آموزش 21: تکنیک های پیشرفته طرح بندی خودکار برای UI های پاسخگو

let button = UIButton()
button.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(button)
NSLayoutConstraint.activate([
    button.centerXAnchor.constraint(equalTo: view.centerXAnchor),
    button.centerYAnchor.constraint(equalTo: view.centerYAnchor),
    button.widthAnchor.constraint(equalToConstant: 200),
    button.heightAnchor.constraint(equalToConstant: 50)
])

label.setContentHuggingPriority(.defaultHigh, for: .horizontal)
label.setContentCompressionResistancePriority(.defaultLow, for: .horizontal)

if traitCollection.horizontalSizeClass == .regular {
    print("Running on iPad or larger iPhone")
}

label.font = UIFont.preferredFont(forTextStyle: .body)
label.adjustsFontForContentSizeCategory = true

let stackView = UIStackView(arrangedSubviews: [label, button])
stackView.axis = .vertical
stackView.spacing = 10
stackView.distribution = .fillEqually
view.addSubview(stackView)

UIView.animate(withDuration: 0.3) {
    self.buttonConstraint.constant += 50
    self.view.layoutIfNeeded()
}

import ARKit
import UIKit

class LiDARScannerViewController: UIViewController, ARSCNViewDelegate {
    let sceneView = ARSCNView()
    let depthLabel = UILabel()

    override func viewDidLoad() {
        super.viewDidLoad()
        setupSceneView()
        setupDepthLabel()
    }

    func setupSceneView() {
        sceneView.frame = view.bounds
        sceneView.delegate = self
        sceneView.session.run(ARWorldTrackingConfiguration())
        view.addSubview(sceneView)
    }

    func setupDepthLabel() {
        depthLabel.translatesAutoresizingMaskIntoConstraints = false
        depthLabel.text = "Depth: 0m"
        depthLabel.textAlignment = .center
        view.addSubview(depthLabel)

        NSLayoutConstraint.activate([
            depthLabel.centerXAnchor.constraint(equalTo: view.centerXAnchor),
            depthLabel.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor, constant: -20)
        ])
    }

    func renderer(_ renderer: SCNSceneRenderer, updateAtTime time: TimeInterval) {
        guard let frame = sceneView.session.currentFrame else { return }
        if let depthData = frame.sceneDepth?.depthMap {
            let avgDepth = depthData.mean()
            DispatchQueue.main.async {
                self.depthLabel.text = String(format: "Depth: %.2fm", avgDepth)
            }
        }
    }
}

extension CVPixelBuffer {
    func mean() -> Float {
        let width = CVPixelBufferGetWidth(self)
        let height = CVPixelBufferGetHeight(self)
        CVPixelBufferLockBaseAddress(self, .readOnly)
        let buffer = CVPixelBufferGetBaseAddress(self)!
        let sum = (0..<height).reduce(0.0) { (sum, row) -> Float in
            let pixels = buffer.assumingMemoryBound(to: Float.self)
            return sum + pixels[row * width]
        }
        CVPixelBufferUnlockBaseAddress(self, .readOnly)
        return sum / Float(width * height)
    }
}

view.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.deactivate(view.constraints)