d

src/V.swift

@@ -13,7 +13,14 @@ struct V: View {
 
       TextField("Binding-3", value: $vm.text, formatter: TextFieldValueOwner())
         .padding(8)
-        .border(Color.green, width: 4)
+        .border(Color.blue, width: 2)
+
+      Button(action: vm.join.send) {
+        Text("Join")
+          .padding(8)
+          .border(vm.isJoinAvailable ? Color.green : Color.red, width: 4)
+      }
+
     }
     .frame(width: 320)
     .padding()