Swift:将UIView设置为UIBarButton/UIButton的背景

import UIKit

class CustomButton: UIButton {
    
    override init(frame: CGRect) {
        super.init(frame: frame)
        setupCustomBackground()
    }
    
    required init?(coder: NSCoder) {
        super.init(coder: coder)
        setupCustomBackground()
    }
    
    private func setupCustomBackground() {
        let customView = UIView(frame: bounds)
        customView.backgroundColor = .blue // 设置自定义背景颜色
        layer.insertSublayer(customView.layer, at: 0)
    }
}

// 使用自定义按钮
let button = CustomButton(type: .system)
button.setTitle("Custom Button", for: .normal)
button.frame = CGRect(x: 50, y: 50, width: 200, height: 50)
view.addSubview(button)

let customView = UIView(frame: bounds)
customView.backgroundColor = .blue

let hitAreaButton = UIButton(type: .custom)
hitAreaButton.frame = bounds
hitAreaButton.addTarget(self, action: #selector(buttonTapped), for: .touchUpInside)
customView.addSubview(hitAreaButton)

layer.insertSublayer(customView.layer, at: 0)

@objc private func buttonTapped() {
    print("Button tapped!")
}