Build a Chat App with Stream SDK

Introduction

Let’s build a fully-fledged Chat application with React Native and Stream Chat SDK. Shall we?

You can follow this build in video format here:

If you want to follow along, and build this application yourself, make sure to download the Asset bundle that contains all the dummy data, pre-defined components, PDF presentation and more.

Download the Asset Bundle 👇

To get the Source Code, PDF guide, dummy data, images, etc.

Context

This project is part of the notJust.Hack event, and the goal is to show you that it is possible to build a functional full-stack application in just 3 days.

During the first workshop, we built the UI of a Virtual Events Application. During the second workshop we have implemented the backend side (authentication, database, graphql api).

The goal for today

Most applications can benefit from in-app messaging experience, however building a premium experience, similar to what you get from apps like Whatsapp, Signal, etc., is a challenging task even for experienced developers.

Not anymore. With Stream Chat SDK you can implement a full-fledged messaging experience, in hours.

That’s exactly what we are going to do during today’s workshop.

We will build a premium messaging experience for our Virtual Events app 📅

✅ Private and Group messaging
✅ Message reaction
✅ Replies & Threads
✅ Attachements, URL previews, gifs
✅ and more

This workshop is sponsored by Stream, which powers Chat Messaging and Activity Feeds for billions of global end-users across thousands of different apps.

Let’s get started with Stream

Let’s start by creating a Stream account.

The Stream Maker Account provides qualifying teams with full and free access to Stream's Chat and Activity Feed APIs, making them accessible to side projects and new startups. No credit card is required. Try Stream for Free!

Create a new app

Create a new Stream App

Install

Follow the Stream installation guide for expo: https://getstream.io/chat/docs/sdk/reactnative/#expo-installation

Install stream-chat-expo

BASH

npx expo install stream-chat-expo

Install additional deps

BASH

npx expo install @react-native-community/netinfo expo-av expo-document-picker expo-file-system expo-haptics expo-image-manipulator expo-image-picker expo-media-library expo-sharing react-native-gesture-handler react-native-reanimated react-native-svg

Optional dependecies

BASH

npx expo install expo-av expo-clipboard

Make sure to follow these additional steps for some of the libraries we installed.

Prepare the Chat screens

Create a blank component for the Chats Screen inside screens/Chat/ChatsScreen.tsx
Create a new Stack Navigator for the Chat Screens inside navigation/ChatStackNavigator.tsx

JAVASCRIPT

import { createNativeStackNavigator } from '@react-navigation/native-stack';

import ChatsScreen from '../screens/Chat/ChatsScreen';

const Stack = createNativeStackNavigator();

export default () => {
  return (
    <Stack.Navigator>
      <Stack.Screen name="Chats" component={ChatsScreen} />
    </Stack.Navigator>
  );
};

Add the ChatStackNavigator as a tab inside BottomTabNavigator from navigation/index.tsx

JAVASCRIPT

<BottomTab.Screen
  name="Chat"
  component={ChatStackNavigator}
  options={{
    headerShown: false,
    tabBarIcon: ({ color }) => (
      <Ionicons name="chatbox-ellipses-outline" size={25} color={color} />
    ),
  }}
/>

Chat Context

Create a new ChatContext.tsx

JAVASCRIPT

import React, { createContext, useContext } from 'react';

type ChatContextType = {};

const ChatContext = createContext < ChatContextType > {};

const ChatContextProvider = ({ children }: { children: React.ReactNode }) => {
  const value = {};
  return <ChatContext.Provider value={value}>{children}</ChatContext.Provider>;
};

export const useChatContext = () => useContext(ChatContext);

export default ChatContextProvider;

And wrap our Chat Navigation Screens inside the ChatContextProvider

Connect the user to the chat client

In the ChatContextProvider let’s first setup the Stream Chat client

JAVASCRIPT

import { StreamChat } from 'stream-chat';

Now, let’s connect the user using the information from the Authenticated user

JAVASCRIPT

const user = useUserData();
const [chatClient, setChatClient] = useState<StreamChat>();
const [currentChannel, setCurrentChannel] = useState<Channel>();

useEffect(() => {
  const initChat = async () => {
    if (!user) {
      return;
    }
    const client = StreamChat.getInstance("APP key");

    await client.connectUser(
      {
        id: user.id,
        name: user.displayName,
        image: user.avatarUrl,
      },
      client.devToken(user.id)
    );

    setChatClient(client);
  };

  if (!chatClient) {
    initChat();
  }
}, [user?.id]);

useEffect(() => {
  return () => {
    chatClient?.disconnectUser();
    setChatClient(undefined);
  };
}, []);

const value = { chatClient, currentChannel, setCurrentChannel };

Enable Dev token

Tokens & Authentication

Create the global Channel

JAVASCRIPT

const globalChannel = client.channel('livestream', 'global', {
  name: 'notJust.dev',
});
await globalChannel.watch({ watchers: { limit: 100 } });

setChatClient(client);

UI Components

Wrap all the children of the Chat Context Provider with the OverlayProvider and Chat components

JAVASCRIPT

return (
  <ChatContext.Provider value={value}>
    <OverlayProvider>
      <Chat client={chatClient}>{children}</Chat>
    </OverlayProvider>
  </ChatContext.Provider>
);

Display the ChannelList inside screens/ChatScreens/ChatsScreen.tsx

JAVASCRIPT

import { useNavigation } from '@react-navigation/native';
import React from 'react';
import { ChannelList } from 'stream-chat-expo';
import { useChatContext } from '../../context/ChatContext';

const ChatsScreen = () => {
  const { setCurrentChannel } = useChatContext();
  const navigation = useNavigation();

  const onSelect = (chanel) => {
    setCurrentChannel(chanel);
    navigation.navigate('ChatRoom');
  };

  return <ChannelList onSelect={onSelect} />;
};

export default ChatsScreen;

Channel page

Display the Channel, MessageList and MessageInput components in screens/ChatScreens/ChatRoomScreen.tsx

JAVASCRIPT

import React from 'react';
import { Channel, MessageInput, MessageList } from 'stream-chat-expo';
import { useChatContext } from '../../context/ChatContext';

const ChatRoomScreen = () => {
  const { currentChannel } = useChatContext();

  return (
    <Channel channel={currentChannel}>
      <MessageList />
      <MessageInput />
    </Channel>
  );
};

export default ChatRoomScreen;

Private messages

Move the UsersScreen inside the ChatStackNavigator
Inside the UserListItem.tsx add the onPress event that will create a new chat room with that user, and then, will redirect there

JAVASCRIPT

const { chatClient, setCurrentChannel } = useChatContext();
const navigation = useNavigation();

const handleStartChat = async () => {
  if (!chatClient?.userID) return;

  try {
    const newChannel = chatClient.channel('messaging', {
      demo: 'virtual-event',
      members: [chatClient.userID, user.id],
    });

    await newChannel.watch();
    setCurrentChannel(newChannel);
    navigation.goBack();
    navigation.navigate('ChatRoom');
  } catch (err) {
    console.log(err);
  }
};

Group messaging

Let’s create a group chat room for every event we have.

When the user will Join an event, we will join the chat room associated with that event as well.

Let’s create the joinEventChatRoom function inside our ChatContext and export it through the context.

JAVASCRIPT

const joinEventChatRoom = async (event) => {
  if (!chatClient) {
    return;
  }
  const channelId = `room-${event.id}`;
  const eventChannel = chatClient.channel('livestream', channelId, {
    name: event.name,
  });

  await eventChannel.watch({ watchers: { limit: 100 } });
  setCurrentChannel(eventChannel);

  navigation.navigate('Root', {
    screen: 'Chat',
  });
  navigation.navigate('Root', {
    screen: 'Chat',
    params: { screen: 'ChatRoom' },
  });
};

In the ModalScreen.tsx add a new button the will call the joinEventChatRoom

JAVASCRIPT

const { joinEventChatRoom } = useChatContext();
...

<CustomButton
	text="Join the conversation"
	onPress={() => joinEventChatRoom(event)}
/>

To have access the the ChatContextProvider , we have to wrap all the screens (except auth screens). For that, move the ChatContextProvider from ChatStackNavigator to navigation/index.tsx inside the RootNavigator.

Hurray 🎉

Congrats, you have successfully build a chatting mobile application using React Native and Stream Chat SDK.

I hope you found this workshop valueble and if you ever need chatting functionalities in your app, you know where to look for.

Resources

React Native SDK for Chat Messaging

React Native Chat Tutorial

Getting Started | Stream Chat - React Native SDK Docs

Build a Chat App with Stream SDK

Introduction

Download the Asset Bundle 👇

Context

The goal for today

Let’s get started with Stream

Create a new app

Install

Prepare the Chat screens

Chat Context

Connect the user to the chat client

Create the global Channel

UI Components

Channel page

Private messages

Group messaging

Hurray 🎉

Resources

Vadim Savin