Participant ChangeNotifier

lib/src/participant/local_participant.dart

@@ -56,6 +56,7 @@ class LocalParticipant extends Participant {
 
     var pub = new LocalTrackPublication(trackInfo, track, this);
     addTrackPublication(pub);
+    notifyListeners();
 
     return pub;
   }
@@ -83,15 +84,17 @@ class LocalParticipant extends Participant {
 
     var pub = new LocalTrackPublication(trackInfo, track, this);
     addTrackPublication(pub);
+    notifyListeners();
 
     return pub;
   }
 
   unpublishTrack(Track track) {
-    var pub = tracks.values.firstWhere((element) => element.track == track);
-    if (pub == null) {
+    var existing = tracks.values.where((element) => element.track == track);
+    if (existing.isEmpty) {
       return;
     }
+    var pub = existing.first;
 
     track.stop();
     var sender = track.transceiver?.sender;

lib/src/participant/participant.dart

@@ -1,3 +1,5 @@
+import 'package:flutter/foundation.dart';
+
 import 'remote_participant.dart';
 import '../proto/livekit_models.pb.dart';
 import '../track/remote_track_publication.dart';
@@ -22,7 +24,14 @@ mixin ParticipantDelegate {
       RemoteParticipant participant, String sid, String? message) {}
 }
 
-class Participant {
+/// Represents a Participant in the room, notifies changes via delegates as
+/// well as ChangeNotifier/providers.
+/// A change notification is triggered when
+/// - speaking status changed
+/// - mute status changed
+/// - added/removed subscribed tracks
+/// - metadata changed
+class Participant extends ChangeNotifier {
   Map<String, TrackPublication> audioTracks = {};
   Map<String, TrackPublication> videoTracks = {};
 
@@ -45,11 +54,14 @@ class Participant {
   DateTime? lastSpokeAt;
 
   ParticipantDelegate? roomDelegate;
+
+  /// delegate to receive participant callbacks
   ParticipantDelegate? delegate;
 
   ParticipantInfo? _participantInfo;
   bool _isSpeaking = false;
 
+  /// when the participant joined the room
   DateTime get joinedAt {
     var pi = _participantInfo;
     if (pi != null) {
@@ -62,6 +74,30 @@ class Participant {
   /// if participant is currently speaking
   bool get isSpeaking => _isSpeaking;
 
+  /// true if participant is publishing an audio track and is muted
+  bool get isMuted {
+    if (audioTracks.values.isEmpty) {
+      return false;
+    }
+    return audioTracks.values.first.muted;
+  }
+
+  bool get hasAudio => audioTracks.length > 0;
+
+  bool get hasVideo => videoTracks.length > 0;
+
+  /// tracks that are subscribed to
+  List<TrackPublication> get subscribedTracks {
+    List<TrackPublication> result = [];
+    for (var track in tracks.values) {
+      if (track.subscribed) {
+        result.add(track);
+      }
+    }
+    return result;
+  }
+
+  /// internal use
   bool get hasInfo => _participantInfo != null;
 
   Participant(this.sid, this.identity);
@@ -76,6 +112,7 @@ class Participant {
     }
     delegate?.onSpeakingChanged(this, speaking);
     roomDelegate?.onSpeakingChanged(this, speaking);
+    notifyListeners();
   }
 
   _setMetadata(String md) {
@@ -84,6 +121,7 @@ class Participant {
     if (changed) {
       delegate?.onMetadataChanged(this);
       roomDelegate?.onMetadataChanged(this);
+      notifyListeners();
     }
   }
 
@@ -96,6 +134,10 @@ class Participant {
     this._participantInfo = info;
   }
 
+  muteChanged() {
+    notifyListeners();
+  }
+
   addTrackPublication(TrackPublication pub) {
     pub.track?.sid = pub.sid;
     tracks[pub.sid] = pub;

lib/src/participant/remote_participant.dart

@@ -63,6 +63,7 @@ class RemoteParticipant extends Participant {
 
     delegate?.onTrackSubscribed(this, track, pub);
     roomDelegate?.onTrackSubscribed(this, track, pub);
+    notifyListeners();
   }
 
   @override
@@ -95,7 +96,6 @@ class RemoteParticipant extends Participant {
         delegate?.onTrackPublished(this, pub);
         roomDelegate?.onTrackPublished(this, pub);
       }
-      return;
     }
 
     // remove tracks
@@ -120,6 +120,7 @@ class RemoteParticipant extends Participant {
       track.stop();
       delegate?.onTrackUnsubscribed(this, track, pub);
       roomDelegate?.onTrackUnsubscribed(this, track, pub);
+      notifyListeners();
     }
     if (sendUnpublish) {
       delegate?.onTrackUnpublished(this, pub);