Mentions Formatter

Format and style @mentions in messages with customizable appearance and click handling.

AI Agent Component Spec

Field	Value
Package	com.cometchat.chatuikit.shared.formatters
Key class	CometChatMentionsFormatter (extends CometChatTextFormatter)
Required setup	CometChatUIKit.init() then CometChatUIKit.login("UID")
Purpose	Format @mentions with styled tokens, suggestion list, and click handling for users and group members
Sample app	GitHub
Related	ShortCut Formatter | All Guides

CometChatMentionsFormatter extends CometChatTextFormatter to format @mentions in text messages. It styles mention tokens, generates suggestion lists as users type, and handles click events on rendered mentions across the message composer, message bubbles, and conversations list.

Capability	Description
Mention formatting	Auto-formats mention placeholders into styled spans
Custom styles	Colors, fonts, and backgrounds per context (composer, bubbles, conversations)
User and group mentions	Works with both individual users and group members
Suggestion list	Generates mention candidates from user input
Click handling	Listener interface for tap on rendered mentions

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Usage

1. Create the formatter

Kotlin

val mentionFormatter = CometChatMentionsFormatter(context)

Java

CometChatMentionsFormatter mentionFormatter = new CometChatMentionsFormatter(context);

2. Add to a formatters list

Kotlin

val textFormatters: MutableList<CometChatTextFormatter> = ArrayList()
textFormatters.add(mentionFormatter)

Java

List<CometChatTextFormatter> textFormatters = new ArrayList<>();
textFormatters.add(mentionFormatter);

3. Pass to a component

Use setTextFormatters() on CometChatMessageComposer, CometChatMessageList, or CometChatConversations.

Kotlin

messageComposer.setTextFormatters(textFormatters)

Java

messageComposer.setTextFormatters(textFormatters);

---

Styling Mentions

Mention Click Handling

Set a click listener for mentions in message bubbles:

Kotlin

val mentionFormatter = CometChatMentionsFormatter(context)

mentionFormatter.setOnMentionClick { context, user ->
    Toast.makeText(context, user.name, Toast.LENGTH_SHORT).show()
}

val textFormatters: MutableList<CometChatTextFormatter> = ArrayList()
textFormatters.add(mentionFormatter)
messageComposer.setTextFormatters(textFormatters)

Java

CometChatMentionsFormatter mentionFormatter = new CometChatMentionsFormatter(context);

mentionFormatter.setOnMentionClick((context, user) -> {
    Toast.makeText(context, user.getName(), Toast.LENGTH_SHORT).show();
});

List<CometChatTextFormatter> textFormatters = new ArrayList<>();
textFormatters.add(mentionFormatter);
messageComposer.setTextFormatters(textFormatters);

Composer Mention Style

Customize how mentions appear in the message composer input field:

themes.xml

<style name="CustomMessageComposerMentionsStyle" parent="CometChatMessageComposerMentionsStyle">
    <item name="cometchatMentionTextAppearance">?attr/cometchatTextAppearanceBodyRegular</item>
    <item name="cometchatMentionTextColor">#000000</item>
    <item name="cometchatMentionBackgroundColor">#000000</item>
    <item name="cometchatSelfMentionTextColor">#30A46C</item>
    <item name="cometchatSelfMentionTextAppearance">?attr/cometchatTextAppearanceBodyRegular</item>
    <item name="cometchatSelfMentionBackgroundColor">#30A46C</item>
</style>

Kotlin

val mentionFormatter = CometChatMentionsFormatter(context)
mentionFormatter.setMessageComposerMentionTextStyle(context, R.style.CustomMessageComposerMentionsStyle)

val textFormatters: MutableList<CometChatTextFormatter> = ArrayList()
textFormatters.add(mentionFormatter)
messageComposer.setTextFormatters(textFormatters)

Java

CometChatMentionsFormatter mentionFormatter = new CometChatMentionsFormatter(context);
mentionFormatter.setMessageComposerMentionTextStyle(context, R.style.CustomMessageComposerMentionsStyle);

List<CometChatTextFormatter> textFormatters = new ArrayList<>();
textFormatters.add(mentionFormatter);
messageComposer.setTextFormatters(textFormatters);

Message Bubble Mention Style

Customize mentions in incoming and outgoing message bubbles:

themes.xml

<style name="CustomIncomingMessageBubbleMentionStyle" parent="CometChatIncomingBubbleMentionsStyle">
    <item name="cometchatMentionTextAppearance">?attr/cometchatTextAppearanceBodyRegular</item>
    <item name="cometchatMentionTextColor">#D6409F</item>
    <item name="cometchatMentionBackgroundColor">#D6409F</item>
    <item name="cometchatSelfMentionTextColor">#30A46C</item>
    <item name="cometchatSelfMentionTextAppearance">?attr/cometchatTextAppearanceBodyRegular</item>
    <item name="cometchatSelfMentionBackgroundColor">#30A46C</item>
</style>

<style name="CustomOutgoingMessageBubbleMentionStyle" parent="CometChatOutgoingBubbleMentionsStyle">
    <item name="cometchatMentionTextAppearance">?attr/cometchatTextAppearanceBodyRegular</item>
    <item name="cometchatMentionTextColor">#FFFFFF</item>
    <item name="cometchatMentionBackgroundColor">#F9F8FD</item>
    <item name="cometchatSelfMentionTextColor">#30A46C</item>
    <item name="cometchatSelfMentionTextAppearance">?attr/cometchatTextAppearanceBodyRegular</item>
    <item name="cometchatSelfMentionBackgroundColor">#30A46C</item>
</style>

Kotlin

val mentionFormatter = CometChatMentionsFormatter(context)
mentionFormatter.setOutgoingBubbleMentionTextStyle(context, R.style.CustomOutgoingMessageBubbleMentionStyle)
mentionFormatter.setIncomingBubbleMentionTextStyle(context, R.style.CustomIncomingMessageBubbleMentionStyle)

val textFormatters: MutableList<CometChatTextFormatter> = ArrayList()
textFormatters.add(mentionFormatter)
messageList.setTextFormatters(textFormatters)

Java

CometChatMentionsFormatter mentionFormatter = new CometChatMentionsFormatter(context);
mentionFormatter.setOutgoingBubbleMentionTextStyle(context, R.style.CustomOutgoingMessageBubbleMentionStyle);
mentionFormatter.setIncomingBubbleMentionTextStyle(context, R.style.CustomIncomingMessageBubbleMentionStyle);

List<CometChatTextFormatter> textFormatters = new ArrayList<>();
textFormatters.add(mentionFormatter);
messageList.setTextFormatters(textFormatters);

Conversations Mention Style

Customize mentions in the conversations list last-message preview:

themes.xml

<style name="CustomConversationsMentionsStyle" parent="CometChatConversationsMentionsStyle">
    <item name="cometchatMentionTextAppearance">?attr/cometchatTextAppearanceBodyRegular</item>
    <item name="cometchatMentionTextColor">#D6409F</item>
    <item name="cometchatMentionBackgroundColor">#D6409F</item>
    <item name="cometchatSelfMentionTextColor">#30A46C</item>
    <item name="cometchatSelfMentionTextAppearance">?attr/cometchatTextAppearanceBodyRegular</item>
    <item name="cometchatSelfMentionBackgroundColor">#30A46C</item>
</style>

Kotlin

val mentionFormatter = CometChatMentionsFormatter(context)
mentionFormatter.setConversationsMentionTextStyle(context, R.style.CustomConversationsMentionsStyle)

val textFormatters: MutableList<CometChatTextFormatter> = ArrayList()
textFormatters.add(mentionFormatter)
cometChatConversations.setTextFormatters(textFormatters)

Java

CometChatMentionsFormatter mentionFormatter = new CometChatMentionsFormatter(context);
mentionFormatter.setConversationsMentionTextStyle(context, R.style.CustomConversationsMentionsStyle);

List<CometChatTextFormatter> textFormatters = new ArrayList<>();
textFormatters.add(mentionFormatter);
cometChatConversations.setTextFormatters(textFormatters);

---

Customization Matrix

What you want to change	Where	Property/API	Example
Maximum number of mentions allowed	CometChatMentionsFormatter	setMentionLimit(int limit)	mentionFormatter.setMentionLimit(5)
Group members fetched for mention suggestions	CometChatMentionsFormatter	.setGroupMembersRequestBuilder(...)	.setGroupMembersRequestBuilder(group -> new GroupMembersRequest.GroupMembersRequestBuilder(group.getGuid()));
Users fetched for mention suggestions	CometChatMentionsFormatter	.setUsersRequestBuilder(...)	.setUsersRequestBuilder(new UsersRequest.UsersRequestBuilder().friendsOnly(true));
Who can be mentioned	CometChatMentionsFormatter	.setMentionsType(...)	.setMentionsType(UIKitConstants.MentionsType.USERS_AND_GROUP_MEMBERS)
Where mentions are visible	CometChatMentionsFormatter	.setMentionsVisibility(...)	.setMentionsVisibility(UIKitConstants.MentionsVisibility.BOTH);
Click action on a mention	CometChatMentionsFormatter	setOnMentionClick	mentionFormatter.setOnMentionClick((context, user) -> { });
Mention text style in composer	CometChatMentionsFormatter	setMessageComposerMentionTextStyle(context, styleRes)	mentionFormatter.setMessageComposerMentionTextStyle(context, R.style.CustomStyle)
Mention text style in outgoing bubbles	CometChatMentionsFormatter	setOutgoingBubbleMentionTextStyle(context, styleRes)	mentionFormatter.setOutgoingBubbleMentionTextStyle(context, R.style.CustomStyle)
Mention text style in incoming bubbles	CometChatMentionsFormatter	setIncomingBubbleMentionTextStyle(context, styleRes)	mentionFormatter.setIncomingBubbleMentionTextStyle(context, R.style.CustomStyle)
Mention text style in conversations list	CometChatMentionsFormatter	setConversationsMentionTextStyle(context, styleRes)	mentionFormatter.setConversationsMentionTextStyle(context, R.style.CustomStyle)

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Next Steps

Message Composer

Configure the composer where users type and send messages with mentions

Message List

Configure the message list where mention-styled bubbles are displayed

Conversations

Configure the conversations list where mention-styled previews appear

ShortCut Formatter

Add shortcut text expansion to the message composer