func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        // Use this method to optionally configure and attach the UIWindow `window` to the provided UIWindowScene `scene`.
        // If using a storyboard, the `window` property will automatically be initialized and attached to the scene.
        // This delegate does not imply the connecting scene or session are new (see `application:configurationForConnectingSceneSession` instead).
        guard let windowScene = (scene as? UIWindowScene) else { return }
        
        #if targetEnvironment(macCatalyst)
        // 固定窗口大小
        //    https://developer.apple.com/forums/thread/117581
        if let sizeRestrictions: UISceneSizeRestrictions = windowScene.sizeRestrictions {
            // iPhone13Pro Max
            windowScene.title = ycScreenTitle
            sizeRestrictions.minimumSize = CGSize(width: ycScreenWidth, height: ycScreenHeight)
            sizeRestrictions.maximumSize = sizeRestrictions.minimumSize
        }
        #endif
}

// keywindow
UIApplication.shared.windows.filter {$0.isKeyWindow}.first

let picker = DocumentPickerViewController(
        supportedTypes: ["log"], 
        onPick: { url in
            print("url : \(url)")
        }, 
        onDismiss: {
            print("dismiss")
        }
    )
    UIApplication.shared.windows.first?.rootViewController?.present(picker, animated: true)

class DocumentPickerViewController: UIDocumentPickerViewController {
    private let onDismiss: () -> Void
    private let onPick: (URL) -> ()

    init(supportedTypes: [String], onPick: @escaping (URL) -> Void, onDismiss: @escaping () -> Void) {
        self.onDismiss = onDismiss
        self.onPick = onPick

        super.init(documentTypes: supportedTypes, in: .open)

        allowsMultipleSelection = false
        delegate = self
    }

    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}

extension DocumentPickerViewController: UIDocumentPickerDelegate {
    func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentsAt urls: [URL]) {
        onPick(urls.first!)
    }

    func documentPickerWasCancelled(_ controller: UIDocumentPickerViewController) {
        onDismiss()
    }
}