使用AVCaptureSession和AVCaptureVideoPreviewLayer正确地消除视图控制器(以编程方式)

import AVFoundation
import UIKit

let captureSession = AVCaptureSession()
let previewLayer = AVCaptureVideoPreviewLayer(session: captureSession)

guard let videoDevice = AVCaptureDevice.default(for: .video) else { return }
do {
    let videoInput = try AVCaptureDeviceInput(device: videoDevice)
    if captureSession.canAddInput(videoInput) {
        captureSession.addInput(videoInput)
    }
} catch {
    print("Failed to set up video input: \(error)")
}

let videoOutput = AVCaptureVideoDataOutput()
videoOutput.setSampleBufferDelegate(self, queue: DispatchQueue.global(qos: .default))
if captureSession.canAddOutput(videoOutput) {
    captureSession.addOutput(videoOutput)
}

previewLayer.frame = view.bounds
view.layer.addSublayer(previewLayer)

captureSession.startRunning()