Swift coding convention

Swift_coding_convention_protocol.swift

 //Not preferred:
class MyViewController: UIViewController, UITableViewDataSource, UIScrollViewDelegate {
  // all methods
}
//Preferred:
class MyViewController: UIViewController {
  // class stuff here
}

// MARK: - UITableViewDataSource
extension MyViewController: UITableViewDataSource {
  // table view data source methods
}

// MARK: - UIScrollViewDelegate
extension MyViewController: UIScrollViewDelegate {
  // scroll view delegate methods
}