Swift: Kaydırma sonrası yumuşak atalet nasıl yapılır (sürükleme)?

Question

Birkaç gün boyunca Swift 2.2'yi öğreniyorum. Resmi eğitimi bitirdikten sonra, bazı fonksiyonel örnekler yapmaya çalışıyorum. Örneğin. Bir avatar dekoratörünü yapmaya çalışıyorum. Eğer ben tava jest tanıyıcı ".Ended" durumunda ataleti sürükleyerek taşıma ediyorum gördüğünüz gibi Tamam

@IBAction func moveAvatar(recognizer:UIPanGestureRecognizer) { 
    recognizer.maximumNumberOfTouches = 1 
    recognizer.minimumNumberOfTouches = 1 
    let debugOutOfBounds = false 
    let debugGestureRecognizer = false 
    let debugVelocity = true 
    if (debugGestureRecognizer) { 
     print("pan") 
    } 
    let translation = recognizer.translationInView(self.avatar) 

    let standardAvatarSize:CGFloat = Conf.Size.avatarRadius * 2 
    if (self.avatar.frame.width < standardAvatarSize) { 
     self.avatar.frame = CGRect(origin: self.avatar.frame.origin, size: CGSize(width: standardAvatarSize, height:standardAvatarSize)) 
    } 
    if let view = recognizer.view { 
     switch recognizer.state { 
     case .Began: 
      if (debugVelocity) { 
       print("Began: velocity: \(recognizer.velocityInView(view)) translation: \(translation)") 
      } 

      self.panAvatarLastTranslation = translation 
      self.avatar.center = CGPoint(x: self.avatar.center.x + translation.x, y: self.avatar.center.y + translation.y) 
     case .Changed: 
      if (debugVelocity) { 
       print("Changed: velocity: \(recognizer.velocityInView(view)) translation: \(translation)") 
      } 
      if (translation != CGPoint(x: 0.0, y: 0.0)) { 
       self.panAvatarLastTranslation = translation 
      } 
      self.avatar.center = CGPoint(x: self.avatar.center.x + translation.x, y: self.avatar.center.y + translation.y) 
     case .Ended: 
      if (debugVelocity) { 
       print("Ended: velocity: \(recognizer.velocityInView(view)) translation: \(translation)") 
      } 
      let velocityDistance = sqrt(pow(recognizer.velocityInView(view).x, CGFloat(2)) + pow(recognizer.velocityInView(view).y, CGFloat(2))) 
      print(velocityDistance) 
      if (velocityDistance > 100) { 
       let inertiaDelay: NSTimeInterval = 0.5 
       let inertiaDistance : CGFloat = velocityDistance * CGFloat(inertiaDelay) * 0.02 
       let inertiaX:CGFloat = self.panAvatarLastTranslation.x * inertiaDistance 
       let inertiaY:CGFloat = self.panAvatarLastTranslation.y * inertiaDistance 
            //sqrt(pow(inertiaX, CGFloat(2)) + pow(inertiaY, CGFloat(2))) 
       //print("inertiaDelay: \(inertiaDelay)") 
       UIView.animateWithDuration(inertiaDelay, animations: { 
        self.avatar.center.x += inertiaX 
        self.avatar.center.y += inertiaY 
       }) 
      } 
     default: 
      print("default") 
     } 

     let standardAvatarBound: [String:CGFloat] = [ 
      "top": UIApplication.sharedApplication().statusBarFrame.height + UIScreen.mainScreen().bounds.width/2 - Conf.Size.avatarRadius, 
      "right": UIScreen.mainScreen().bounds.width/2 + Conf.Size.avatarRadius, 
      "bottom": UIApplication.sharedApplication().statusBarFrame.height + UIScreen.mainScreen().bounds.width/2 + Conf.Size.avatarRadius, 
      "left": UIScreen.mainScreen().bounds.width/2 - Conf.Size.avatarRadius 
     ] 
     let avatarBound: [String:CGFloat] = [ 
      "top": self.avatar.center.y - self.avatar.frame.height/2, 
      "right": self.avatar.frame.width/2 + self.avatar.center.x, 
      "bottom": self.avatar.center.y + self.avatar.frame.height/2, 
      "left": self.avatar.center.x - self.avatar.frame.width/2 
     ] 

     if (self.panAvatarLastTranslation.x < 0 && avatarBound["right"] < standardAvatarBound["right"]) { 
      UIView.animateWithDuration(0.5, animations: { 
       self.avatar.center.x += (standardAvatarBound["right"]! - avatarBound["right"]!) 
      }) 
      if (debugOutOfBounds) { 
       print("Out of right bound") 
      } 
     } 

     if(self.panAvatarLastTranslation.x > 0 && avatarBound["left"] > standardAvatarBound["left"]) { 
      UIView.animateWithDuration(0.5, animations: { 
       self.avatar.center.x -= (avatarBound["left"]! - standardAvatarBound["left"]!) 
      }) 
      if (debugOutOfBounds) { 
       print("Out of left bound") 
      } 
     } 

     if(self.panAvatarLastTranslation.y > 0 && avatarBound["top"] > standardAvatarBound["top"]) { 
      UIView.animateWithDuration(0.5, animations: { 
       self.avatar.center.y -= (avatarBound["top"]! - standardAvatarBound["top"]!) 
      }) 
      if (debugOutOfBounds) { 
       print("Out of top bound") 
      } 
     } 
     if(self.panAvatarLastTranslation.y < 0 && avatarBound["bottom"] < standardAvatarBound["bottom"]) { 
      UIView.animateWithDuration(0.5, animations: { 
       self.avatar.center.y += (standardAvatarBound["bottom"]! - avatarBound["bottom"]!) 
      }) 
      if (debugOutOfBounds) { 
       print("Out of bottom bound") 
      } 
     } 
    } 
    recognizer.setTranslation(CGPointZero, inView: view) 
} 

. İyi çalışıyor, ancak düzgün değil. Düz bir kaydırma ataleti yapmak için ne yapabilirim? https://github.com/AarioAi/NotesOpen/tree/master/Swift

Answer 1

hareketlendirmek için farklı bir yöntem kullanmayı deneyin: İşte

kaynak kodudur. Hissedin this tutorial