revert changes.

example/lib/pages/room.dart

@@ -32,6 +32,8 @@ class _RoomPageState extends State<RoomPage> {
   @override
   void initState() {
     super.initState();
+    // add callback for a `RoomEvent` as opposed to a `ParticipantEvent`
+    widget.room.addListener(_onRoomDidUpdate);
     // add callbacks for finer grained events
     _setUpListeners();
     _sortParticipants();
@@ -50,6 +52,7 @@ class _RoomPageState extends State<RoomPage> {
   void dispose() {
     // always dispose listener
     (() async {
+      widget.room.removeListener(_onRoomDidUpdate);
       await _listener.dispose();
       await widget.room.dispose();
     })();
@@ -65,13 +68,16 @@ class _RoomPageState extends State<RoomPage> {
       WidgetsBindingCompatible.instance
           ?.addPostFrameCallback((timeStamp) => Navigator.pop(context));
     })
+    ..on<ParticipantEvent>((event) {
+      print('Participant event');
+      // sort participants on many track events as noted in documentation linked above
+      _sortParticipants();
+    })
     ..on<RoomRecordingStatusChanged>((event) {
       context.showRecordingStatusChangedDialog(event.activeRecording);
     })
     ..on<LocalTrackPublishedEvent>((_) => _sortParticipants())
     ..on<LocalTrackUnpublishedEvent>((_) => _sortParticipants())
-    ..on<TrackSubscribedEvent>((_) => _sortParticipants())
-    ..on<TrackUnsubscribedEvent>((_) => _sortParticipants())
     ..on<TrackE2EEStateEvent>(_onE2EEStateEvent)
     ..on<ParticipantNameUpdatedEvent>((event) {
       print(
@@ -114,6 +120,10 @@ class _RoomPageState extends State<RoomPage> {
     }
   }
 
+  void _onRoomDidUpdate() {
+    _sortParticipants();
+  }
+
   void _onE2EEStateEvent(TrackE2EEStateEvent e2eeState) {
     print('e2ee state: $e2eeState');
   }

example/lib/widgets/video_widget.dart

@@ -0,0 +1,32 @@
+import 'package:flutter/material.dart';
+import 'package:livekit_client/livekit_client.dart';
+import 'package:flutter_webrtc/flutter_webrtc.dart';
+import 'dart:math' as math;
+
+import 'package:livekit_example/theme.dart';
+
+class VideoWidget extends StatelessWidget {
+  final VideoTrack? track;
+  final RTCVideoRenderer renderer;
+  bool get hasVideo => track != null && !(track?.muted ?? true);
+  const VideoWidget(this.renderer, this.track, {Key? key}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) => hasVideo
+      ? VideoTrackRenderer(
+          key: ValueKey(track!.sid),
+          renderer,
+          track!,
+          fit: RTCVideoViewObjectFit.RTCVideoViewObjectFitContain,
+        )
+      : Container(
+          alignment: Alignment.center,
+          child: LayoutBuilder(
+            builder: (ctx, constraints) => Icon(
+              Icons.videocam_off_outlined,
+              color: LKColors.lkBlue,
+              size: math.min(constraints.maxHeight, constraints.maxWidth) * 0.3,
+            ),
+          ),
+        );
+}