将向上滑动手势识别器添加到模态视图答案

【问题标题】：Add swipe-up gesture recognizer to a modal view将向上滑动手势识别器添加到模态视图
【发布时间】：2021-07-18 05:39:35
【问题描述】：

我想向以模态方式呈现的视图添加向上滑动识别器。但是，似乎向上滑动和向下滑动手势是为模态呈现的视图中的视图关闭而保留的。当我将识别器设置为识别向左或向右滑动时，它工作得很好，但是当我将它设置为识别向上滑动时，它不起作用。我该如何解决这个问题？

【问题讨论】：

标签： ios swift

【解决方案1】：

添加代理并覆盖手势：

class VC2: UIViewController {
    

    override func viewDidLoad() {
        super.viewDidLoad()
        let direction: UISwipeGestureRecognizer.Direction = .up
        let gesture = UISwipeGestureRecognizer(target: self, action: #selector(swipeAction(sender:)))
        gesture.direction = direction
        gesture.delegate = self
        self.view.addGestureRecognizer(gesture)
    }
    
    @objc func swipeAction(sender: UISwipeGestureRecognizer) {
       print(sender.direction)
     }
}

extension VC2: UIGestureRecognizerDelegate {
    func gestureRecognizerShouldBegin(_ gestureRecognizer: UIGestureRecognizer) -> Bool {
        return true
    }

    func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRequireFailureOf otherGestureRecognizer: UIGestureRecognizer) -> Bool {
        return false
    }

    func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldBeRequiredToFailBy otherGestureRecognizer: UIGestureRecognizer) -> Bool {
        return true
    }

    func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
        return true
    }
}

【讨论】：