akshitzaveri

import UIKit

class ViewController: UIViewController {

  @IBOutlet weak var tableView: UITableView!

  override func viewDidLoad() {
    super.viewDidLoad()
    self.tableView.register(UITableViewCell.self, forCellReuseIdentifier: "cell")
  }

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self.miniCircleView.center = self.getPoint(for: -90)

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// 2
let initialPoint = self.getPoint(for: -90)
path.move(to: initialPoint)

// 3
for angle in -89...0 { path.addLine(to: self.getPoint(for: angle)) }
for angle in 1...270 { path.addLine(to: self.getPoint(for: angle)) }

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let newCenterX = radius + radius * cos(radian)
let newCenterY = radius + radius * sin(radian)

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@IBAction func buttonTapped(_ sender: UIButton) {
  self.circleView.startAnimating()
}

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private func animate(view: UIView, path: UIBezierPath) {
  // 1
  let animation = CAKeyframeAnimation(keyPath: "position")

  // 2
  animation.path = path.cgPath

  // 3
  animation.repeatCount = 1

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private func getPoint(for angle: Int) -> CGPoint {
  // 1
  let radius = Double(self.circleView.layer.cornerRadius)

  // 2
  let radian = Double(angle) * Double.pi / Double(180)

  // 3
  let newCenterX = radius * cos(radian)
  let newCenterY = radius * sin(radian)

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// MARK: - Animation

func startAnimating() {
  // 1
  let path = UIBezierPath()

  // 2
  let initialPoint = self.getPoint(for: 0)
  path.move(to: initialPoint)

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self.clipsToBounds = false

self.addSubview(self.circleView)
NSLayoutConstraint.activate([
  self.circleView.leadingAnchor.constraint(equalTo: self.leadingAnchor),
  self.circleView.topAnchor.constraint(equalTo: self.topAnchor),
  self.circleView.trailingAnchor.constraint(equalTo: self.trailingAnchor),
  self.circleView.bottomAnchor.constraint(equalTo: self.bottomAnchor)
])

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override func layoutSubviews() {
  super.layoutSubviews()
  self.circleView.layer.cornerRadius = self.circleView.frame.width / 2.0
  self.miniCircleView.layer.cornerRadius = self.miniCircleView.frame.width / 2.0
}