Navigation Bar in Scanner View - IOS - Swift - ios

Question

I want to add to my barcode scanner view the navigation bar. In this way I can close the barcode scanner (modal) view but something doesn't work because the navigation bar isn't here.
These are my setupNavBar method and my navBar to setup my navigationBar:
let navBar: UINavigationBar = {
let bar = UINavigationBar()
bar.translatesAutoresizingMaskIntoConstraints = false
return bar
}()
func setupNavBar(){
view.addSubview(navBar)
view.bringSubview(toFront: navBar)
navBar.heightAnchor.constraint(equalTo: view.heightAnchor, multiplier: 0.09).isActive = true
navBar.widthAnchor.constraint(equalTo: view.widthAnchor).isActive = true
navBar.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
navBar.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
navBar.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
let doneItem = UIBarButtonItem(title:"Cancel",style: .done, target: nil, action: #selector(doneButton));
let navItem = UINavigationItem(title: "Scanner");
navItem.rightBarButtonItem = doneItem;
navBar.setItems([navItem], animated: false);
}
func doneButton(){
let presentingViewController: UIViewController! = self.presentingViewController
presentingViewController.presentingViewController!.dismiss(animated: true, completion: nil)
}
Below this is my code for the scanner:
var captureSession: AVCaptureSession!
var previewLayer: AVCaptureVideoPreviewLayer!
override func viewDidLoad() {
super.viewDidLoad()
setupNavBar()
view.backgroundColor = UIColor.black
captureSession = AVCaptureSession()
let videoCaptureDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo)
let videoInput: AVCaptureDeviceInput
do {
videoInput = try AVCaptureDeviceInput(device: videoCaptureDevice)
} catch {
return
}
if (captureSession.canAddInput(videoInput)) {
captureSession.addInput(videoInput)
} else {
failed();
return;
}
let metadataOutput = AVCaptureMetadataOutput()
if (captureSession.canAddOutput(metadataOutput)) {
captureSession.addOutput(metadataOutput)
metadataOutput.setMetadataObjectsDelegate(self, queue: DispatchQueue.main)
metadataOutput.metadataObjectTypes = [AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypePDF417Code]
} else {
failed()
return
}
previewLayer = AVCaptureVideoPreviewLayer(session: captureSession);
previewLayer.frame = view.layer.bounds;
previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
view.layer.addSublayer(previewLayer);
captureSession.startRunning();
}
func failed() {
let ac = UIAlertController(title: "Scanning not supported", message: "Your device does not support scanning a code from an item. Please use a device with a camera.", preferredStyle: .alert)
ac.addAction(UIAlertAction(title: "OK", style: .default))
present(ac, animated: true)
captureSession = nil
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
if (captureSession?.isRunning == false) {
captureSession.startRunning();
}
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
if (captureSession?.isRunning == true) {
captureSession.stopRunning();
}
}
func captureOutput(_ captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [Any]!, from connection: AVCaptureConnection!) {
captureSession.stopRunning()
if let metadataObject = metadataObjects.first {
let readableObject = metadataObject as! AVMetadataMachineReadableCodeObject;
AudioServicesPlaySystemSound(SystemSoundID(kSystemSoundID_Vibrate))
found(code: readableObject.stringValue);
self.isbn = readableObject.stringValue
self.performSegue(withIdentifier: "scanToSell", sender: nil)
}
}
func found(code: String) {
print(code)
}
override var prefersStatusBarHidden: Bool {
return true
}
override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
return .portrait
}
Thank you in advance. Good Job

Answer 1

I faced the same issue a few days before. I have created a scannerviewcontroller.
Check this: https://gist.github.com/Raghvendra7/ff6335c47bbca04fb88d1cb76917d2e5,
it solved the cancel issue.
Hope it will help.
Working on scanner effect in this controller and will update as it completed.

Answer 2

I have found my error. In my viewDidLoad method the setupNavBar have to change position in this way.
override func viewDidLoad() {
super.viewDidLoad()
// setupNavBar() No
view.backgroundColor = UIColor.black
captureSession = AVCaptureSession()
let videoCaptureDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo)
let videoInput: AVCaptureDeviceInput
do {
videoInput = try AVCaptureDeviceInput(device: videoCaptureDevice)
} catch {
return
}
if (captureSession.canAddInput(videoInput)) {
captureSession.addInput(videoInput)
} else {
failed();
return;
}
let metadataOutput = AVCaptureMetadataOutput()
if (captureSession.canAddOutput(metadataOutput)) {
captureSession.addOutput(metadataOutput)
metadataOutput.setMetadataObjectsDelegate(self, queue: DispatchQueue.main)
metadataOutput.metadataObjectTypes = [AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypePDF417Code]
} else {
failed()
return
}
previewLayer = AVCaptureVideoPreviewLayer(session: captureSession);
previewLayer.frame = view.layer.bounds;
previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
view.layer.addSublayer(previewLayer);
setupNavBar() // Yes
captureSession.startRunning();
}