在ScrollView中隐藏未使用的图像(Swift)

import UIKit

class ViewController: UIViewController {
    @IBOutlet weak var scrollView: UIScrollView!
    var imageViews: [UIImageView] = []
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 添加图像到ScrollView
        for i in 0..<10 {
            let imageView = UIImageView(image: UIImage(named: "image\(i)"))
            imageView.frame = CGRect(x: CGFloat(i) * scrollView.frame.width, y: 0, width: scrollView.frame.width, height: scrollView.frame.height)
            scrollView.addSubview(imageView)
            imageViews.append(imageView)
        }
        
        // 设置ScrollView的contentSize
        scrollView.contentSize = CGSize(width: CGFloat(imageViews.count) * scrollView.frame.width, height: scrollView.frame.height)
        
        // 监听ScrollView的滚动事件
        scrollView.delegate = self
    }
}

extension ViewController: UIScrollViewDelegate {
    func scrollViewDidScroll(_ scrollView: UIScrollView) {
        // 计算可见范围
        let visibleRect = CGRect(x: scrollView.contentOffset.x, y: scrollView.contentOffset.y, width: scrollView.frame.width, height: scrollView.frame.height)
        
        // 遍历所有图像
        for imageView in imageViews {
            // 判断图像的frame是否与可见范围有交集
            if imageView.frame.intersects(visibleRect) {
                // 显示图像
                imageView.isHidden = false
            } else {
                // 隐藏图像
                imageView.isHidden = true
            }
        }
    }
}