Ios 成功扫描后停止AVF

我正在为iOS 10构建一个带有Swift 3（Xcode 8.1）的二维码扫描应用程序，我正在使用AVFoundation框架。有人知道如何在成功扫描后停止扫描，并在点击屏幕或其他东西后重新启动扫描仪吗

编辑： 下面是我的代码片段（没有关于返回值的代码）：

---

在委托方法中尝试此操作

func captureOutput(_ captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [Any]!, from connection: AVCaptureConnection!) {

if metadataObjects == nil || metadataObjects.count == 0 {
    qrCodeFrameView?.frame = CGRect.zero
    return
}

let metadataObj = metadataObjects[0] as! AVMetadataMachineReadableCodeObject


if supportedBarCodes.contains(metadataObj.type) {

    let barCodeObject = videoPreviewLayer?.transformedMetadataObject(for: metadataObj)
    qrCodeFrameView?.frame = barCodeObject!.bounds
    print(metadataObj.stringValue)

    // Stop capture session 
    videoPreviewLayer?.isHidden = true
    qrCodeFrameView?.isHidden = true
    self.captureSession?.stopRunning()
}

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您能分享一些代码吗？@MuseerAnsari在问题中添加了代码。请检查我的答案，如果您有任何问题，请告诉我，谢谢！欢迎并祝您愉快：）

func captureOutput(_ captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [Any]!, from connection: AVCaptureConnection!) {

if metadataObjects == nil || metadataObjects.count == 0 {
    qrCodeFrameView?.frame = CGRect.zero
    return
}

let metadataObj = metadataObjects[0] as! AVMetadataMachineReadableCodeObject


if supportedBarCodes.contains(metadataObj.type) {

    let barCodeObject = videoPreviewLayer?.transformedMetadataObject(for: metadataObj)
    qrCodeFrameView?.frame = barCodeObject!.bounds
    print(metadataObj.stringValue)

    // Stop capture session 
    videoPreviewLayer?.isHidden = true
    qrCodeFrameView?.isHidden = true
    self.captureSession?.stopRunning()
}