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.

Swift

CallSession.shared.muteParticipant(participantId: participant.pid)

Objective-C

[[CallSession shared] muteParticipantWithParticipantId:participant.pid];

Pause Participant Video

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

Swift

CallSession.shared.pauseParticipantVideo(participantId: participant.pid)

Objective-C

[[CallSession shared] pauseParticipantVideoWithParticipantId:participant.pid];

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.

Swift

// Pin a participant
CallSession.shared.pinParticipant()

// Unpin (returns to automatic speaker highlighting)
CallSession.shared.unPinParticipant()

Objective-C

// Pin a participant
[[CallSession shared] pinParticipant];

// Unpin (returns to automatic speaker highlighting)
[[CallSession shared] 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:

Swift

class CallViewController: UIViewController, ParticipantEventListener {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        CallSession.shared.addParticipantEventListener(self)
    }
    
    deinit {
        CallSession.shared.removeParticipantEventListener(self)
    }
    
    func onParticipantJoined(participant: Participant) {
        print("\(participant.name ?? "") joined the call")
        updateParticipantList()
    }

    func onParticipantLeft(participant: Participant) {
        print("\(participant.name ?? "") left the call")
        updateParticipantList()
    }

    func onParticipantListChanged(participants: [Participant]) {
        print("Participant count: \(participants.count)")
        refreshParticipantList(participants)
    }

    func onParticipantAudioMuted(participant: Participant) {
        print("\(participant.name ?? "") was muted")
        updateMuteIndicator(participant, muted: true)
    }

    func onParticipantAudioUnmuted(participant: Participant) {
        print("\(participant.name ?? "") was unmuted")
        updateMuteIndicator(participant, muted: false)
    }

    func onParticipantVideoPaused(participant: Participant) {
        print("\(participant.name ?? "") video paused")
        showParticipantAvatar(participant)
    }

    func onParticipantVideoResumed(participant: Participant) {
        print("\(participant.name ?? "") video resumed")
        showParticipantVideo(participant)
    }

    func onDominantSpeakerChanged(participant: Participant) {
        print("\(participant.name ?? "") is now speaking")
        highlightActiveSpeaker(participant)
    }

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

Objective-C

@interface CallViewController () <ParticipantEventListener>
@end

@implementation CallViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    [[CallSession shared] addParticipantEventListener:self];
}

- (void)dealloc {
    [[CallSession shared] removeParticipantEventListener:self];
}

- (void)onParticipantJoinedWithParticipant:(Participant *)participant {
    NSLog(@"%@ joined the call", participant.name);
    [self updateParticipantList];
}

- (void)onParticipantLeftWithParticipant:(Participant *)participant {
    NSLog(@"%@ left the call", participant.name);
    [self updateParticipantList];
}

- (void)onParticipantListChangedWithParticipants:(NSArray<Participant *> *)participants {
    NSLog(@"Participant count: %lu", (unsigned long)participants.count);
    [self refreshParticipantList:participants];
}

- (void)onParticipantAudioMutedWithParticipant:(Participant *)participant {
    NSLog(@"%@ was muted", participant.name);
}

- (void)onParticipantAudioUnmutedWithParticipant:(Participant *)participant {
    NSLog(@"%@ was unmuted", participant.name);
}

- (void)onDominantSpeakerChangedWithParticipant:(Participant *)participant {
    NSLog(@"%@ is now speaking", participant.name);
}

// Other callbacks...

@end

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	Bool	Whether audio is muted
videoPaused	Bool	Whether video is paused
isPinned	Bool	Whether pinned in layout
isPresenting	Bool	Whether screen sharing
raisedHandTimestamp	Int	Timestamp when hand was raised (0 if not raised)

Hide Participant List Button

To hide the participant list button in the call UI:

Swift

let sessionSettings = CometChatCalls.sessionSettingsBuilder
    .hideParticipantListButton(true)
    .build()

Objective-C

SessionSettings *sessionSettings = [[[CometChatCalls sessionSettingsBuilder]
    hideParticipantListButton:YES]
    build];