Participant Management

CometChat Calling SDK v5 - Beta Release - Participant Management for Flutter

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.

await CallSession.getInstance()?.muteParticipant(participant.uid);

Pause Participant Video

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

await CallSession.getInstance()?.pauseParticipantVideo(participant.uid);

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.

CallSession? callSession = CallSession.getInstance();

// Pin a participant
await callSession?.pinParticipant(participant.uid);

// Unpin (returns to automatic speaker highlighting)
await 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:

CallSession? callSession = CallSession.getInstance();

callSession?.addParticipantEventListener(ParticipantEventListener(
  onParticipantJoined: (Participant participant) {
    debugPrint("${participant.name} joined the call");
    updateParticipantList();
  },
  onParticipantLeft: (Participant participant) {
    debugPrint("${participant.name} left the call");
    updateParticipantList();
  },
  onParticipantListChanged: (List<Participant> participants) {
    debugPrint("Participant count: ${participants.length}");
    refreshParticipantList(participants);
  },
  onParticipantAudioMuted: (Participant participant) {
    debugPrint("${participant.name} was muted");
    updateMuteIndicator(participant, muted: true);
  },
  onParticipantAudioUnmuted: (Participant participant) {
    debugPrint("${participant.name} was unmuted");
    updateMuteIndicator(participant, muted: false);
  },
  onParticipantVideoPaused: (Participant participant) {
    debugPrint("${participant.name} video paused");
    showParticipantAvatar(participant);
  },
  onParticipantVideoResumed: (Participant participant) {
    debugPrint("${participant.name} video resumed");
    showParticipantVideo(participant);
  },
  onDominantSpeakerChanged: (Participant participant) {
    debugPrint("${participant.name} is now speaking");
    highlightActiveSpeaker(participant);
  },
  // Other callbacks...
  onParticipantHandRaised: (Participant participant) {},
  onParticipantHandLowered: (Participant participant) {},
  onParticipantStartedScreenShare: (Participant participant) {},
  onParticipantStoppedScreenShare: (Participant participant) {},
  onParticipantStartedRecording: (Participant participant) {},
  onParticipantStoppedRecording: (Participant participant) {},
));

Flutter listeners are not lifecycle-aware. You must manually remove listeners in your widget’s dispose() method to prevent memory leaks.

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:

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

Participant Actions

Mute, pause video, and pin participants programmatically

Participant Event Listener

Handle all participant events