Can toggle local stream visibility

lib/ui/screens/call_screen.dart

@@ -46,6 +46,7 @@ class _CallScreenState extends SafeState<CallScreen> {
   final _peersConnections = Map<int, RTCPeerConnection>();
   final _renderers = Map<int, RTCVideoRenderer>();
   MediaStream _localStream;
+  var _isLocalStreamVisible = true;
 
   bool get _canMakeVideoCall =>
       _conversation.callCapabilities == CallCapabilities.VIDEO;
@@ -337,6 +338,13 @@ class _CallScreenState extends SafeState<CallScreen> {
     setState(() {});
   }
 
+  /// Toggle local stream visibility
+  void _toggleLocalStreamVisibility() {
+    setState(() {
+      _isLocalStreamVisible = !_isLocalStreamVisible;
+    });
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
@@ -409,7 +417,9 @@ class _CallScreenState extends SafeState<CallScreen> {
         ),
 
         // Local peer video
-        isStreamingVideo ? _buildLocalVideo() : Container(),
+        isStreamingVideo && _isLocalStreamVisible
+            ? _buildLocalVideo()
+            : Container(),
       ],
     ));
   }
@@ -435,6 +445,14 @@ class _CallScreenState extends SafeState<CallScreen> {
       child: Row(
         mainAxisAlignment: MainAxisAlignment.center,
         children: <Widget>[
+          // Show / hide user video button
+          _FooterButton(
+            icon: Icon(_isLocalStreamVisible
+                ? Icons.visibility
+                : Icons.visibility_off),
+            onPressed: () => _toggleLocalStreamVisibility(),
+          ),
+
           // Toggle audio button
           _FooterButton(
             onPressed: () => _toggleStreaming(false),
@@ -467,8 +485,8 @@ class _FooterButton extends StatelessWidget {
 
   const _FooterButton({
     Key key,
-    @required this.onPressed,
     @required this.icon,
+    @required this.onPressed,
   })  : assert(onPressed != null),
         assert(icon != null),
         super(key: key);