如何在UIAlertController中添加图像拾取器

import UIKit

class ViewController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
    
    override func viewDidLoad() {
        super.viewDidLoad()
    }
    
    func presentImagePicker() {
        let alertController = UIAlertController(title: "选择图片", message: nil, preferredStyle: .actionSheet)
        
        let imagePicker = UIImagePickerController()
        imagePicker.delegate = self
        imagePicker.sourceType = .photoLibrary
        
        let selectAction = UIAlertAction(title: "从相册选择", style: .default) { (action) in
            self.present(imagePicker, animated: true, completion: nil)
        }
        
        let cancelAction = UIAlertAction(title: "取消", style: .cancel, handler: nil)
        
        alertController.addAction(selectAction)
        alertController.addAction(cancelAction)
        
        present(alertController, animated: true, completion: nil)
    }
    
    // UIImagePickerControllerDelegate方法，获取用户选择的图像
    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
        if let image = info[UIImagePickerController.InfoKey.originalImage] as? UIImage {
            // 在这里可以对选择的图像进行处理
        }
        
        dismiss(animated: true, completion: nil)
    }
}