UIViewPropertyAnimator根據平移方向的動畫運動

Question

嗨，大家好我試圖讓我的動畫去任何一方取決於用戶平移的方式，但它不工作，我不知道什麼是錯的。當我只用一個方向工作時，該手勢正常工作，但是當我將邏輯移至moveLabel（）函數時，它不再起作用。動畫甚至沒有開始。我的目標是擁有相同的動畫（因爲我會爲其添加更多細節），但根據平移方向將此特定標籤向左或向右移動。這是我現在的感冒

import UIKit 

class ViewController: UIViewController { 

    @IBOutlet weak var labelDummy: UILabel! 

    var labelAnimation = UIViewPropertyAnimator() 

    override func viewDidLoad() { 
     super.viewDidLoad() 

     labelDummy.center.x = view.bounds.maxX/2 

     view.addGestureRecognizer(UIPanGestureRecognizer(target: self, action: #selector(self.moveLabel))) 

    } 


    func moveLabel(gesture: UIPanGestureRecognizer){ 

     let trans = gesture.translation(in: view) 

     if trans.x >= 0{ 
      labelAnimation = UIViewPropertyAnimator(duration: 1.0, curve: .easeInOut) { 

       let yPos = self.labelDummy.center.y 
       self.labelDummy.center = CGPoint(x: 100 + (self.labelDummy.frame.size.width/2), y: yPos) 
      } 
     } 

     if trans.x < 0 { 
      labelAnimation = UIViewPropertyAnimator(duration: 1.0, curve: .easeInOut) { 

       let yPos = self.labelDummy.center.y 
       self.labelDummy.center = CGPoint(x: 10 + (self.labelDummy.frame.size.width/2), y: yPos) 
      } 
     } 

     labelAnimation.fractionComplete = abs((trans.x/100)) 


     if gesture.state == .ended{ 

      labelAnimation.fractionComplete = 0 
     } 

     print("fractionCompleted: ", labelAnimation.fractionComplete) 
    } 
} 

我該如何解決這個問題？

這是工作的代碼：

import UIKit 

class ViewController: UIViewController { 

@IBOutlet weak var labelDummy: UILabel! 

var labelAnimation = UIViewPropertyAnimator() 

override func viewDidLoad() { 
    super.viewDidLoad() 


    labelDummy.center.x = view.bounds.maxX/2 

    // Pan for hele viewen som spiller label animasjon 

    view.addGestureRecognizer(UIPanGestureRecognizer(target: self, action: #selector(self.moveLabel))) 

    // animasjon 

    labelAnimation = UIViewPropertyAnimator(duration: 1.0, curve: .easeInOut) { 

     let yPos = self.labelDummy.center.y 
     self.labelDummy.center = CGPoint(x: 10 + (self.labelDummy.frame.size.width/2), y: yPos) 
    } 

    //labelAnimation.startAnimation() 
} 

func moveLabel(gesture: UIPanGestureRecognizer){ 

    print("retning: ", gesture.velocity(in: view).x) 
    let trans = gesture.translation(in: view) 
    print("trans: ", trans) 

    labelAnimation.fractionComplete = trans.x/100 
    print("fractionCompletet prøver å settes til : ", trans.x/100) 
    print(trans.x) 

    if gesture.state == .ended{ 
     print("-ENDED-") 
     labelAnimation.fractionComplete = 0 
    } 

    print("fractionCompletet: ", labelAnimation.fractionComplete) 
} 

}

Answer 1

最終作出對x位置的全局變量，並在moveLabel功能我用if語句類似 「如果.began」然後檢查翻譯。根據翻譯是高於還是低於0，將xposition設置在左側，或者在右側。

if gesture.state == .began { 

     if gesture.velocity(in: view).x > 0{ 

      // Panning right, Animate Left 
      self.animationDirection = .left 
      self.animateToXPos = CGPoint(x: headerLabelPositionLeft!, y: headerLabelPositionY!) 
      self.setAnimation(direction: AnimationDirection.left) 
      self.dayLabel.textAlignment = .left 

     } else { 

      // Panning left, Animate Right 
      self.animationDirection = AnimationDirection.right 
      self.animateToXPos = CGPoint(x: self.view.bounds.width - (self.dayLabel.frame.size.width/2), y: headerLabelPositionY) 
      self.setAnimation(direction: AnimationDirection.right) 
      self.dayLabel.textAlignment = .right 
     } 
    }