Ready to implement calls screen

lib/ui/screens/call_screen.dart

@@ -0,0 +1,24 @@
+import 'package:flutter/material.dart';
+
+/// Call screen
+///
+/// @author Pierre Hubert
+
+class CallScreen extends StatefulWidget {
+  final int convID;
+
+  const CallScreen({Key key, @required this.convID})
+      : assert(convID != null),
+        assert(convID > 0),
+        super(key: key);
+
+  @override
+  _CallScreenState createState() => _CallScreenState();
+}
+
+class _CallScreenState extends State<CallScreen> {
+  @override
+  Widget build(BuildContext context) {
+    return Container();
+  }
+}