Black background image using camera with Swift2 - swift

Question

I'm trying to display the user camera (back camera) using the AVFoundation, but I must be doing something wrong because It's only showing a black background image.
I have checked my Privacy > Camera and there isn't any option regarding the camera with my App, and I am not able to display the .Alert action to ask the user the permission to access the camera.
Here is my code, I hope you could help me because this is very weird:
import UIKit
import AVFoundation
class CodigoBarrasViewController: UIViewController, AVCaptureMetadataOutputObjectsDelegate {
#IBOutlet weak var messageLabel:UILabel!
#IBOutlet weak var imagenFondo:UIImageView!
#IBOutlet weak var BackgroundView:UIView!
var string:String!
var captureSession:AVCaptureSession?
var videoPreviewLayer:AVCaptureVideoPreviewLayer?
var qrCodeFrameView:UIView?
// Added to support different barcodes
let supportedBarCodes = [AVMetadataObjectTypeQRCode, AVMetadataObjectTypeCode128Code, AVMetadataObjectTypeCode39Code, AVMetadataObjectTypeCode93Code, AVMetadataObjectTypeUPCECode, AVMetadataObjectTypePDF417Code, AVMetadataObjectTypeEAN13Code, AVMetadataObjectTypeAztecCode]
override func viewDidAppear(animated: Bool) {
captureSession?.startRunning()
self.qrCodeFrameView?.hidden = true
}
override func viewDidLoad() {
//captureSession?.startRunning()
super.viewDidLoad()
// Get an instance of the AVCaptureDevice class to initialize a device object and provide the video
// as the media type parameter.
let captureDevice = AVCaptureDevice.defaultDeviceWithMediaType(AVMediaTypeVideo)
do {
input = try AVCaptureDeviceInput(device: captureDevice) as AVCaptureDeviceInput
}
catch let error as NSError {
print(error)
}
// Initialize the captureSession object.
captureSession = AVCaptureSession()
// Set the input device on the capture session.
captureSession?.addInput(input)
//captureSession?.addInput(input as AVCaptureInput)
// Initialize a AVCaptureMetadataOutput object and set it as the output device to the capture session.
let captureMetadataOutput = AVCaptureMetadataOutput()
captureSession?.addOutput(captureMetadataOutput)
// Set delegate and use the default dispatch queue to execute the call back
captureMetadataOutput.setMetadataObjectsDelegate(self, queue: dispatch_get_main_queue())
captureMetadataOutput.metadataObjectTypes = supportedBarCodes
// Initialize the video preview layer and add it as a sublayer to the viewPreview view's layer.
videoPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
videoPreviewLayer?.videoGravity = AVLayerVideoGravityResizeAspectFill
videoPreviewLayer?.frame = view.layer.bounds
view.layer.addSublayer(videoPreviewLayer!)
// Start video capture.
captureSession?.startRunning()
// Move the message label to the top view
view.bringSubviewToFront(imagenFondo)
view.bringSubviewToFront(messageLabel)
view.bringSubviewToFront(BackgroundView)
// Initialize QR Code Frame to highlight the QR code
qrCodeFrameView = UIView()
qrCodeFrameView?.layer.borderColor = UIColor(hex: 0x00B7BB).CGColor
qrCodeFrameView?.layer.borderWidth = 2
view.addSubview(qrCodeFrameView!)
view.bringSubviewToFront(qrCodeFrameView!)
}
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(animated)
//self.navigationController?.hidesBarsOnSwipe = true
self.navigationController?.setNavigationBarHidden(true, animated: false)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func captureOutput(captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [AnyObject]!, fromConnection connection: AVCaptureConnection!) {
// Check if the metadataObjects array is not nil and it contains at least one object.
if metadataObjects == nil || metadataObjects.count == 0 {
qrCodeFrameView?.frame = CGRectZero
//messageLabel.text = "No QR code is detected"
return
}
else
{
// Get the metadata object.
let metadataObj = metadataObjects[0] as! AVMetadataMachineReadableCodeObject
// Here we use filter method to check if the type of metadataObj is supported
// Instead of hardcoding the AVMetadataObjectTypeQRCode, we check if the type
// can be found in the array of supported bar codes.
if supportedBarCodes.filter({ $0 == metadataObj.type }).count > 0 {
// If the found metadata is equal to the QR code metadata then update the status label's text and set the bounds
let barCodeObject = videoPreviewLayer?.transformedMetadataObjectForMetadataObject(metadataObj as AVMetadataMachineReadableCodeObject) as! AVMetadataMachineReadableCodeObject
qrCodeFrameView?.frame = barCodeObject.bounds
if metadataObj.stringValue != nil {
captureSession?.stopRunning()
self.qrCodeFrameView?.hidden = false
launchApp(metadataObj.stringValue)
}
}
}
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
if segue.identifier == "seeProduct" {
let destinationController = segue.destinationViewController as! ProductoCamViewController
let string = (sender as! String!)
let backItem = UIBarButtonItem()
backItem.title = " "
navigationItem.backBarButtonItem = backItem
destinationController.ean = string
}
}
func launchApp(decodedURL: String) {
let alertPrompt = UIAlertController(title: nil, message: nil, preferredStyle: .ActionSheet)
//let alertPrompt = UIAlertController(title: "", message: decodedURL, preferredStyle: .ActionSheet)
let confirmAction = UIAlertAction(title: "See product", style: UIAlertActionStyle.Default, handler: { (action) -> Void in
self.performSegueWithIdentifier("seeProduct", sender: decodedURL)
})
let cancelAction = UIAlertAction(title: "Cancel", style: UIAlertActionStyle.Default, handler: { (action) -> Void in
self.captureSession?.startRunning()
self.qrCodeFrameView?.hidden = true
})
//let cancelAction = UIAlertAction(title: "Cancelar", style: UIAlertActionStyle.Cancel, handler: nil)
alertPrompt.addAction(confirmAction)
alertPrompt.addAction(cancelAction)
self.presentViewController(alertPrompt, animated: true, completion: nil)
}
}
Thanks in advance,
Regards.

Answer 1

I would suggest taking a look at UIImagePickerControllerDelegate if you're wanting to access the camera.
Implement this and all of the permission alerts are handled for you