扫描所有类型的条形码

Question

我遵循了各种SO答案以及此博客https://github.com/appcoda/QRCodeReader/blob/master/QRCodeReader/QRScannerController.swift？但问题是它只扫描一种类型的条形码“AVMetadataObject.ObjectType.code128”。

func metadataOutput(_ output: AVCaptureMetadataOutput, didOutput metadataObjects: [AVMetadataObject], from connection: AVCaptureConnection) {
    let barCodeTypes = [AVMetadataObject.ObjectType.upce,AVMetadataObject.ObjectType.code39,AVMetadataObject.ObjectType.code39Mod43, AVMetadataObject.ObjectType.ean13,AVMetadataObject.ObjectType.ean8,AVMetadataObject.ObjectType.code93, AVMetadataObject.ObjectType.code128,AVMetadataObject.ObjectType.pdf417,AVMetadataObject.ObjectType.qr, AVMetadataObject.ObjectType.aztec]

    // Check if the metadataObjects array is not nil and it contains at least one object.
    if metadataObjects.count == 0 {
        print("No Barcode is detected")
        return
    }
    // Get the metadata object.
    let metadataObj = metadataObjects[0] as! AVMetadataMachineReadableCodeObject

    if barCodeTypes.contains(metadataObj.type) {
        // If the found metadata is equal to the QR code metadata then update the status label's text and set the bounds
        _ = video.transformedMetadataObject(for: metadataObj)

        if metadataObj.stringValue != nil {
            let alert = UIAlertController(title: "Barcode", message: metadataObj.stringValue, preferredStyle: .alert)
            alert.addAction(UIAlertAction(title: "Retake", style: .default, handler: nil))
            alert.addAction(UIAlertAction(title: "Copy", style: .default, handler: {(nil) in UIPasteboard.general.string = metadataObj.stringValue
                self.barCode_Generation(barCodeValue: metadataObj.stringValue!)
            }))
            present(alert, animated: true, completion: nil)
            print(metadataObj.stringValue!)
        }
    }
}