Mentions

Mention specific users in messages to enhance engagement and collaboration in group conversations

Quick Reference for AI Agents & Developers

// Send message with mention to user
val textMessage = TextMessage("UID", "Hello <@uid:cometchat-uid-1>", CometChatConstants.RECEIVER_TYPE_USER)
CometChat.sendMessage(textMessage, object : CallbackListener<TextMessage>() {
    override fun onSuccess(message: TextMessage) { }
    override fun onError(e: CometChatException) { }
})

// Check if logged-in user was mentioned
val wasMentioned = message.hasMentionedMe()

// Get list of mentioned users
val mentionedUsers = message.mentionedUsers

Available via: SDK | REST API | UI Kits

Mentions

Mentions are a powerful tool for enhancing communication in messaging platforms. They streamline interaction by allowing users to easily engage and collaborate with particular individuals, especially in group conversations.

Mentions in messages enable users to refer to specific individuals within a conversation.

Send Mentioned Messages

Every User object has a String unique identifier associated with them which can be found in a property called uid. To mention a user in a message, the message text should contain the uid in following format: <@uid:UID_OF_THE_USER>. For example, to mention the user with UID cometchat-uid-1 in a text message, your text should be "<@uid:cometchat-uid-1>"

Before sending messages with mentions, ensure you have initialized the SDK and logged in a user.

To User

Kotlin

private val receiverID = "UID"
private val messageText = "Hello <@uid:cometchat-uid-1>"
private val receiverType = CometChatConstants.RECEIVER_TYPE_USER

val textMessage = TextMessage(receiverID, messageText, receiverType)
CometChat.sendMessage(textMessage, object : CallbackListener<TextMessage>() {
  override fun onSuccess(textMessage: TextMessage) {
      Log.d(TAG, "Message sent successfully: $textMessage")
  }

  override fun onError(e: CometChatException) {
      Log.d(TAG, "Message sending failed with exception: " + e.message)
  }
})

Java

private String receiverID = "UID";
private String messageText = "Hello, <@uid:cometchat-uid-1>";
private String receiverType = CometChatConstants.RECEIVER_TYPE_USER;

TextMessage textMessage = new TextMessage(receiverID, messageText, receiverType);

CometChat.sendMessage(textMessage, new CometChat.CallbackListener<TextMessage>() {
  @Override
  public void onSuccess(TextMessage textMessage) {
      Log.d(TAG, "Message sent successfully: " + textMessage.toString());
  }

  @Override
  public void onError(CometChatException e) {
      Log.d(TAG, "Message sending failed with exception: " + e.getMessage());
  }
});

To Group

Kotlin

private val receiverID = "GUID"
private val messageText = "Hello <@uid:cometchat-uid-1>"
private val receiverType = CometChatConstants.RECEIVER_TYPE_GROUP

val textMessage = TextMessage(receiverID, messageText, receiverType)
CometChat.sendMessage(textMessage, object : CallbackListener<TextMessage>() {
  override fun onSuccess(textMessage: TextMessage) {
      Log.d(TAG, "Message sent successfully: $textMessage")
  }

  override fun onError(e: CometChatException) {
      Log.d(TAG, "Message sending failed with exception: " + e.message)
  }
})

Java

private String receiverID = "GUID";
private String messageText = "Hello <@uid:cometchat-uid-1>";
private String receiverType = CometChatConstants.RECEIVER_TYPE_GROUP;

TextMessage textMessage = new TextMessage(receiverID, messageText, receiverType);

CometChat.sendMessage(textMessage, new CometChat.CallbackListener<TextMessage>() {
  @Override
  public void onSuccess(TextMessage textMessage) {
      Log.d(TAG, "Message sent successfully: " + textMessage.toString());
  }

  @Override
  public void onError(CometChatException e) {
      Log.d(TAG, "Message sending failed with exception: " + e.getMessage());
  }
});

You can mention user in text message and media messages captions

Mentioned Messages

By default, the SDK will fetch all the messages irrespective of the fact that the logged-in user is mentioned or not in the message. The SDK has other optional filters such as tag info and blocked info. For more filtering options, see Additional Message Filtering.

Setting	Description
mentionsWithTagInfo(boolean value)	If set to true, SDK will fetch a list of messages where users are mentioned & will also fetch the tags of the mentioned users. Default value = false.
mentionsWithBlockedInfo(boolean value)	If set to true, SDK will fetch a list of messages where users are mentioned & will also fetch their blocked relationship with the logged-in user. Default value = false.

Mentions With Tag Info

To get a list of messages in a conversation where users are mentioned along with the user tags of the mentioned users.

To User

Kotlin

val UID = "cometchat-uid-1"

val messagesRequest = MessagesRequest.MessagesRequestBuilder()
  .setLimit(50)
  .setUID(UID)
  .mentionsWithTagInfo(true)
  .build()

messagesRequest.fetchPrevious(object : CometChat.CallbackListener<List<BaseMessage>>() {
  override fun onSuccess(messages: List<BaseMessage>) {
      for (messageObj in messages) {
          for (user in messageObj.mentionedUsers) {
              Log.e(TAG, "tag: ${user.tags}")
          }
      }
  }

  override fun onError(e: CometChatException) {
      Log.e(TAG, "onError: " + e)
  }
})

Java

String UID = "cometchat-uid-1";

MessagesRequest messagesRequest = new MessagesRequest.MessagesRequestBuilder()
.setLimit(50)
.setUID(UID)
.mentionsWithTagInfo(true)
.build();

messagesRequest.fetchPrevious(new CometChat.CallbackListener<List<BaseMessage>>() {
  @Override
  public void onSuccess(List<BaseMessage> messages) {
    for (BaseMessage messageObj: messages){
      for (User user: messageObj.getMentionedUsers()){
        Log.e(TAG, "tag: " + user.getTags());
      }
    }
  }

  @Override
  public void onError(CometChatException e) {
    Log.e(TAG, "onError: " + e);
  }
});

To Group

Kotlin

val GUID = "cometchat-guid-1"

val messagesRequest = MessagesRequest.MessagesRequestBuilder()
  .setLimit(50)
  .setGUID(GUID)
  .mentionsWithTagInfo(true)
  .build()

messagesRequest.fetchPrevious(object : CometChat.CallbackListener<List<BaseMessage>>() {
  override fun onSuccess(messages: List<BaseMessage>) {
      for (messageObj in messages) {
          for (user in messageObj.mentionedUsers) {
              Log.e(TAG, "tag: ${user.tags}")
          }
      }
  }

  override fun onError(e: CometChatException) {
      Log.e(TAG, "onError: " + e)
  }
})

Java

String GUID = "cometchat-guid-1";

MessagesRequest messagesRequest = new MessagesRequest.MessagesRequestBuilder()
.setLimit(50)
.setGUID(GUID)
.mentionsWithTagInfo(true)
.build();

messagesRequest.fetchPrevious(new CometChat.CallbackListener<List<BaseMessage>>() {
  @Override
  public void onSuccess(List<BaseMessage> messages) {
    for (BaseMessage messageObj: messages){
      for (User user: messageObj.getMentionedUsers()){
        Log.e(TAG, "tag: " + user.getTags());
      }
    }
  }

  @Override
  public void onError(CometChatException e) {
    Log.e(TAG, "onError: " + e);
  }
});

Mentions With Blocked Info

To get a list of messages in a conversation where users are mentioned along with the blocked relationship of the mentioned users with the logged-in user.

To User

Kotlin

val UID = "cometchat-uid-1"

val messagesRequest = MessagesRequest.MessagesRequestBuilder()
  .setLimit(50)
  .setUID(UID)
  .mentionsWithBlockedInfo(true)
  .build()

messagesRequest.fetchPrevious(object : CometChat.CallbackListener<List<BaseMessage>>() {
  override fun onSuccess(messages: List<BaseMessage>) {
      for (messageObj in messages) {
          for (user in messageObj.mentionedUsers) {
              Log.e(TAG, "isBlockedByMe: ${user.isBlockedByMe}")
              Log.e(TAG, "isHasBlockedMe: ${user.isHasBlockedMe}")
          }
      }
  }

  override fun onError(e: CometChatException) {
      Log.e(TAG, "onError: " + e)
  }
})

Java

String UID = "cometchat-uid-1";

MessagesRequest messagesRequest = new MessagesRequest.MessagesRequestBuilder()
.setLimit(50)
.setUID(UID)
.mentionsWithBlockedInfo(true)
.build();

messagesRequest.fetchPrevious(new CometChat.CallbackListener<List<BaseMessage>>() {
  @Override
  public void onSuccess(List<BaseMessage> messages) {
    for (BaseMessage messageObj: messages){
      for (User user: messageObj.getMentionedUsers()){
        Log.e(TAG, "isBlockedByMe: " + user.isBlockedByMe());
        Log.e(TAG, "isHasBlockedMe: " + user.isHasBlockedMe());
      }
    }
  }

  @Override
  public void onError(CometChatException e) {
    Log.e(TAG, "onError: " + e);
  }
});

To Group

Kotlin

val GUID = "cometchat-guid-1"

val messagesRequest = MessagesRequest.MessagesRequestBuilder()
  .setLimit(50)
  .setGUID(GUID)
  .mentionsWithBlockedInfo(true)
  .build()

messagesRequest.fetchPrevious(object : CometChat.CallbackListener<List<BaseMessage>>() {
  override fun onSuccess(messages: List<BaseMessage>) {
      for (messageObj in messages) {
          for (user in messageObj.mentionedUsers) {
              Log.e(TAG, "isBlockedByMe: ${user.isBlockedByMe}")
              Log.e(TAG, "isHasBlockedMe: ${user.isHasBlockedMe}")
          }
      }
  }

  override fun onError(e: CometChatException) {
      Log.e(TAG, "onError: " + e)
  }
})

Java

String GUID = "cometchat-guid-1";

MessagesRequest messagesRequest = new MessagesRequest.MessagesRequestBuilder()
.setLimit(50)
.setGUID(GUID)
.mentionsWithBlockedInfo(true)
.build();

messagesRequest.fetchPrevious(new CometChat.CallbackListener<List<BaseMessage>>() {
  @Override
  public void onSuccess(List<BaseMessage> messages) {
    for (BaseMessage messageObj: messages){
      for (User user: messageObj.getMentionedUsers()){
        Log.e(TAG, "isBlockedByMe: " + user.isBlockedByMe());
        Log.e(TAG, "isHasBlockedMe: " + user.isHasBlockedMe());
      }
    }
  }

  @Override
  public void onError(CometChatException e) {
    Log.e(TAG, "onError: " + e);
  }
});

Get Users Mentioned In a Particular Message

To retrieve the list of users mentioned in the particular message, you can use the message.getMentionedUsers() method. This method will return an array containing the mentioned users, or an empty array if no users were mentioned in the message.

Java

message.getMentionedUsers()

Kotlin

message.mentionedUsers

Check if Logged-in user has been mentioned

To check if the logged-in user has been mentioned in a particular message we can use the hasMentionedMe() method on any BaseMessage. This method will return a boolean value, true if the logged-in user has been mentioned, otherwise false.

Kotlin

message.hasMentionedMe

Java

message.hasMentionedMe()

Best Practices

Use Mentions for Important Notifications

Mentions are ideal for drawing attention in group conversations. Use them when you need to ensure specific users see critical messages or action items.

Validate User IDs Before Mentioning

Always verify that the user ID exists before including it in a mention. Invalid UIDs will display as plain text rather than interactive mentions.

Combine with Push Notifications

When a user is mentioned, consider sending a push notification to ensure they’re alerted even when not actively using the app. This enhances engagement and responsiveness.

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Next Steps

Send Messages

Learn how to send text, media, and custom messages

Receive Messages

Handle incoming messages with real-time listeners

Interactive Messages

Create messages with embedded forms and interactive elements

Retrieve Users

Fetch user lists to enable mention autocomplete