Participant Management

Manage participants during a call with actions like muting, pausing video, and pinning. These features help maintain order in group calls and highlight important speakers.

By default, all participants who join a call have moderator access and can perform these actions. Implementing role-based moderation (e.g., restricting actions to hosts only) is the responsibility of the app developer based on their use case.

Mute a Participant

Mute a specific participant’s audio. This affects the participant for all users in the call.

Kotlin

val callSession = CallSession.getInstance()
callSession.muteParticipant(participant.uid)

Java

CallSession callSession = CallSession.getInstance();
callSession.muteParticipant(participant.getUid());

Pause Participant Video

Pause a specific participant’s video. This affects the participant for all users in the call.

Kotlin

val callSession = CallSession.getInstance()
callSession.pauseParticipantVideo(participant.uid)

Java

CallSession callSession = CallSession.getInstance();
callSession.pauseParticipantVideo(participant.getUid());

Pin a Participant

Pin a participant to keep them prominently displayed regardless of who is speaking. Useful for keeping focus on a presenter or important speaker.

Kotlin

val callSession = CallSession.getInstance()

// Pin a participant
callSession.pinParticipant(participant.uid)

// Unpin (returns to automatic speaker highlighting)
callSession.unPinParticipant()

Java

CallSession callSession = CallSession.getInstance();

// Pin a participant
callSession.pinParticipant(participant.getUid());

// Unpin (returns to automatic speaker highlighting)
callSession.unPinParticipant();

Pinning a participant only affects your local view. Other participants can pin different users independently.

Listen for Participant Events

Monitor participant state changes using ParticipantEventListener:

Kotlin

val callSession = CallSession.getInstance()

callSession.addParticipantEventListener(this, object : ParticipantEventListener() {
    override fun onParticipantJoined(participant: Participant) {
        Log.d(TAG, "${participant.name} joined the call")
        updateParticipantList()
    }

    override fun onParticipantLeft(participant: Participant) {
        Log.d(TAG, "${participant.name} left the call")
        updateParticipantList()
    }

    override fun onParticipantListChanged(participants: List<Participant>) {
        Log.d(TAG, "Participant count: ${participants.size}")
        refreshParticipantList(participants)
    }

    override fun onParticipantAudioMuted(participant: Participant) {
        Log.d(TAG, "${participant.name} was muted")
        updateMuteIndicator(participant, muted = true)
    }

    override fun onParticipantAudioUnmuted(participant: Participant) {
        Log.d(TAG, "${participant.name} was unmuted")
        updateMuteIndicator(participant, muted = false)
    }

    override fun onParticipantVideoPaused(participant: Participant) {
        Log.d(TAG, "${participant.name} video paused")
        showParticipantAvatar(participant)
    }

    override fun onParticipantVideoResumed(participant: Participant) {
        Log.d(TAG, "${participant.name} video resumed")
        showParticipantVideo(participant)
    }

    override fun onDominantSpeakerChanged(participant: Participant) {
        Log.d(TAG, "${participant.name} is now speaking")
        highlightActiveSpeaker(participant)
    }

    // Other callbacks...
    override fun onParticipantHandRaised(participant: Participant) {}
    override fun onParticipantHandLowered(participant: Participant) {}
    override fun onParticipantStartedScreenShare(participant: Participant) {}
    override fun onParticipantStoppedScreenShare(participant: Participant) {}
    override fun onParticipantStartedRecording(participant: Participant) {}
    override fun onParticipantStoppedRecording(participant: Participant) {}
})

Java

CallSession callSession = CallSession.getInstance();

callSession.addParticipantEventListener(this, new ParticipantEventListener() {
    @Override
    public void onParticipantJoined(Participant participant) {
        Log.d(TAG, participant.getName() + " joined the call");
        updateParticipantList();
    }

    @Override
    public void onParticipantLeft(Participant participant) {
        Log.d(TAG, participant.getName() + " left the call");
        updateParticipantList();
    }

    @Override
    public void onParticipantListChanged(List<Participant> participants) {
        Log.d(TAG, "Participant count: " + participants.size());
        refreshParticipantList(participants);
    }

    @Override
    public void onParticipantAudioMuted(Participant participant) {
        Log.d(TAG, participant.getName() + " was muted");
        updateMuteIndicator(participant, true);
    }

    @Override
    public void onParticipantAudioUnmuted(Participant participant) {
        Log.d(TAG, participant.getName() + " was unmuted");
        updateMuteIndicator(participant, false);
    }

    @Override
    public void onParticipantVideoPaused(Participant participant) {
        Log.d(TAG, participant.getName() + " video paused");
        showParticipantAvatar(participant);
    }

    @Override
    public void onParticipantVideoResumed(Participant participant) {
        Log.d(TAG, participant.getName() + " video resumed");
        showParticipantVideo(participant);
    }

    @Override
    public void onDominantSpeakerChanged(Participant participant) {
        Log.d(TAG, participant.getName() + " is now speaking");
        highlightActiveSpeaker(participant);
    }

    // Other callbacks...
});

Participant Object

The Participant object contains information about each call participant:

Property	Type	Description
uid	String	Unique identifier (CometChat user ID)
name	String	Display name
avatar	String	URL of avatar image
pid	String	Participant ID for this call session
role	String	Role in the call
audioMuted	Boolean	Whether audio is muted
videoPaused	Boolean	Whether video is paused
isPinned	Boolean	Whether pinned in layout
isPresenting	Boolean	Whether screen sharing
raisedHandTimestamp	Long	Timestamp when hand was raised (0 if not raised)

Hide Participant List Button

To hide the participant list button in the call UI:

Kotlin

val sessionSettings = CometChatCalls.SessionSettingsBuilder()
    .hideParticipantListButton(true)
    .build()

Java

SessionSettings sessionSettings = new CometChatCalls.SessionSettingsBuilder()
    .hideParticipantListButton(true)
    .build();