This guide demonstrates how to add chat to a React Native application using CometChat. Before you begin, we strongly recommend you read the Key Concepts guide.

Get your Application Keys

Signup for CometChat and then:

1. Create a new app
2. Head over to the API Keys section and click on the Create API Key button
3. Enter a name and select the scope as Auth Only
4. Now note the API Key and App ID

Add the CometChat Dependency

NPM

First, install via npm

npm install @cometchat-pro/[email protected] --save

Then, import the CometChat object wherever you want to use CometChat

import { CometChat } from "@cometchat-pro/react-native-chat"

Initialize CometChat

We suggest you call the init() method on app startup, preferably in the index.js file.

var appID = "APP_ID";
var region = "REGION";
var appSetting = new CometChat.AppSettingsBuilder().subscribePresenceForAllUsers().setRegion(region).build();
CometChat.init(appID, appSetting).then(
  () => {
    console.log("Initialization completed successfully");
    // You can now call login function.
  },
  error => {
    console.log("Initialization failed with error:", error);
    // Check the reason for error and take appropriate action.
  }
);

Make sure you replace the APP_ID with your CometChat App ID and REGION with your app region in the above code.

Register and Login your user

Once initialization is successful, you will need to create a user.
To create users on the fly, you can use the createUser() method. This method takes a User object and the API Key as input parameters and returns the created User object if the request is successful.

let apiKey = "API_KEY";
var uid = "user1";
var name = "Kevin";

var user = new CometChat.User(uid);

user.setName(name);

CometChat.createUser(user, apiKey).then(
    user => {
        console.log("user created", user);
    },error => {
        console.log("error", error);
    }
)

Make sure that UID and name are specified as these are mandatory fields to create a user.

Once you have created the user successfully, you will need to log the user into CometChat using the login() method.

We recommend you call the CometChat login() method once your user logs into your app. The login() method needs to be called only once.

var UID = "SUPERHERO1";
var apiKey = "API_KEY";

CometChat.login(UID, apiKey).then(
  user => {
    console.log("Login Successful:", { user });    
  },
  error => {
    console.log("Login failed with exception:", { error });    
  }
);

Make sure you replace the API_KEY with your CometChat API Key in the above code.

📘

Sample Users

We have set-up 5 users for testing having UIDs: SUPERHERO1, SUPERHERO2, SUPERHERO3, SUPERHERO4 and SUPERHERO5.

The login() method returns the User object containing all the information of the logged-in user.

🚧

UID can be alphanumeric with underscore and hyphen. Spaces, punctuation and other special characters are not allowed.

Send a message

Once your user has logged in, you can send a message using the sendMessage() method.

var receiverID = "SUPERHERO2";
var messageText = "Hello";
var receiverType = CometChat.RECEIVER_TYPE.USER;

var textMessage = new CometChat.TextMessage(receiverID, messageText, receiverType);

CometChat.sendMessage(textMessage).then(
  message => {
    console.log("Message sent successfully:", message);
    // Do something with message
  },
  error => {
    console.log("Message sending failed with error:", error);
    // Handle any error
  }
);

Once the message is sent successfully, you will receive the message information as the TextMessage object on Promise resolved.

Receive Messages

You can add multiple MessageListener using the addMessageListener() method, to receive incoming messages wherever you need.

var listenerID = "UNIQUE_LISTENER_ID";

CometChat.addMessageListener(
  listenerID, 
  new CometChat.MessageListener({
    onTextMessageReceived: message => {
      console.log("Message received successfully:", message);
      // Handle text message
    }
  })
 );