Camera preview layer makes button invisible - ios

Question

I'm trying to add a button over a camera preview but it doesn't show up when I run the program (I have constraints). I looked into the code and tried to debug but I'm new to swift and Xcode and I'm new to debugging in general. I saw that when I commented out the camera preview layer the button showed up. Thanks!
import UIKit
import AVFoundation
import QuartzCore
class View1: UIViewController , AVCaptureVideoDataOutputSampleBufferDelegate{
let captureSession = AVCaptureSession()
var previewLayer:CALayer!
var captureDevice:AVCaptureDevice!
#IBOutlet weak var cameraView:UIView!
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
prepareCamera()
}
func prepareCamera() {
captureSession.sessionPreset = AVCaptureSessionPreset1920x1080
if let availableDevices = AVCaptureDeviceDiscoverySession(deviceTypes: [.builtInWideAngleCamera], mediaType: AVMediaTypeVideo, position: .back).devices {
captureDevice = availableDevices.first
beginSession()
}
}
func beginSession() {
do {
let captureDeviceInput = try AVCaptureDeviceInput(device: captureDevice)
captureSession.addInput(captureDeviceInput)
} catch {
print(error.localizedDescription)
//Figure out what to do here
}
if let previewLayer = AVCaptureVideoPreviewLayer(session: captureSession) {
self.previewLayer = previewLayer
self.view.layer.addSublayer(self.previewLayer)
self.previewLayer.frame = self.view.layer.frame
captureSession.startRunning()
let dataOutput = AVCaptureVideoDataOutput()
dataOutput.videoSettings = [(kCVPixelBufferPixelFormatTypeKey as NSString): NSNumber(value: kCVPixelFormatType_32BGRA)]
dataOutput.alwaysDiscardsLateVideoFrames = true
if captureSession.canAddOutput(dataOutput){
captureSession.addOutput(dataOutput)
captureSession.commitConfiguration()
}
let queue = DispatchQueue(label: "com.PhotoAllergy.captureQueue")
dataOutput.setSampleBufferDelegate(self, queue: queue)
}
}
}

Answer 1

Maybe you could try setting the zPosition of the button to 1 or higher. YourButtonName.layer.zPostion = 2
Apple Documentation on ZPosition

Answer 2

You just have to add button as subview to view that is working as a preview for your avcamera.
class RecordVC {
#IBOutlet weak var vwRecordVideo : UIView!
#IBOutlet weak var btnGallary : UIButton!
override func viewDidLoad() {
super.viewDidLoad()
vwRecordVideo.addSubview(cameraButton)
vwRecordVideo.addSubview(btnGallary)
}
}