Swift中为DataScannerViewController设置扫描框并限制16位PIN码识别

我需要将相机扫描器限制为仅读取16位PIN码，效果类似其他应用的横向窄条扫描框。

已尝试的无效方案： #

• 设置recognizedDataTypes: [.text(textContentType: .telephoneNumber)]：未显示扫描框，且最多只能识别14位数字（我需要16位）
• 为视图控制器添加regionOfInterest：无任何变化，代码片段：

  let viewController = DataScannerViewController(...)
  viewController.regionOfInterest = CGRect(x: 0, y: 0, width: 200, height: 300)
  viewController.delegate = context.coordinator
  return viewController
  

• 尝试设置视图控制器的frame：无效果，代码片段：

  let frame = CGRect(x: 0, y:0, width: 200, height: 300)
  viewController.view.frame = frame
  

完整代码： #

struct CameraScannerViewController: UIViewControllerRepresentable {

@Binding var startScanning: Bool
@Binding var scanResult: String

func makeCoordinator() -> Coordinator {
    Coordinator(self)
}

func makeUIViewController(context: Context) -> DataScannerViewController {
    let frame = CGRect(x: 0, y: 0, width: 200, height: 300)
    let viewController = DataScannerViewController(
        recognizedDataTypes: [.text(textContentType: .telephoneNumber)],
        qualityLevel: .fast,
        recognizesMultipleItems: false,
        isHighFrameRateTrackingEnabled: false,
        isHighlightingEnabled: true)
    //viewController.view.frame = frame
    //viewController.regionOfInterest = CGRect(x: 0, y: 0, width: 200, height: 300)
    viewController.delegate = context.coordinator
    return viewController
}

func updateUIViewController(_ viewController: DataScannerViewController, context: Context) {
    if startScanning{
        try? viewController.startScanning()
    }else {
        viewController.stopScanning()
    }
}

class Coordinator: NSObject, DataScannerViewControllerDelegate {
    var parent: CameraScannerViewController
    init(_ parent: CameraScannerViewController){
        self.parent = parent
    }
    
    func dataScanner(_ dataScanner: DataScannerViewController, didTapOn item: RecognizedItem) {
        switch item {
        case .text(let text):
            parent.scanResult = text.transcript
            dataScanner.stopScanning()
            dataScanner.dismiss(animated: true)
        default:
            break
        }
    }
}

内容的提问来源于stack exchange，提问作者KiDo