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Chat SDKs Android v4
Chat SDKs Android
Chat SDKs
Version 4

Set up push notifications for FCM

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This part covers the following step-by-step instructions of our push notifications for FCM.

Note: See Set up push notifications for HMS if you want to see the instructions for HMS push notifications.

Step 1: Generate server key for FCM

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The Sendbird server requires your server key to send notification requests to FCM on behalf of your server. This is required for FCM to authorize HTTP requests.

If you already have your server key, you can skip this step and go directly to Step 2: Register server key to Sendbird Dashboard.

  1. Go to the Firebase console. If you don't have a Firebase project for your client app, create a new project.

  1. Select your project card to move to Project Overview.

  2. Click the gear icon at the upper left corner and select Project settings.

  1. Go to Cloud Messaging > Project credentials and copy your server key.

  1. Go to the General tab and select your Android app to add Firebase to. During the registration process, enter your package name, download the google-services.json file, and place it in your Android app module root directory.

Step 2: Register server key to Sendbird Dashboard

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Register your server key to Sendbird Dashboard as follows. Your server key can also be registered using the add an FCM push configuration API.

  1. Sign in to your dashboard and go to Settings > Chat > Push notifications.

  2. Turn on Notifications and select Send to devices both offline and online.

  3. Click Add credentials and register the app ID and app secret acquired at Step 1.

Step 3: Set up Firebase and the FCM SDK

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Add the following dependency for the Cloud Messaging Android library to your build.gradle file as below.

Note: The firebase-messaging version should be 19.0.1 or higher.

dependencies {
    // ...
    implementation 'com.google.firebase:firebase-messaging:23.0.1'

Then the Chat SDK writes and declares our push notifications with multi-device support in the manifest while you build your client app. If you declare another push service that extends FirebaseMessagingService in your client app's manifest, this multi-device support doesn't work in the app.

Note: To learn more about this step, refer to Firebase's Set Up a Firebase Cloud Messaging client app on Android guide. The Google FCM sample project guide is another helpful reference.

Step 4: Implement multi-device support in your Android app

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The following classes and interface are provided to implement push notifications with multi-device support.

Class or interfaceDescription


A class that provides the onNewToken() and onMessageReceived() callbacks as well as other callbacks to handle a user's registration token and receive notification messages from FCM.


A class that provides the methods to register and unregister a SendbirdPushHandler handler, check if the same message has already been received, and more.


An interface that contains the onReceived() callback to receive a user's registration token from FCM.

These are used to inherit your MyFirebaseMessagingService class from the SendbirdPushHandler class and implement the following.

class MyFirebaseMessagingService : SendbirdPushHandler() {
    // This is invoked when a notification message has been delivered to the current user's client app.
    override fun onMessageReceived(context: Context, remoteMessage: RemoteMessage) {
        try {
            val pushTitle = remoteMessage.data["push_title"]
            val message = remoteMessage.data["message"]
            val payload = remoteMessage.data["sendbird"] ?: return
            val sendbirdJson = JSONObject(payload)
            val channelJson = sendbirdJson.getJSONObject("channel")
            val channelUrl = channelJson.getString("channel_url")

            // If you want to customize a notification with the received FCM message,
            // write your method like sendNotification() below.
            sendNotification(context, pushTitle, message, channelUrl)
        } catch (e: JSONException) {

    override fun onNewToken(newToken: String?) {
        pushToken = newToken

    override val isUniquePushToken: Boolean
        get() = false

    // The alwaysReceiveMessage() method determines whether push notifications for new messages
    // are delivered even when the app is in foreground.
    // The default is false, meaning push notifications are delivered
    // only when the app is in the background.
    override fun alwaysReceiveMessage(): Boolean {
        return false

    fun sendNotification(context: Context, messageTitle: String?, messageBody: String?, channelUrl: String) {
        // Customize your notification containing the received FCM message.

    companion object {
        var pushToken: String? = null
        fun getPushToken(callback: ((pushToken: String?, e: SendbirdException?) -> Unit)) {
            if (!pushToken.isNullOrEmpty()) {
                callback(pushToken, null)

            SendbirdPushHelper.getPushToken { token, e ->
                if (token != null) {
                    pushToken = token
                callback(pushToken, e)

Note: Upon initial startup of your app, the FCM SDK generates a unique and app-specific registration token for the client app instance on your user's device. FCM uses this registration token to determine which device to send notification messages to.

In order to receive information about push notification events for the current user from the Sendbird server, register a MyFireBaseMessagingService instance to SendbirdPushHelper as an event handler.

To receive a push notification when the app is in the background or closed, you must register the MyFireBaseMessagingService instance. This instance isn't dependent on Sendbird Chat SDK, so even in cases where Sendbird.init() isn't called in Application, MyFireBaseMessagingService must be registered in the Application instance's onCreate() method as shown in the code below.

class MyApplication : Application() {
    override fun onCreate() {
            InitParams(APP_ID, applicationContext, true),
            object : InitResultHandler {
                override fun onMigrationStarted() {}
                override fun onInitFailed(e: SendbirdException) {}
                override fun onInitSucceed() {}
        // Not dependent on SendbirdChat.init(). Must be called in Application.

Also, register a MyFireBaseMessagingService instance when a user logs into the Sendbird server as follows.

SendbirdChat.connect(USER_ID) { user, e ->
    if (e != null) {
        // Handle error.
    // ...


The instance should be unregistered when a user logs out from the Sendbird server as follows.

    object : SendbirdPushHelper.OnPushRequestCompleteListener {
        override fun onComplete(isRegistered: Boolean, token: String?) {
            SendbirdChat.disconnect {
                // Clear user-related data.

        override fun onError(e: SendbirdException) {
            // Handle error.

Step 5: Handle an FCM message payload

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The Sendbird server sends push notification payloads as FCM data messages, which contain notification-related data in the form of key-value pairs. Unlike notification messages, the client app needs to parse and process these data messages in order to display them as local notifications.

The following code shows how to receive a push notification payload and parse it as a local notification. The payload consists of two properties: message and sendbird. The message property is a string generated according to a push notification template you set on the Sendbird Dashboard. The sendbird property is a JSON object which contains all the information about the message a user has sent. Within MyFirebaseMessagingService.kotlin, you can show the parsed messages to users as a notification using your custom sendNotification() method.

Note: See Firebase’s Receive messages in an Android app guide to learn more about how to implement code to receive and parse a FCM notification message, how notification messages are handled depending on the state of the receiving app, how to edit the app manifest, or how to override the onMessageReceived method.

override fun onMessageReceived(remoteMessage: RemoteMessage) {
    try {
        if (remoteMessage.getData().containsKey("sendbird")) {
            val sendbird = JSONObject(remoteMessage.getData().get("sendbird"))
            val channel = sendbird.get("channel") as JSONObject
            val channelUrl = channel["channel_url"] as String
            val messageTitle = sendbird.get("push_title") as String
            val messageBody = sendbird.get("message") as String
            // If you want to customize a notification with the received FCM message,
            // write your method like sendNotification() below.
            sendNotification(context, messageTitle, messageBody, channelUrl)
    } catch (e: JSONException) {
// ...
fun sendNotification(
    context: Context,
    messageTitle: String,
    messageBody: String,
    channelUrl: String
) {
    // Implement your own way to create and show a notification containing the received FCM message.
    val notificationBuilder = NotificationCompat.Builder(context, channelUrl)
    .setColor(Color.parseColor("#7469C4")) // small icon background color
    .setLargeIcon(BitmapFactory.decodeResource(context.resources, R.drawable.logo_sendbird))

The following is a complete payload format of the sendbird property, which contains a set of provided key-value items. Some fields in the push notification payload can be customized in Settings > Chat > Notifications on Sendbird Dashboard. For example, push_title and push_alert are created based on Title and Body text you set in Push notification content templates, respectively, in the Push notifications menu. In order to display them in a local notification, pass push_title and push_alert of the push notification payload into the setContentTitle and setContentText methods of the NotificationCompat.Builder class, respectively. Also, the channel_unread_count field can be added into or removed from the payload in the same menu on the Sendbird Dashboard.

    "category": "messaging:offline_notification",
    "type": string,                 // Message type: MESG, FILE, or ADMM
    "message": string,              // User input message
    "custom_type": string,          // Custom message type
    "message_id": long,          // Message ID
    "created_at": long,          // The time that the message was created, in a 13-digit Unix milliseconds format
    "app_id": string,                // Application's unique ID
    "unread_message_count": int,    // Total number of new messages unread by the user
    "channel": {
        "channel_url": string,      // Group channel URL
        "name": string,          // Group channel name
        "custom_type": string,       // Custom Group channel type
        "channel_unread_count": int // Total number of unread new messages from the specific channel
    "channel_type": string,         // A value of channel_type is set by the system. The value of messaging indicates a distinct group channel while the value of group_messaging indicates a private group channel and chat indicates all other cases.
    "sender": {
        "id": string,                // Sender's unique ID
        "name": string,          // Sender's nickname
        "profile_url": string,       // Sender's profile image URL
        "require_auth_for_profile_image": false,
        "metadata": {}
    "recipient": {
        "id": string,                // Recipient's unique ID
        "name": string              // Recipient's nickname
    "files": [],                        // An array of data regarding the file message, such as filename
    "translations": {},          // The items of locale:translation
    "push_title": string,           // Title of a notification message that can be customized on the Sendbird Dashboard with or without variables
    "push_alert": string,           // Body text of a notification message that can be customized on the Sendbird Dashboard with or without variables
    "push_sound": string,           // The location of a sound file for notifications
    "audience_type": string,            // The type of audiences for notifications
    "mentioned_users": {
        "user_id": string,          // The ID of a mentioned user
        "nickname": string,         // The nickname of a mentioned user
        "profile_url": string,      // Mentioned user's profile image URL
        "require_auth_for_profile_image": false

Step 6: Enable multi-device support on Sendbird Dashboard

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After the above implementation has been completed, multi-device support should be enabled on Sendbird Dashboard by going to Settings > Application > Notifications > Push notifications for multi-device users.