SwiftUIのライフサイクル

@main
struct SomeApp: App {
    @Environment(\.scenePhase) private var scenePhase
    
    var body: some Scene {
        WindowGroup {
            ContentView()
        }.onChange(of: scenePhase) { (phase) in
            switch phase {
            case .active:
                // The scene is in the foreground and interactive.
            case .background:
                // The scene isn’t currently visible in the UI.
            case .inactive:
                // The scene is in the foreground but should pause its work.
            @unknown default:
                fatalError()
            }
        }
    }
}