Slimming fat viewcontroller - Barcode scanner not working anymore - ios

Question

I have a button on my app that opens upp a barcode scanner, I can then scan an item and it prints the barcode etc.
My Viewcontroller was getting very full of codes, and i just wanted to create another class to seperate and make my code easier to read. So i put all of the barcodescanner code in the class "Partnyallen" and kept my button in class "NewViewController". I can open the barcode, but as soon as i scan an item or even if i press the "cancel" button inside, it just freezes. What could the problem be?
Thankful for any help!
import AVFoundation
import QRCodeReader
import Alamofire
class Partynallen: UIViewController, QRCodeReaderViewControllerDelegate {
lazy var readerVC: QRCodeReaderViewController = {
let builder = QRCodeReaderViewControllerBuilder {
//change object to scan and the initial position of the camera
$0.reader = QRCodeReader(metadataObjectTypes: [.qr, .ean13], captureDevicePosition: .back)
// Configure the view controller (optional)
$0.showTorchButton = true
$0.showSwitchCameraButton = false
$0.showCancelButton = true
$0.showOverlayView = true //shows the square area of the QRCode Scanner
$0.rectOfInterest = CGRect(x: 0, y: 0, width: 1, height: 1)
}
return QRCodeReaderViewController(builder: builder)
}()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
readerVC.delegate = self
}
func reader(_ reader: QRCodeReaderViewController, didScanResult result: QRCodeReaderResult) {
//code to be added
reader.stopScanning()
//print(result)
//print(result.value)
//barcode = result.value
//Apifetch(code: "URL")
dismiss(animated: true, completion: nil)
}
func readerDidCancel(_ reader: QRCodeReaderViewController) {
//code to be added
reader.stopScanning()
dismiss(animated: true, completion: nil)
}
}
class NewViewController: UIViewController {
var partynallen: Partynallen?
override func viewDidLoad() {
super.viewDidLoad()
partynallen = Partynallen() // DONT KNOW IF THIS IS CORRECT?
}
#IBAction func scan(_ sender: UIButton) {
partynallen.readerVC.modalPresentationStyle = .formSheet
present(partynallen.readerVC, animated: true)
}
}

Answer 1

You got 3 ViewControllers NewViewController, QRCodeReaderViewController and Partynallen. But actually you never present Partynallen and just use it as a delegate for the scanner, instead you only present the readerVC. So, when readerDidCancel(:) is called, you try to dismiss Partynallen, which isn’t presented.
Using a ViewController that only acts as the scanner-delegate seems to be a bit too much. You could maybe remove the UIViewController base-class (if it isn‘t required by the scanner-delegate-protocol). And because the delegate-functions, e.g readerDidCancel(:), provide the scanner-vc, you could just use that vc to dismiss itself.