自定义胶囊背景与UIImageView编程不工作？

import UIKit

class ViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 创建UIImageView
        let imageView = UIImageView(image: UIImage(named: "yourImage"))
        imageView.frame = CGRect(x: 50, y: 50, width: 200, height: 200)
        imageView.contentMode = .scaleAspectFit
        
        // 创建胶囊背景
        let capsuleBackgroundView = UIView(frame: imageView.frame)
        capsuleBackgroundView.backgroundColor = .blue
        capsuleBackgroundView.layer.cornerRadius = imageView.frame.height / 2
        capsuleBackgroundView.clipsToBounds = true
        
        // 将UIImageView添加到胶囊背景视图上
        capsuleBackgroundView.addSubview(imageView)
        
        // 将胶囊背景视图添加到当前视图
        view.addSubview(capsuleBackgroundView)
    }
}