檢索挖掘的UIButton在正在運行的動畫，可以稍微偏離屏幕

Question

這是代碼（見下文）可以是什麼樣子：

代碼：

import UIKit 

class TornadoButton: UIButton{ 
override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? { 
    let pres = self.layer.presentation()! 
    let suppt = self.convert(point, to: self.superview!) 
    let prespt = self.superview!.layer.convert(suppt, to: pres) 
    return super.hitTest(prespt, with: event) 
} 
} 

class TestViewController: UIViewController{ 
    override func viewDidAppear(_ animated: Bool) { 
     super.viewDidAppear(animated) 
     let greySubview = UIView() 
     greySubview.backgroundColor = .red 
     greySubview.translatesAutoresizingMaskIntoConstraints = false 
     self.view.addSubview(greySubview) 
     greySubview.centerXAnchor.constraint(equalTo: self.view.centerXAnchor).isActive = true 
     greySubview.centerYAnchor.constraint(equalTo: self.view.centerYAnchor).isActive = true 
     greySubview.widthAnchor.constraint(equalTo: self.view.widthAnchor).isActive = true 
     greySubview.heightAnchor.constraint(equalTo: greySubview.widthAnchor).isActive = true 
     let button = TornadoButton() 
     greySubview.addSubview(button) 
     button.translatesAutoresizingMaskIntoConstraints = false 
     button.widthAnchor.constraint(equalTo: greySubview.widthAnchor, multiplier: 0.09).isActive = true 
     button.heightAnchor.constraint(equalTo: greySubview.heightAnchor, multiplier: 0.2).isActive = true 
     //below constrains are needed, else the origin of the UIBezierPath is wrong 
     button.centerXAnchor.constraint(equalTo: greySubview.centerXAnchor).isActive = true 
     button.centerYAnchor.constraint(equalTo: greySubview.centerYAnchor, constant: self.view.frame.height * 0.35).isActive = true 
     self.view.layoutIfNeeded() 
     let orbit = CAKeyframeAnimation(keyPath: "position") 
     button.addTarget(self, action: #selector(tappedOnCard(_:)), for: .touchUpInside) 
     let circlePath = UIBezierPath(arcCenter: greySubview.frame.origin, radius: CGFloat(greySubview.frame.width * 0.5), startAngle: 0, endAngle: CGFloat.pi * 2, clockwise: true) 
     orbit.duration = 12 
     orbit.path = circlePath.cgPath 
     orbit.isAdditive = true 
     orbit.repeatCount = Float.greatestFiniteMagnitude 
     orbit.calculationMode = kCAAnimationPaced 
     orbit.rotationMode = kCAAnimationRotateAuto 
     button.layer.add(orbit, forKey: "orbit") 
     button.backgroundColor = .blue 
     let gr = UITapGestureRecognizer(target: self, action: #selector(onTap(gesture:))) 
     greySubview.addGestureRecognizer(gr) 
    } 

    @objc func onTap(gesture:UITapGestureRecognizer) { 
     let p = gesture.location(in: gesture.view) 
     let v = gesture.view?.hitTest(p, with: nil) 
    } 

    @IBAction func tappedOnCard(_ sender: UIButton){ 
     print(sender) 
    } 
} 

這幾乎工程，但：

我可以檢索按鈕，如果按鈕是100％可見在屏幕上。例如，如果它是50％可見（並且屏幕50％關閉（請看下面的圖片）），我不檢索按鈕點擊（即不檢索打印）。

如何在運行動畫中檢索按鈕，並且它可以稍微離開屏幕？

Answer 1

原來的答案：

這是非常有可能的是，UITapGestureRecognizer在greySubview被消耗的觸感，不讓它通過直到按鈕。試試這個：

gr.cancelsTouchesInView = NO; 

在將UITapGestureRecognizer添加到greySubview之前。

---

編輯答案：

請忽略我剛纔的答覆，並恢復了變化，如果你做到了。我的原始答案沒有意義，因爲在你的情況下，按鈕是grayView和cancelsTouchesInView的子視圖在視圖層次結構中向上工作，而不是向下。

經過大量的挖掘，我能夠弄清楚爲什麼會發生這種情況。這是因爲在動畫過程中TornadoButton中的命中測試不正確。由於您正在爲該按鈕設置動畫，因此您需要覆蓋TornadoButton的hitTest和pointInside方法，以便它們在命中測試時佔據動畫位置，而不是按鈕的實際位置。

pointInside方法的默認實現沒有考慮按鈕的動畫表示層，只是嘗試檢查矩形內的觸摸點（由於觸摸位於其他位置而失敗）。

的方法，下面的實現似乎做的伎倆：

class TornadoButton: UIButton{ 
    override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? { 
     let pres = self.layer.presentation()! 
     let suppt = self.convert(point, to: self.superview!) 
     let prespt = self.superview!.layer.convert(suppt, to: pres) 
     if (pres.hitTest(suppt)) != nil{ 
      return self 
     } 
     return super.hitTest(prespt, with: event) 
    } 

    override func point(inside point: CGPoint, with event: UIEvent?) -> Bool { 
     let pres = self.layer.presentation()! 
     let suppt = self.convert(point, to: self.superview!) 
     return (pres.hitTest(suppt)) != nil 
    } 
} 

Answer 2

我不完全得到，爲什麼你使用的按鈕用於顯示簡單的矩形時的觀點會工作爲好，但反正...在您添加的目標你沒告訴我們你的按鈕。

button.addTarget(self, action: #selector(ViewController.buttonPressed(_:)), for: .touchUpInside) // This is needed that your button 'does something' 
button.tag = 1 // This is a tag that you can use to identify which button has been pressed 

與功能buttonPressed看起來像這樣：

@objc func buttonPressed(_ button: UIButton) { 
    switch button.tag { 
    case 1: print("First button was pressed") 
    case 2: print("Second button was pressed") 
    default: print("I don't know the button you pressed") 
    } 
}