{ NavigationView { List(speakersData, id: \.id) { speaker in NavigationLink(destination: SpeakerDetail(speaker: speaker)) { SpeakerRow(speaker: speaker) } } .navigationBarTitle(Text("Speakers"), displayMode: .automatic) } } } #if DEBUG struct SpeakerList_Previews : PreviewProvider { static var previews: some View { Group { SpeakerList() .environment(\.colorScheme, .light) SpeakerList() .environment(\.colorScheme, .dark) } } } #endif public protocol View { associatedtype Body : View var body: Self.Body { get } }