如何禁用UIScrollView到平移手势识别器？

Question

当平局手势识别器被称为SomePanGestureRecognizer时，如何禁用或强制手势识别器在UIScrollView中失败？

gestureRecognizer(_:shouldBeRequiredToFailBy:)方法需要一个手势识别器参数，而不是一个平移手势识别器，我不知道这是为什么我不能让它工作或因为我犯了一个语法错误。

我有UIScrollView子类，而用于强制方法失败是在下面的委托：

class CustomScrollView: UIScrollView { 

    override init(frame: CGRect) { 
     super.init(frame: frame) 

     configure() 

    } 

    required init?(coder aDecoder: NSCoder) { 
     super.init(coder: aDecoder) 

     configure() 

    } 

    private func configure() { 

     isScrollEnabled = true 
     showsHorizontalScrollIndicator = false 
     showsVerticalScrollIndicator = false 
     isPagingEnabled = true 
     bounces = false 
     alwaysBounceVertical = false 
     alwaysBounceHorizontal = false 

    } 

} 

// gesture recognizer delegate 
extension CustomScrollView: UIGestureRecognizerDelegate { 

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

    // force failure 
    func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldBeRequiredToFailBy otherGestureRecognizer: UIGestureRecognizer) -> Bool { 

     // TLDR: disable uiscrollview when SomePanGestureRecognizer is called 

    } 

} 

这里是一个需要给力的UIScrollView手势识别失败泛手势识别：

func addSomePanGestureRecognizer() { 
    SomePanGestureRecognizer = UIPanGestureRecognizer(target: self, action: #selector(oneBPanGestureHandler(gesture:))) 
    oneBHandle.addGestureRecognizer(SomePanGestureRecognizer) 
} 

UPDATE我将UIPanGestureRecognizer子类化并使用同时委托来工作，但我担心这是一种不稳定的方式，因为我依靠UIKit始终在自定义平移手势之前禁用UIScrollView。

// gesture recognizer delegate 
extension CustomScrollView: UIGestureRecognizerDelegate { 

    // simultaneous gestures 
    func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool { 

     if otherGestureRecognizer is CustomPanGestureRecognizer { 
      return false 
     } else { 
      return true 
     } 

    } 

} 

更新2这也适用，但我不知道为什么，因为我觉得它不应该。难道不是相反吗？

// force failure 
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRequireFailureOf otherGestureRecognizer: UIGestureRecognizer) -> Bool { 

    if otherGestureRecognizer is CustomPanGestureRecognizer { 
     return true 
    } else { 
     return false 
    } 

} 

Answer 1

我相信这是你在找什么：

func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool { 
    let isPanAndOtherRecognizer = gestureRecognizer is UIPanGestureRecognizer && otherGestureRecognizer is SomePanGestureRecognizer 
    return !isPanAndOtherRecognizer 
} 

// force failure 
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldBeRequiredToFailBy otherGestureRecognizer: UIGestureRecognizer) -> Bool { 

    let isPanAndOtherRecognizer = gestureRecognizer is UIPanGestureRecognizer && otherGestureRecognizer is SomePanGestureRecognizer 
    return isPanAndOtherRecognizer 
}