screen sharing.

Author: cloudwebrtc

lib/src/call_sample/call_sample.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'dart:core';
+import '../widgets/screen_select_dialog.dart';
 import 'signaling.dart';
 import 'package:flutter_webrtc/flutter_webrtc.dart';
 
@@ -71,8 +72,7 @@ class _CallSampleState extends State<CallSample> {
             setState(() {
               _inCalling = true;
             });
-          }
-          else {
+          } else {
             _reject();
           }
           break;
@@ -135,15 +135,19 @@ class _CallSampleState extends State<CallSample> {
           title: Text("title"),
           content: Text("accept?"),
           actions: <Widget>[
-            TextButton(
-              child: Text("reject"),
+            MaterialButton(
+              child: Text(
+                'Reject',
+                style: TextStyle(color: Colors.red),
+              ),
               onPressed: () => Navigator.of(context).pop(false),
             ),
-            TextButton(
-              child: Text("accept"),
-              onPressed: () {
-                Navigator.of(context).pop(true);
-              },
+            MaterialButton(
+              child: Text(
+                'Accept',
+                style: TextStyle(color: Colors.green),
+              ),
+              onPressed: () => Navigator.of(context).pop(true),
             ),
           ],
         );
@@ -164,8 +168,7 @@ class _CallSampleState extends State<CallSample> {
               onPressed: () {
                 Navigator.of(context).pop(false);
                 _hangUp();
-                },
-
+              },
             ),
           ],
         );
@@ -201,6 +204,36 @@ class _CallSampleState extends State<CallSample> {
     _signaling?.switchCamera();
   }
 
+  Future<void> selectScreenSourceDialog(BuildContext context) async {
+    final source = await showDialog<DesktopCapturerSource>(
+      context: context,
+      builder: (context) => ScreenSelectDialog(),
+    );
+    if (source != null) {
+      try {
+        var stream =
+            await navigator.mediaDevices.getDisplayMedia(<String, dynamic>{
+          'video': {
+            'deviceId': {'exact': source.id},
+            'mandatory': {'frameRate': 30.0}
+          }
+        });
+        stream.getVideoTracks()[0].onEnded = () {
+          print(
+              'By adding a listener on onEnded you can: 1) catch stop video sharing on Web');
+        };
+        _signaling?.switchToScreenSharing(stream);
+      } catch (e) {
+        print(e);
+      }
+      //await _makeCall(source);
+    }
+  }
+
+  _switchScreenSharing() {
+    //_signaling?.switchToScreenSharing();
+  }
+
   _muteMic() {
     _signaling?.muteMic();
   }
@@ -254,14 +287,20 @@ class _CallSampleState extends State<CallSample> {
       floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,
       floatingActionButton: _inCalling
           ? SizedBox(
-              width: 200.0,
+              width: 240.0,
               child: Row(
                   mainAxisAlignment: MainAxisAlignment.spaceBetween,
                   children: <Widget>[
                     FloatingActionButton(
                       child: const Icon(Icons.switch_camera),
+                      tooltip: 'Camera',
                       onPressed: _switchCamera,
                     ),
+                    FloatingActionButton(
+                      child: const Icon(Icons.desktop_mac),
+                      tooltip: 'Screen Sharing',
+                      onPressed: () => selectScreenSourceDialog(context),
+                    ),
                     FloatingActionButton(
                       onPressed: _hangUp,
                       tooltip: 'Hangup',
@@ -270,6 +309,7 @@ class _CallSampleState extends State<CallSample> {
                     ),
                     FloatingActionButton(
                       child: const Icon(Icons.mic_off),
+                      tooltip: 'Mute Mic',
                       onPressed: _muteMic,
                     )
                   ]))

lib/src/call_sample/signaling.dart

@@ -24,6 +24,11 @@ enum CallState {
   CallStateBye,
 }
 
+enum VideoSource {
+  Camera,
+  Screen,
+}
+
 class Session {
   Session({required this.sid, required this.pid});
   String pid;
@@ -46,6 +51,8 @@ class Signaling {
   Map<String, Session> _sessions = {};
   MediaStream? _localStream;
   List<MediaStream> _remoteStreams = <MediaStream>[];
+  List<RTCRtpSender> _senders = <RTCRtpSender>[];
+  VideoSource videoSource = VideoSource.Camera;
 
   Function(SignalingState state)? onSignalingStateChange;
   Function(Session session, CallState state)? onCallStateChange;
@@ -57,8 +64,7 @@ class Signaling {
       onDataChannelMessage;
   Function(Session session, RTCDataChannel dc)? onDataChannel;
 
-  String get sdpSemantics =>
-      WebRTC.platformIsWindows ? 'plan-b' : 'unified-plan';
+  String get sdpSemantics => 'unified-plan';
 
   Map<String, dynamic> _iceServers = {
     'iceServers': [
@@ -96,10 +102,36 @@ class Signaling {
 
   void switchCamera() {
     if (_localStream != null) {
-      Helper.switchCamera(_localStream!.getVideoTracks()[0]);
+      if (videoSource != VideoSource.Camera) {
+        switchVideoSource(source: VideoSource.Camera);
+        _senders.forEach((sender) {
+          if (sender.track!.kind == 'video') {
+            sender.replaceTrack(_localStream!.getVideoTracks()[0]);
+          }
+        });
+        videoSource = VideoSource.Camera;
+        onLocalStream?.call(_localStream!);
+      } else {
+        Helper.switchCamera(_localStream!.getVideoTracks()[0]);
+      }
     }
   }
 
+  void switchToScreenSharing(MediaStream stream) {
+    if (_localStream != null && videoSource != VideoSource.Screen) {
+      switchVideoSource(source: VideoSource.Screen);
+      _senders.forEach((sender) {
+        if (sender.track!.kind == 'video') {
+          sender.replaceTrack(stream.getVideoTracks()[0]);
+        }
+      });
+      onLocalStream?.call(stream);
+      videoSource = VideoSource.Screen;
+    }
+  }
+
+  void switchVideoSource({VideoSource source = VideoSource.Camera}) {}
+
   void muteMic() {
     if (_localStream != null) {
       bool enabled = _localStream!.getAudioTracks()[0].enabled;
@@ -190,7 +222,6 @@ class Signaling {
             newSession.remoteCandidates.clear();
           }
           onCallStateChange?.call(newSession, CallState.CallStateNew);
-
           onCallStateChange?.call(newSession, CallState.CallStateRinging);
         }
         break;
@@ -356,8 +387,8 @@ class Signaling {
               onAddRemoteStream?.call(newSession, event.streams[0]);
             }
           };
-          _localStream!.getTracks().forEach((track) {
-            pc.addTrack(track, _localStream!);
+          _localStream!.getTracks().forEach((track) async {
+            _senders.add(await pc.addTrack(track, _localStream!));
           });
           break;
       }