update.

Author: cloudwebrtc

example/lib/src/callscreen.dart

@@ -203,14 +203,15 @@ class _MyCallScreenWidget extends State<CallScreenWidget>
     final mediaConstraints = <String, dynamic>{'audio': true, 'video': true};
     MediaStream mediaStream;
 
-    if (kIsWeb) {
+    if (kIsWeb && !voiceonly) {
       mediaStream =
           await navigator.mediaDevices.getDisplayMedia(mediaConstraints);
       mediaConstraints['video'] = false;
       MediaStream userStream =
           await navigator.mediaDevices.getUserMedia(mediaConstraints);
       mediaStream.addTrack(userStream.getAudioTracks()[0], addToNative: true);
     } else {
+      mediaConstraints['video'] = !voiceonly;
       mediaStream = await navigator.mediaDevices.getUserMedia(mediaConstraints);
     }
 

example/lib/src/dialpad.dart

@@ -72,17 +72,18 @@ class _MyDialPadWidget extends State<DialPadWidget>
 
     MediaStream mediaStream;
 
-    if (kIsWeb) {
+    if (kIsWeb && !voiceonly) {
       mediaStream =
           await navigator.mediaDevices.getDisplayMedia(mediaConstraints);
       mediaConstraints['video'] = false;
       MediaStream userStream =
           await navigator.mediaDevices.getUserMedia(mediaConstraints);
       mediaStream.addTrack(userStream.getAudioTracks()[0], addToNative: true);
     } else {
+      mediaConstraints['video'] = !voiceonly;
       mediaStream = await navigator.mediaDevices.getUserMedia(mediaConstraints);
     }
-    
+
     helper.call(dest, voiceonly: voiceonly, mediaStream: mediaStream);
     _preferences.setString('dest', dest);
     return null;