我在Xcode中有一个png作为按钮，但是点击png的空白部分并不会触发按钮。我该如何克服这个问题呢？

let button = UIButton(type: .custom)
button.frame = CGRect(x: 0, y: 0, width: image.size.width, height: image.size.height)

button.contentMode = .scaleAspectFit

button.setBackgroundImage(image, for: .normal)

button.setImage(image, for: .normal)

import UIKit

class ViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 加载图片
        if let image = UIImage(named: "yourImageName") {
            // 创建按钮并设置frame
            let button = UIButton(type: .custom)
            button.frame = CGRect(x: 50, y: 100, width: image.size.width, height: image.size.height)
            
            // 设置按钮的contentMode
            button.contentMode = .scaleAspectFit
            
            // 设置按钮的背景图像
            button.setBackgroundImage(image, for: .normal)
            
            // 添加点击事件
            button.addTarget(self, action: #selector(buttonTapped), for: .touchUpInside)
            
            // 将按钮添加到视图中
            view.addSubview(button)
        }
    }
    
    @objc func buttonTapped() {
        print("Button was tapped!")
    }
}