊ ┊18┊ "lodash": "^4.17.5",
+┊ ┊19┊ "moment": "^2.20.1",
+┊ ┊20┊ "prop-types": "^15.6.0",
+┊ ┊21┊ "randomcolor": "^0.5.3",
┊18┊22┊ "react": "16.4.1",
┊19┊23┊ "react-apollo": "^2.0.4",
┊20┊24┊ "react-native": "0.56.0",
+┊ ┊25┊ "react-navigation": "^1.0.3",
+┊ ┊26┊ "react-navigation-redux-helpers": "^1.1.2",
┊21┊27┊ "react-redux": "^5.0.5",
┊22┊28┊ "redux": "^3.7.2",
┊23┊29┊ "redux-devtools-extension": "^2.13.2"@@ -0,0 +1,88 @@
+┊ ┊ 1┊import PropTypes from 'prop-types';
+┊ ┊ 2┊import React, { Component } from 'react';
+┊ ┊ 3┊import { NavigationActions, addNavigationHelpers, StackNavigator, TabNavigator } from 'react-navigation';
+┊ ┊ 4┊import {
+┊ ┊ 5┊ createReduxBoundAddListener,
+┊ ┊ 6┊ createReactNavigationReduxMiddleware,
+┊ ┊ 7┊} from 'react-navigation-redux-helpers';
+┊ ┊ 8┊import { Text, View, StyleSheet } from 'react-native';
+┊ ┊ 9┊import { connect } from 'react-redux';
+┊ ┊10┊
+┊ ┊11┊const styles = StyleSheet.create({
+┊ ┊12┊ container: {
+┊ ┊13┊ flex: 1,
+┊ ┊14┊ justifyContent: 'center',
+┊ ┊15┊ alignItems: 'center',
+┊ ┊16┊ backgroundColor: 'white',
+┊ ┊17┊ },
+┊ ┊18┊ tabText: {
+┊ ┊19┊ color: '#777',
+┊ ┊20┊ fontSize: 10,
+┊ ┊21┊ justifyContent: 'center',
+┊ ┊22┊ },
+┊ ┊23┊ selected: {
+┊ ┊24┊ color: 'blue',
+┊ ┊25┊ },
+┊ ┊26┊});
+┊ ┊27┊
+┊ ┊28┊const TestScreen = title => () => (
+┊ ┊29┊ <View style={styles.container}>
+┊ ┊30┊ <Text>
+┊ ┊31┊ {title}
+┊ ┊32┊ </Text>
+┊ ┊33┊ </View>
+┊ ┊34┊);
+┊ ┊35┊
+┊ ┊36┊// tabs in main screen
+┊ ┊37┊const MainScreenNavigator = TabNavigator({
+┊ ┊38┊ Chats: { screen: TestScreen('Chats') },
+┊ ┊39┊ Settings: { screen: TestScreen('Settings') },
+┊ ┊40┊}, {
+┊ ┊41┊ initialRouteName: 'Chats',
+┊ ┊42┊});
+┊ ┊43┊
+┊ ┊44┊const AppNavigator = StackNavigator({
+┊ ┊45┊ Main: { screen: MainScreenNavigator },
+┊ ┊46┊});
+┊ ┊47┊
+┊ ┊48┊// reducer initialization code
+┊ ┊49┊const initialState=AppNavigator.router.getStateForAction(NavigationActions.reset({
+┊ ┊50┊ index: 0,
+┊ ┊51┊ actions: [
+┊ ┊52┊ NavigationActions.navigate({
+┊ ┊53┊ routeName: 'Main',
+┊ ┊54┊ }),
+┊ ┊55┊ ],
+┊ ┊56┊}));
+┊ ┊57┊
+┊ ┊58┊export const navigationReducer = (state = initialState, action) => {
+┊ ┊59┊ const nextState = AppNavigator.router.getStateForAction(action, state);
+┊ ┊60┊
+┊ ┊61┊ // Simply return the original `state` if `nextState` is null or undefined.
+┊ ┊62┊ return nextState || state;
+┊ ┊63┊};
+┊ ┊64┊
+┊ ┊65┊// Note: createReactNavigationReduxMiddleware must be run before createReduxBoundAddListener
+┊ ┊66┊export const navigationMiddleware = createReactNavigationReduxMiddleware(
+┊ ┊67┊ "root",
+┊ ┊68┊ state => state.nav,
+┊ ┊69┊);
+┊ ┊70┊const addListener = createReduxBoundAddListener("root");
+┊ ┊71┊
+┊ ┊72┊class AppWithNavigationState extends Component {
+┊ ┊73┊ render() {
+┊ ┊74┊ return (
+┊ ┊75┊ <AppNavigator navigation={addNavigationHelpers({
+┊ ┊76┊ dispatch: this.props.dispatch,
+┊ ┊77┊ state: this.props.nav,
+┊ ┊78┊ addListener,
+┊ ┊79┊ })} />
+┊ ┊80┊ );
+┊ ┊81┊ }
+┊ ┊82┊}
+┊ ┊83┊
+┊ ┊84┊const mapStateToProps = state => ({
+┊ ┊85┊ nav: state.nav,
+┊ ┊86┊});
+┊ ┊87┊
+┊ ┊88┊export default connect(mapStateToProps)(AppWithNavigationState);This setup will create a StackNavigator named AppNavigator that will hold all our Screens. A StackNavigator stacks Screens on top of each other like pancakes when we navigate to them.
Within AppNavigator, we can add different Screens and other Navigators that can be pushed onto the stack.
MainScreenNavigator is a TabNavigator, which means it organizes Screens in tabs. The Screens within MainScreenNavigator are just placeholders which display the title of the Screen for now. MainScreenNavigator will be our default view, so we've added it as the first Screen in AppNavigator.
We also have created a basic reducer for our navigator (navigatorReducer) to track navigation actions in Redux. We use connect from react-redux to connect our AppNavigator to Redux.
We can update app.js to use our new Redux connected AppWithNavigationState component and combine navigationReducer with our apollo reducer:
@@ -1,30 +1,32 @@
┊ 1┊ 1┊import React, { Component } from 'react';
-┊ 2┊ ┊import {
-┊ 3┊ ┊ Platform,
-┊ 4┊ ┊ StyleSheet,
-┊ 5┊ ┊ Text,
-┊ 6┊ ┊ View,
-┊ 7┊ ┊} from 'react-native';
┊ 8┊ 2┊
┊ 9┊ 3┊import { ApolloClient } from 'apollo-client';
┊10┊ 4┊import { ApolloLink } from 'apollo-link';
┊11┊ 5┊import { ApolloProvider } from 'react-apollo';
┊12┊ 6┊import { composeWithDevTools } from 'redux-devtools-extension';
┊13┊ 7┊import { createHttpLink } from 'apollo-link-http';
-┊14┊ ┊import { createStore, combineReducers } from 'redux';
+┊ ┊ 8┊import { createStore, combineReducers, applyMiddleware } from 'redux';
┊15┊ 9┊import { Provider } from 'react-redux';
┊16┊10┊import { ReduxCache, apolloReducer } from 'apollo-cache-redux';
┊17┊11┊import ReduxLink from 'apollo-link-redux';
┊18┊12┊import { onError } from 'apollo-link-error';
┊19┊13┊
+┊ ┊14┊import AppWithNavigationState, {
+┊ ┊15┊ navigationReducer,
+┊ ┊16┊ navigationMiddleware,
+┊ ┊17┊} from './navigation';
+┊ ┊18┊
┊20┊19┊const URL = 'localhost:8080'; // set your comp's url here
┊21┊20┊
┊22┊21┊const store = createStore(
┊23┊22┊ combineReducers({
┊24┊23┊ apollo: apolloReducer,
+┊ ┊24┊ nav: navigationReducer,
┊25┊25┊ }),
┊26┊26┊ {}, // initial state
-┊27┊ ┊ composeWithDevTools(),
+┊ ┊27┊ composeWithDevTools(
+┊ ┊28┊ applyMiddleware(navigationMiddleware),
+┊ ┊29┊ ),
┊28┊30┊);
┊29┊31┊
┊30┊32┊const cache = new ReduxCache({ store });@@ -48,44 +50,14 @@
┊48┊50┊ cache,
┊49┊51┊});
┊50┊52┊
-┊51┊ ┊const instructions = Platform.select({
-┊52┊ ┊ ios: 'Press Cmd+R to reload,\n' + 'Cmd+D or shake for dev menu',
-┊53┊ ┊ android:
-┊54┊ ┊ 'Double tap R on your keyboard to reload,\n' +
-┊55┊ ┊ 'Shake or press menu button for dev menu',
-┊56┊ ┊});
-┊57┊ ┊
┊58┊53┊export default class App extends Component {
┊59┊54┊ render() {
┊60┊55┊ return (
┊61┊56┊ <ApolloProvider client={client}>
┊62┊57┊ <Provider store={store}>
-┊63┊ ┊ <View style={styles.container}>
-┊64┊ ┊ <Text style={styles.welcome}>Welcome to React Native!</Text>
-┊65┊ ┊ <Text style={styles.instructions}>To get started, edit App.js</Text>
-┊66┊ ┊ <Text style={styles.instructions}>{instructions}</Text>
-┊67┊ ┊ </View>
+┊ ┊58┊ <AppWithNavigationState />
┊68┊59┊ </Provider>
┊69┊60┊ </ApolloProvider>
┊70┊61┊ );
┊71┊62┊ }
┊72┊63┊}
-┊73┊ ┊
-┊74┊ ┊const styles = StyleSheet.create({
-┊75┊ ┊ container: {
-┊76┊ ┊ flex: 1,
-┊77┊ ┊ justifyContent: 'center',
-┊78┊ ┊ alignItems: 'center',
-┊79┊ ┊ backgroundColor: '#F5FCFF',
-┊80┊ ┊ },
-┊81┊ ┊ welcome: {
-┊82┊ ┊ fontSize: 20,
-┊83┊ ┊ textAlign: 'center',
-┊84┊ ┊ margin: 10,
-┊85┊ ┊ },
-┊86┊ ┊ instructions: {
-┊87┊ ┊ textAlign: 'center',
-┊88┊ ┊ color: '#333333',
-┊89┊ ┊ marginBottom: 5,
-┊90┊ ┊ },
-┊91┊ ┊});Refresh the app to see some simple tabs: 
On the Chats tab, we want to show a list of the user’s groups. We’ll create a Groups screen component in a new file client/src/screens/groups.screen.js:
@@ -0,0 +1,84 @@
+┊ ┊ 1┊import { _ } from 'lodash';
+┊ ┊ 2┊import PropTypes from 'prop-types';
+┊ ┊ 3┊import React, { Component } from 'react';
+┊ ┊ 4┊import {
+┊ ┊ 5┊ FlatList,
+┊ ┊ 6┊ StyleSheet,
+┊ ┊ 7┊ Text,
+┊ ┊ 8┊ TouchableHighlight,
+┊ ┊ 9┊ View,
+┊ ┊10┊} from 'react-native';
+┊ ┊11┊
+┊ ┊12┊const styles = StyleSheet.create({
+┊ ┊13┊ container: {
+┊ ┊14┊ backgroundColor: 'white',
+┊ ┊15┊ flex: 1,
+┊ ┊16┊ },
+┊ ┊17┊ groupContainer: {
+┊ ┊18┊ flex: 1,
+┊ ┊19┊ flexDirection: 'row',
+┊ ┊20┊ alignItems: 'center',
+┊ ┊21┊ backgroundColor: 'white',
+┊ ┊22┊ borderBottomColor: '#eee',
+┊ ┊23┊ borderBottomWidth: 1,
+┊ ┊24┊ paddingHorizontal: 12,
+┊ ┊25┊ paddingVertical: 8,
+┊ ┊26┊ },
+┊ ┊27┊ groupName: {
+┊ ┊28┊ fontWeight: 'bold',
+┊ ┊29┊ flex: 0.7,
+┊ ┊30┊ },
+┊ ┊31┊});
+┊ ┊32┊
+┊ ┊33┊// create fake data to populate our ListView
+┊ ┊34┊const fakeData = () => _.times(100, i => ({
+┊ ┊35┊ id: i,
+┊ ┊36┊ name: `Group ${i}`,
+┊ ┊37┊}));
+┊ ┊38┊
+┊ ┊39┊class Group extends Component {
+┊ ┊40┊ render() {
+┊ ┊41┊ const { id, name } = this.props.group;
+┊ ┊42┊ return (
+┊ ┊43┊ <TouchableHighlight
+┊ ┊44┊ key={id}
+┊ ┊45┊ >
+┊ ┊46┊ <View style={styles.groupContainer}>
+┊ ┊47┊ <Text style={styles.groupName}>{`${name}`}</Text>
+┊ ┊48┊ </View>
+┊ ┊49┊ </TouchableHighlight>
+┊ ┊50┊ );
+┊ ┊51┊ }
+┊ ┊52┊}
+┊ ┊53┊
+┊ ┊54┊Group.propTypes = {
+┊ ┊55┊ group: PropTypes.shape({
+┊ ┊56┊ id: PropTypes.number,
+┊ ┊57┊ name: PropTypes.string,
+┊ ┊58┊ }),
+┊ ┊59┊};
+┊ ┊60┊
+┊ ┊61┊class Groups extends Component {
+┊ ┊62┊ static navigationOptions = {
+┊ ┊63┊ title: 'Chats',
+┊ ┊64┊ };
+┊ ┊65┊
+┊ ┊66┊ keyExtractor = item => item.id.toString();
+┊ ┊67┊
+┊ ┊68┊ renderItem = ({ item }) => <Group group={item} />;
+┊ ┊69┊
+┊ ┊70┊ render() {
+┊ ┊71┊ // render list of groups for user
+┊ ┊72┊ return (
+┊ ┊73┊ <View style={styles.container}>
+┊ ┊74┊ <FlatList
+┊ ┊75┊ data={fakeData()}
+┊ ┊76┊ keyExtractor={this.keyExtractor}
+┊ ┊77┊ renderItem={this.renderItem}
+┊ ┊78┊ />
+┊ ┊79┊ </View>
+┊ ┊80┊ );
+┊ ┊81┊ }
+┊ ┊82┊}
+┊ ┊83┊
+┊ ┊84┊export default Groups;And insert Groups into our AppNavigator:
@@ -8,6 +8,8 @@
┊ 8┊ 8┊import { Text, View, StyleSheet } from 'react-native';
┊ 9┊ 9┊import { connect } from 'react-redux';
┊10┊10┊
+┊ ┊11┊import Groups from './screens/groups.screen';
+┊ ┊12┊
┊11┊13┊const styles = StyleSheet.create({
┊12┊14┊ container: {
┊13┊15┊ flex: 1,@@ -35,7 +37,7 @@
┊35┊37┊
┊36┊38┊// tabs in main screen
┊37┊39┊const MainScreenNavigator = TabNavigator({
-┊38┊ ┊ Chats: { screen: TestScreen('Chats') },
+┊ ┊40┊ Chats: { screen: Groups },
┊39┊41┊ Settings: { screen: TestScreen('Settings') },
┊40┊42┊}, {
┊41┊43┊ initialRouteName: 'Chats',When the user presses one of the rows in our FlatList, we want to push a new Screen with the message thread for the selected group. For this Screen, we’ll create a new Messages component which will hold a list of Message components:
@@ -0,0 +1,70 @@
+┊ ┊ 1┊import { _ } from 'lodash';
+┊ ┊ 2┊import {
+┊ ┊ 3┊ FlatList,
+┊ ┊ 4┊ StyleSheet,
+┊ ┊ 5┊ View,
+┊ ┊ 6┊} from 'react-native';
+┊ ┊ 7┊import PropTypes from 'prop-types';
+┊ ┊ 8┊import React, { Component } from 'react';
+┊ ┊ 9┊import randomColor from 'randomcolor';
+┊ ┊10┊
+┊ ┊11┊import Message from '../components/message.component';
+┊ ┊12┊
+┊ ┊13┊const styles = StyleSheet.create({
+┊ ┊14┊ container: {
+┊ ┊15┊ alignItems: 'stretch',
+┊ ┊16┊ backgroundColor: '#e5ddd5',
+┊ ┊17┊ flex: 1,
+┊ ┊18┊ flexDirection: 'column',
+┊ ┊19┊ },
+┊ ┊20┊});
+┊ ┊21┊
+┊ ┊22┊const fakeData = () => _.times(100, i => ({
+┊ ┊23┊ // every message will have a different color
+┊ ┊24┊ color: randomColor(),
+┊ ┊25┊ // every 5th message will look like it's from the current user
+┊ ┊26┊ isCurrentUser: i % 5 === 0,
+┊ ┊27┊ message: {
+┊ ┊28┊ id: i,
+┊ ┊29┊ createdAt: new Date().toISOString(),
+┊ ┊30┊ from: {
+┊ ┊31┊ username: `Username ${i}`,
+┊ ┊32┊ },
+┊ ┊33┊ text: `Message ${i}`,
+┊ ┊34┊ },
+┊ ┊35┊}));
+┊ ┊36┊
+┊ ┊37┊class Messages extends Component {
+┊ ┊38┊ static navigationOptions = ({ navigation }) => {
+┊ ┊39┊ const { state } = navigation;
+┊ ┊40┊ return {
+┊ ┊41┊ title: state.params.title,
+┊ ┊42┊ };
+┊ ┊43┊ };
+┊ ┊44┊
+┊ ┊45┊ keyExtractor = item => item.message.id.toString();
+┊ ┊46┊
+┊ ┊47┊ renderItem = ({ item: { isCurrentUser, message, color } }) => (
+┊ ┊48┊ <Message
+┊ ┊49┊ color={color}
+┊ ┊50┊ isCurrentUser={isCurrentUser}
+┊ ┊51┊ message={message}
+┊ ┊52┊ />
+┊ ┊53┊ )
+┊ ┊54┊
+┊ ┊55┊ render() {
+┊ ┊56┊ // render list of messages for group
+┊ ┊57┊ return (
+┊ ┊58┊ <View style={styles.container}>
+┊ ┊59┊ <FlatList
+┊ ┊60┊ data={fakeData()}
+┊ ┊61┊ keyExtractor={this.keyExtractor}
+┊ ┊62┊ renderItem={this.renderItem}
+┊ ┊63┊ ListEmptyComponent={<View />}
+┊ ┊64┊ />
+┊ ┊65┊ </View>
+┊ ┊66┊ );
+┊ ┊67┊ }
+┊ ┊68┊}
+┊ ┊69┊
+┊ ┊70┊export default Messages;We’ll also write the code for the individual Message components that populate the FlatList in Messages:
@@ -0,0 +1,85 @@
+┊ ┊ 1┊import moment from 'moment';
+┊ ┊ 2┊import React, { PureComponent } from 'react';
+┊ ┊ 3┊import PropTypes from 'prop-types';
+┊ ┊ 4┊import {
+┊ ┊ 5┊ StyleSheet,
+┊ ┊ 6┊ Text,
+┊ ┊ 7┊ View,
+┊ ┊ 8┊} from 'react-native';
+┊ ┊ 9┊
+┊ ┊10┊const styles = StyleSheet.create({
+┊ ┊11┊ container: {
+┊ ┊12┊ flex: 1,
+┊ ┊13┊ flexDirection: 'row',
+┊ ┊14┊ },
+┊ ┊15┊ message: {
+┊ ┊16┊ flex: 0.8,
+┊ ┊17┊ backgroundColor: 'white',
+┊ ┊18┊ borderRadius: 6,
+┊ ┊19┊ marginHorizontal: 16,
+┊ ┊20┊ marginVertical: 2,
+┊ ┊21┊ paddingHorizontal: 8,
+┊ ┊22┊ paddingVertical: 6,
+┊ ┊23┊ shadowColor: 'black',
+┊ ┊24┊ shadowOpacity: 0.5,
+┊ ┊25┊ shadowRadius: 1,
+┊ ┊26┊ shadowOffset: {
+┊ ┊27┊ height: 1,
+┊ ┊28┊ },
+┊ ┊29┊ },
+┊ ┊30┊ myMessage: {
+┊ ┊31┊ backgroundColor: '#dcf8c6',
+┊ ┊32┊ },
+┊ ┊33┊ messageUsername: {
+┊ ┊34┊ color: 'red',
+┊ ┊35┊ fontWeight: 'bold',
+┊ ┊36┊ paddingBottom: 12,
+┊ ┊37┊ },
+┊ ┊38┊ messageTime: {
+┊ ┊39┊ color: '#8c8c8c',
+┊ ┊40┊ fontSize: 11,
+┊ ┊41┊ textAlign: 'right',
+┊ ┊42┊ },
+┊ ┊43┊ messageSpacer: {
+┊ ┊44┊ flex: 0.2,
+┊ ┊45┊ },
+┊ ┊46┊});
+┊ ┊47┊
+┊ ┊48┊class Message extends PureComponent {
+┊ ┊49┊ render() {
+┊ ┊50┊ const { color, message, isCurrentUser } = this.props;
+┊ ┊51┊
+┊ ┊52┊ return (
+┊ ┊53┊ <View key={message.id} style={styles.container}>
+┊ ┊54┊ {isCurrentUser ? <View style={styles.messageSpacer} /> : undefined }
+┊ ┊55┊ <View
+┊ ┊56┊ style={[styles.message, isCurrentUser && styles.myMessage]}
+┊ ┊57┊ >
+┊ ┊58┊ <Text
+┊ ┊59┊ style={[
+┊ ┊60┊ styles.messageUsername,
+┊ ┊61┊ { color },
+┊ ┊62┊ ]}
+┊ ┊63┊ >{message.from.username}</Text>
+┊ ┊64┊ <Text>{message.text}</Text>
+┊ ┊65┊ <Text style={styles.messageTime}>{moment(message.createdAt).format('h:mm A')}</Text>
+┊ ┊66┊ </View>
+┊ ┊67┊ {!isCurrentUser ? <View style={styles.messageSpacer} /> : undefined }
+┊ ┊68┊ </View>
+┊ ┊69┊ );
+┊ ┊70┊ }
+┊ ┊71┊}
+┊ ┊72┊
+┊ ┊73┊Message.propTypes = {
+┊ ┊74┊ color: PropTypes.string.isRequired,
+┊ ┊75┊ message: PropTypes.shape({
+┊ ┊76┊ createdAt: PropTypes.string.isRequired,
+┊ ┊77┊ from: PropTypes.shape({
+┊ ┊78┊ username: PropTypes.string.isRequired,
+┊ ┊79┊ }),
+┊ ┊80┊ text: PropTypes.string.isRequired,
+┊ ┊81┊ }).isRequired,
+┊ ┊82┊ isCurrentUser: PropTypes.bool.isRequired,
+┊ ┊83┊};
+┊ ┊84┊
+┊ ┊85┊export default Message;We add Messages to AppNavigator so it will stack on top of our Main screen when we navigate to it:
@@ -9,6 +9,7 @@
┊ 9┊ 9┊import { connect } from 'react-redux';
┊10┊10┊
┊11┊11┊import Groups from './screens/groups.screen';
+┊ ┊12┊import Messages from './screens/messages.screen';
┊12┊13┊
┊13┊14┊const styles = StyleSheet.create({
┊14┊15┊ container: {@@ -45,6 +46,9 @@
┊45┊46┊
┊46┊47┊const AppNavigator = StackNavigator({
┊47┊48┊ Main: { screen: MainScreenNavigator },
+┊ ┊49┊ Messages: { screen: Messages },
+┊ ┊50┊}, {
+┊ ┊51┊ mode: 'modal',
┊48┊52┊});
┊49┊53┊
┊50┊54┊// reducer initialization codeFinally, modify Groups to handle pressing a Group. We can use props.navigation.navigate, which is passed to our Groups component via React Navigation, to push the Messages Screen:
@@ -37,11 +37,18 @@
┊37┊37┊}));
┊38┊38┊
┊39┊39┊class Group extends Component {
+┊ ┊40┊ constructor(props) {
+┊ ┊41┊ super(props);
+┊ ┊42┊
+┊ ┊43┊ this.goToMessages = this.props.goToMessages.bind(this, this.props.group);
+┊ ┊44┊ }
+┊ ┊45┊
┊40┊46┊ render() {
┊41┊47┊ const { id, name } = this.props.group;
┊42┊48┊ return (
┊43┊49┊ <TouchableHighlight
┊44┊50┊ key={id}
+┊ ┊51┊ onPress={this.goToMessages}
┊45┊52┊ >
┊46┊53┊ <View style={styles.groupContainer}>
┊47┊54┊ <Text style={styles.groupName}>{`${name}`}</Text>@@ -52,6 +59,7 @@
┊52┊59┊}
┊53┊60┊
┊54┊61┊Group.propTypes = {
+┊ ┊62┊ goToMessages: PropTypes.func.isRequired,
┊55┊63┊ group: PropTypes.shape({
┊56┊64┊ id: PropTypes.number,
┊57┊65┊ name: PropTypes.string,@@ -63,9 +71,19 @@
┊63┊71┊ title: 'Chats',
┊64┊72┊ };
┊65┊73┊
+┊ ┊74┊ constructor(props) {
+┊ ┊75┊ super(props);
+┊ ┊76┊ this.goToMessages = this.goToMessages.bind(this);
+┊ ┊77┊ }
+┊ ┊78┊
┊66┊79┊ keyExtractor = item => item.id.toString();
┊67┊80┊
-┊68┊ ┊ renderItem = ({ item }) => <Group group={item} />;
+┊ ┊81┊ goToMessages(group) {
+┊ ┊82┊ const { navigate } = this.props.navigation;
+┊ ┊83┊ navigate('Messages', { groupId: group.id, title: group.name });
+┊ ┊84┊ }
+┊ ┊85┊
+┊ ┊86┊ renderItem = ({ item }) => <Group group={item} goToMessages={this.goToMessages} />;
┊69┊87┊
┊70┊88┊ render() {
┊71┊89┊ // render list of groups for user@@ -80,5 +98,10 @@
┊ 80┊ 98┊ );
┊ 81┊ 99┊ }
┊ 82┊100┊}
+┊ ┊101┊Groups.propTypes = {
+┊ ┊102┊ navigation: PropTypes.shape({
+┊ ┊103┊ navigate: PropTypes.func,
+┊ ┊104┊ }),
+┊ ┊105┊};
┊ 83┊106┊
┊ 84┊107┊export default Groups;Our app should now have simple layouts and routing for showing groups and pressing into a group to show that group’s message thread:
Time to connect our data!
On our server, we created a user query which will give our client access to plenty of data for a given User. Let’s use this query in our Groups component to get the user’s list of groups. It’s good form to keep queries separate of components because queries can often be reused by multiple components. We will create a new folder client/src/graphql to house all our queries, and create user.query.js inside this folder:
@@ -0,0 +1,18 @@
+┊ ┊ 1┊import gql from 'graphql-tag';
+┊ ┊ 2┊
+┊ ┊ 3┊// get the user and all user's groups
+┊ ┊ 4┊export const USER_QUERY = gql`
+┊ ┊ 5┊ query user($id: Int) {
+┊ ┊ 6┊ user(id: $id) {
+┊ ┊ 7┊ id
+┊ ┊ 8┊ email
+┊ ┊ 9┊ username
+┊ ┊10┊ groups {
+┊ ┊11┊ id
+┊ ┊12┊ name
+┊ ┊13┊ }
+┊ ┊14┊ }
+┊ ┊15┊ }
+┊ ┊16┊`;
+┊ ┊17┊
+┊ ┊18┊export default USER_QUERY;This query should look just like something we would insert into GraphQL Playground. We just use graphql-tag to parse the query so that our client will make the proper GraphQL request to the server.
Inside groups.screen.js, we will import USER_QUERY and connect it to the Groups component via react-apollo. react-apollo exposes a graphql module which requires a query, and can be passed an Object with optional configuration parameters as its second argument. Using this second argument, we can declare variables that will be passed to the query:
import { graphql, compose } from 'react-apollo';
import { USER_QUERY } from '../graphql/user.query';
// graphql() returns a func that can be applied to a React component
// set the id variable for USER_QUERY using the component's existing props
const userQuery = graphql(USER_QUERY, {
options: (ownProps) => ({ variables: { id: ownProps.id }}),
});
// Groups props will now have a 'data' paramater with the results from graphql (e.g. this.props.data.user)
export default userQuery(Groups);When we apply userQuery to the Groups component, Groups’ props will now also contain a data property with a loading parameter and the name of our Query (user):
Groups.propTypes = {
...
data: {
loading: PropTypes.bool,
user: PropTypes.shape({
id: PropTypes.number.isRequired,
email: PropTypes.string.isRequired,
groups: PropTypes.arrayOf(
PropTypes.shape({
id: PropTypes.number.isRequired,
name: PropTypes.string.isRequired,
}),
),
}),
}
};When the Query is loading, props.data.loading will be true and props.data.user will be undefined. When data is returned, props.data.loading will be false and props.data.user will be populated. There is also a neat trick we can do using the props parameter of options we pass to graphql:
const userQuery = graphql(USER_QUERY, {
options: (ownProps) => ({ variables: { id: ownProps.id } }),
props: ({ data: { loading, user } }) => ({
loading, user,
}),
});By using the props parameter in the graphql options, we can shape how we want the data to look on our component’s props. Here, we eliminate the data piece from Groups.props and directly place loading and user onto Groups.props.
Finally, we’ll modify our Groups component to render a loading screen while we are loading, and a list of Groups once we receive the data:
@@ -1,19 +1,26 @@
-┊ 1┊ ┊import { _ } from 'lodash';
┊ 2┊ 1┊import PropTypes from 'prop-types';
┊ 3┊ 2┊import React, { Component } from 'react';
┊ 4┊ 3┊import {
┊ 5┊ 4┊ FlatList,
+┊ ┊ 5┊ ActivityIndicator,
┊ 6┊ 6┊ StyleSheet,
┊ 7┊ 7┊ Text,
┊ 8┊ 8┊ TouchableHighlight,
┊ 9┊ 9┊ View,
┊10┊10┊} from 'react-native';
+┊ ┊11┊import { graphql } from 'react-apollo';
+┊ ┊12┊
+┊ ┊13┊import { USER_QUERY } from '../graphql/user.query';
┊11┊14┊
┊12┊15┊const styles = StyleSheet.create({
┊13┊16┊ container: {
┊14┊17┊ backgroundColor: 'white',
┊15┊18┊ flex: 1,
┊16┊19┊ },
+┊ ┊20┊ loading: {
+┊ ┊21┊ justifyContent: 'center',
+┊ ┊22┊ flex: 1,
+┊ ┊23┊ },
┊17┊24┊ groupContainer: {
┊18┊25┊ flex: 1,
┊19┊26┊ flexDirection: 'row',@@ -30,12 +37,6 @@
┊30┊37┊ },
┊31┊38┊});
┊32┊39┊
-┊33┊ ┊// create fake data to populate our ListView
-┊34┊ ┊const fakeData = () => _.times(100, i => ({
-┊35┊ ┊ id: i,
-┊36┊ ┊ name: `Group ${i}`,
-┊37┊ ┊}));
-┊38┊ ┊
┊39┊40┊class Group extends Component {
┊40┊41┊ constructor(props) {
┊41┊42┊ super(props);@@ -86,11 +87,22 @@
┊ 86┊ 87┊ renderItem = ({ item }) => <Group group={item} goToMessages={this.goToMessages} />;
┊ 87┊ 88┊
┊ 88┊ 89┊ render() {
+┊ ┊ 90┊ const { loading, user } = this.props;
+┊ ┊ 91┊
+┊ ┊ 92┊ // render loading placeholder while we fetch messages
+┊ ┊ 93┊ if (loading || !user) {
+┊ ┊ 94┊ return (
+┊ ┊ 95┊ <View style={[styles.loading, styles.container]}>
+┊ ┊ 96┊ <ActivityIndicator />
+┊ ┊ 97┊ </View>
+┊ ┊ 98┊ );
+┊ ┊ 99┊ }
+┊ ┊100┊
┊ 89┊101┊ // render list of groups for user
┊ 90┊102┊ return (
┊ 91┊103┊ <View style={styles.container}>
┊ 92┊104┊ <FlatList
-┊ 93┊ ┊ data={fakeData()}
+┊ ┊105┊ data={user.groups}
┊ 94┊106┊ keyExtractor={this.keyExtractor}
┊ 95┊107┊ renderItem={this.renderItem}
┊ 96┊108┊ />@@ -102,6 +114,24 @@
┊102┊114┊ navigation: PropTypes.shape({
┊103┊115┊ navigate: PropTypes.func,
┊104┊116┊ }),
+┊ ┊117┊ loading: PropTypes.bool,
+┊ ┊118┊ user: PropTypes.shape({
+┊ ┊119┊ id: PropTypes.number.isRequired,
+┊ ┊120┊ email: PropTypes.string.isRequired,
+┊ ┊121┊ groups: PropTypes.arrayOf(
+┊ ┊122┊ PropTypes.shape({
+┊ ┊123┊ id: PropTypes.number.isRequired,
+┊ ┊124┊ name: PropTypes.string.isRequired,
+┊ ┊125┊ }),
+┊ ┊126┊ ),
+┊ ┊127┊ }),
┊105┊128┊};
┊106┊129┊
-┊107┊ ┊export default Groups;
+┊ ┊130┊const userQuery = graphql(USER_QUERY, {
+┊ ┊131┊ options: () => ({ variables: { id: 1 } }), // fake the user for now
+┊ ┊132┊ props: ({ data: { loading, user } }) => ({
+┊ ┊133┊ loading, user,
+┊ ┊134┊ }),
+┊ ┊135┊});
+┊ ┊136┊
+┊ ┊137┊export default userQuery(Groups);By passing in {id: 1} for our variables, we are pretending to be logged in as the User with id = 1. In Part 7 of these tutorials, we will add authentication to our application so we don’t have to fake it anymore.
With our server running, if we refresh the application, we should see the groups displayed for User id = 1: 
react-apollo actually gives us multiple ways to connect data from a GraphQL Query to a React component.
- The most straightforward way is to use the
graphqlmodule fromreact-apollo:
import { graphql } from 'react-apollo';
...
// graqphql(QUERY, queryConfig)(Component)
const componentWithData = graphql(USER_QUERY, {
options: () => ({ variables: { id: 1 } }),
props: ({ data: { loading, user } }) => ({
loading, user,
}),
})(Groups);
export default componentWithData;withApollogives direct access to yourApolloClientinstance as a prop to your wrapped component. If you’re trying to do something fancy with custom logic like a one-off query, this module let’s you take charge of how your component gets its data:
import { withApollo } from 'react-apollo';
import ApolloClient from 'apollo-client';
Groups.propTypes = {
client: React.PropTypes.instanceOf(ApolloClient),
}
// GroupsWithApollo now has props.client with ApolloClient
const GroupsWithApollo = withApollo(Groups);- My personal favorite method is the
react-apollocomposemodule, which makes it easy to elegantly attach multiple queries, mutations, subscriptions, and your Redux store to the component in a single assignment:
import { graphql, compose } from 'react-apollo';
import { connect } from 'react-redux';
...
const userQuery = graphql(USER_QUERY, {
options: () => ({ variables: { id: 1 } }),
props: ({ data: { loading, user } }) => ({
loading, user,
}),
});
const otherQuery = graphql(OTHER_QUERY, otherConfig);
// this is fire!
const componentWithData = compose(
userQuery, // first query
otherQuery, // second query
connect(mapStateToProps, mapDispatchToProps), // redux
)(Groups);
export default componentWithData;I think this might be a good moment to reflect on the coolness of GraphQL.
In the olden days, to get data for the Screen for our Messages, we might start by consuming a REST API that gets Messages. But later down the line, we might also need to show details about the Group. In order to accomplish this, we would either have to make calls to different endpoints for Group details and Messages associated with the Group, or stuff the Messages into our Group endpoint. Womp.
With GraphQL, we can run a single call for exactly what we need in whatever shape we want. We can think about getting data starting with a node and going down the graph. In this case, we can query for a Group, and within that Group, request the associated Messages in the amount we want, and modify that amount when we need.
This time, let’s try using compose. Our process will be similar to the one we used before:
- Create a GraphQL Query for getting the Group
- Add configuration params for our Query (like a variable to identify which Group we need)
- Use the react-apollo graphql module to wrap the Messages component, passing in the Query and configuration params. We’ll also use compose just to get a feel for it.
Let’s start by creating our query in
client/src/graphql/group.query.js:
@@ -0,0 +1,25 @@
+┊ ┊ 1┊import gql from 'graphql-tag';
+┊ ┊ 2┊
+┊ ┊ 3┊const GROUP_QUERY = gql`
+┊ ┊ 4┊ query group($groupId: Int!) {
+┊ ┊ 5┊ group(id: $groupId) {
+┊ ┊ 6┊ id
+┊ ┊ 7┊ name
+┊ ┊ 8┊ users {
+┊ ┊ 9┊ id
+┊ ┊10┊ username
+┊ ┊11┊ }
+┊ ┊12┊ messages {
+┊ ┊13┊ id
+┊ ┊14┊ from {
+┊ ┊15┊ id
+┊ ┊16┊ username
+┊ ┊17┊ }
+┊ ┊18┊ createdAt
+┊ ┊19┊ text
+┊ ┊20┊ }
+┊ ┊21┊ }
+┊ ┊22┊ }
+┊ ┊23┊`;
+┊ ┊24┊
+┊ ┊25┊export default GROUP_QUERY;So this Query is pretty cool. Given a groupId, we can get whatever features of the Group we need including the Messages. For now, we are asking for all the Messages in this Group. That’s a good starting point, but later we’ll modify this query to return a limited number of Messages at a time, and append more Messages as the user scrolls.
Finally, let’s attach our GROUP_QUERY to the Messages component:
@@ -1,5 +1,5 @@
-┊1┊ ┊import { _ } from 'lodash';
┊2┊1┊import {
+┊ ┊2┊ ActivityIndicator,
┊3┊3┊ FlatList,
┊4┊4┊ StyleSheet,
┊5┊5┊ View,@@ -7,8 +7,10 @@
┊ 7┊ 7┊import PropTypes from 'prop-types';
┊ 8┊ 8┊import React, { Component } from 'react';
┊ 9┊ 9┊import randomColor from 'randomcolor';
+┊ ┊10┊import { graphql, compose } from 'react-apollo';
┊10┊11┊
┊11┊12┊import Message from '../components/message.component';
+┊ ┊13┊import GROUP_QUERY from '../graphql/group.query';
┊12┊14┊
┊13┊15┊const styles = StyleSheet.create({
┊14┊16┊ container: {@@ -17,22 +19,10 @@
┊17┊19┊ flex: 1,
┊18┊20┊ flexDirection: 'column',
┊19┊21┊ },
-┊20┊ ┊});
-┊21┊ ┊
-┊22┊ ┊const fakeData = () => _.times(100, i => ({
-┊23┊ ┊ // every message will have a different color
-┊24┊ ┊ color: randomColor(),
-┊25┊ ┊ // every 5th message will look like it's from the current user
-┊26┊ ┊ isCurrentUser: i % 5 === 0,
-┊27┊ ┊ message: {
-┊28┊ ┊ id: i,
-┊29┊ ┊ createdAt: new Date().toISOString(),
-┊30┊ ┊ from: {
-┊31┊ ┊ username: `Username ${i}`,
-┊32┊ ┊ },
-┊33┊ ┊ text: `Message ${i}`,
+┊ ┊22┊ loading: {
+┊ ┊23┊ justifyContent: 'center',
┊34┊24┊ },
-┊35┊ ┊}));
+┊ ┊25┊});
┊36┊26┊
┊37┊27┊class Messages extends Component {
┊38┊28┊ static navigationOptions = ({ navigation }) => {@@ -42,22 +32,66 @@
┊42┊32┊ };
┊43┊33┊ };
┊44┊34┊
-┊45┊ ┊ keyExtractor = item => item.message.id.toString();
+┊ ┊35┊ constructor(props) {
+┊ ┊36┊ super(props);
+┊ ┊37┊ const usernameColors = {};
+┊ ┊38┊ if (props.group && props.group.users) {
+┊ ┊39┊ props.group.users.forEach((user) => {
+┊ ┊40┊ usernameColors[user.username] = randomColor();
+┊ ┊41┊ });
+┊ ┊42┊ }
+┊ ┊43┊
+┊ ┊44┊ this.state = {
+┊ ┊45┊ usernameColors,
+┊ ┊46┊ };
+┊ ┊47┊
+┊ ┊48┊ this.renderItem = this.renderItem.bind(this);
+┊ ┊49┊ }
+┊ ┊50┊
+┊ ┊51┊ componentWillReceiveProps(nextProps) {
+┊ ┊52┊ const usernameColors = {};
+┊ ┊53┊ // check for new messages
+┊ ┊54┊ if (nextProps.group) {
+┊ ┊55┊ if (nextProps.group.users) {
+┊ ┊56┊ // apply a color to each user
+┊ ┊57┊ nextProps.group.users.forEach((user) => {
+┊ ┊58┊ usernameColors[user.username] = this.state.usernameColors[user.username] || randomColor();
+┊ ┊59┊ });
+┊ ┊60┊ }
┊46┊61┊
-┊47┊ ┊ renderItem = ({ item: { isCurrentUser, message, color } }) => (
+┊ ┊62┊ this.setState({
+┊ ┊63┊ usernameColors,
+┊ ┊64┊ });
+┊ ┊65┊ }
+┊ ┊66┊ }
+┊ ┊67┊
+┊ ┊68┊ keyExtractor = item => item.id.toString();
+┊ ┊69┊
+┊ ┊70┊ renderItem = ({ item: message }) => (
┊48┊71┊ <Message
-┊49┊ ┊ color={color}
-┊50┊ ┊ isCurrentUser={isCurrentUser}
+┊ ┊72┊ color={this.state.usernameColors[message.from.username]}
+┊ ┊73┊ isCurrentUser={message.from.id === 1} // for now until we implement auth
┊51┊74┊ message={message}
┊52┊75┊ />
┊53┊76┊ )
┊54┊77┊
┊55┊78┊ render() {
+┊ ┊79┊ const { loading, group } = this.props;
+┊ ┊80┊
+┊ ┊81┊ // render loading placeholder while we fetch messages
+┊ ┊82┊ if (loading && !group) {
+┊ ┊83┊ return (
+┊ ┊84┊ <View style={[styles.loading, styles.container]}>
+┊ ┊85┊ <ActivityIndicator />
+┊ ┊86┊ </View>
+┊ ┊87┊ );
+┊ ┊88┊ }
+┊ ┊89┊
┊56┊90┊ // render list of messages for group
┊57┊91┊ return (
┊58┊92┊ <View style={styles.container}>
┊59┊93┊ <FlatList
-┊60┊ ┊ data={fakeData()}
+┊ ┊94┊ data={group.messages.slice().reverse()}
┊61┊95┊ keyExtractor={this.keyExtractor}
┊62┊96┊ renderItem={this.renderItem}
┊63┊97┊ ListEmptyComponent={<View />}@@ -67,4 +101,25 @@
┊ 67┊101┊ }
┊ 68┊102┊}
┊ 69┊103┊
-┊ 70┊ ┊export default Messages;
+┊ ┊104┊Messages.propTypes = {
+┊ ┊105┊ group: PropTypes.shape({
+┊ ┊106┊ messages: PropTypes.array,
+┊ ┊107┊ users: PropTypes.array,
+┊ ┊108┊ }),
+┊ ┊109┊ loading: PropTypes.bool,
+┊ ┊110┊};
+┊ ┊111┊
+┊ ┊112┊const groupQuery = graphql(GROUP_QUERY, {
+┊ ┊113┊ options: ownProps => ({
+┊ ┊114┊ variables: {
+┊ ┊115┊ groupId: ownProps.navigation.state.params.groupId,
+┊ ┊116┊ },
+┊ ┊117┊ }),
+┊ ┊118┊ props: ({ data: { loading, group } }) => ({
+┊ ┊119┊ loading, group,
+┊ ┊120┊ }),
+┊ ┊121┊});
+┊ ┊122┊
+┊ ┊123┊export default compose(
+┊ ┊124┊ groupQuery,
+┊ ┊125┊)(Messages);If we fire up the app, we should see our messages: 
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