当在视图外部点击时，关闭UIView

// 创建一个背景视图
let backgroundView = UIView()
backgroundView.backgroundColor = UIColor.clear

// 将背景视图添加到父视图上
parentView.addSubview(backgroundView)
parentView.sendSubviewToBack(backgroundView)

// 添加手势识别器到背景视图上
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(handleTap(_:)))
backgroundView.addGestureRecognizer(tapGesture)

// 点击事件的处理方法
@objc func handleTap(_ gesture: UITapGestureRecognizer) {
    let tapLocation = gesture.location(in: parentView)
    
    // 判断点击的位置是否在UIView的范围内
    if !view.frame.contains(tapLocation) {
        // 关闭UIView的操作
        view.removeFromSuperview()
    }
}