List Load Showing Shimmer View

ShimmerView.swift

import UIKit

class ShimmerView: UIView {

    var primaryColor: UIColor = UIColor(red: 214.0/255.0, green: 214.0/255.0, blue: 214.0/255.0, alpha: 1.0)
    var animationColor: UIColor = .white
    
    
    override init(frame: CGRect) {
        super.init(frame: frame)
        initialSetUp()
    }
    
    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        initialSetUp()
    }
    
    func initialSetUp() {
        //backgroundColor = primaryColor
        //layer.masksToBounds = true
        //layer.cornerRadius = bounds.height / 2.0
    }

}

class RoundRectView: UIView {
    

    override init(frame: CGRect) {
        super.init(frame: frame)
        initialSetUp()
    }
    
    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        initialSetUp()
    }
    
    func initialSetUp() {
        layer.masksToBounds = true
        layer.cornerRadius = bounds.height / 2.0
    }
    
}

class Animate {
    
    /// Add a persistent shimmer animation. Usage: `Animate.shimmer(myView)`
    static func startShimming(view: UIView, afterDelay delay: Double) {
        let gradient = CAGradientLayer()
        gradient.startPoint = CGPoint(x:0, y:0)
        gradient.endPoint = CGPoint(x:1, y:0.0)
        gradient.frame = CGRect(x:0, y:0, width:view.bounds.size.width*3, height:view.bounds.size.height)
        
        let lowerAlpha: CGFloat = 0.7
        let solid = UIColor(white: 1, alpha: 1).cgColor
        let clear = UIColor(white: 1, alpha: lowerAlpha).cgColor
        gradient.colors     = [ solid, solid, clear, clear, solid, solid ]
        gradient.locations  = [ 0,     0.3,   0.45,  0.55,  0.7,   1     ]
        
        let theAnimation : CABasicAnimation = CABasicAnimation(keyPath: "transform.translation.x")
        theAnimation.beginTime = CACurrentMediaTime() + delay
        theAnimation.duration = 0.8
        theAnimation.repeatCount = Float.infinity
        theAnimation.autoreverses = false
        theAnimation.isRemovedOnCompletion = false
        theAnimation.fillMode = kCAFillModeForwards
        theAnimation.fromValue = -view.frame.size.width * 2
        theAnimation.toValue =  0
        gradient.add(theAnimation, forKey: "animateLayer")
        
        view.layer.mask = gradient
        
    }
}