FBLive-2.swift

 override func viewDidLoad() {
        super.viewDidLoad()
       
        let viewBox = UIView()
        viewBox.frame = CGRect(x: 0, y: 0, width: 50, height: 50)
        viewBox.backgroundColor = #colorLiteral(red: 0.7450980544, green: 0.1568627506, blue: 0.07450980693, alpha: 1)
        self.view.addSubview(viewBox)
        let path = createPath()
        self.debugPath(path: path)
        moveAlongPath(view: viewBox, path: path)
    }
    
    
    private func moveAlongPath(view:UIView , path:CGPath) {
        let pathAnimation = CAKeyframeAnimation(keyPath: "position")  
        pathAnimation.path = path 
        pathAnimation.calculationMode = .paced
        pathAnimation.fillMode = CAMediaTimingFillMode.forwards
        pathAnimation.duration = 5.0
        pathAnimation.isRemovedOnCompletion = false 
        view.layer.add(pathAnimation, forKey: nil)
    }
   
    private func createPath()->CGPath {
        let bezierPath:UIBezierPath = UIBezierPath()
        let midXPt:CGFloat = view.frame.size.width/2
        let midYPt:CGFloat = view.frame.size.height/2
        bezierPath.move(to: CGPoint(x: midXPt,  y: midYPt*2)) 
        bezierPath.addQuadCurve(to: CGPoint(x: midXPt , y: 0), controlPoint: CGPoint(x: midXPt + 100, y: midYPt))
        return bezierPath.cgPath
    }
    
    private func debugPath(path:CGPath) {
        let shapeLayer = CAShapeLayer()
        shapeLayer.path = path
        shapeLayer.fillColor = nil
        shapeLayer.strokeColor = UIColor.green.cgColor
        shapeLayer.lineWidth = 1
        self.view.layer.addSublayer(shapeLayer)
    }