title: How to change UIButton border color when button is highlighted (or tapped on) in Swift 3?
body: <p>This is what I have as of now. Would Like to know how to change the border color of the button when it has been tapped or highlighted. So far, I have only been able to do this with the button's text color. Any help or tips would be great, thanks.</p>
  
  <pre><code>@IBOutlet weak var createNewWorkoutButton: UIButton!
  
  @IBAction func createWorkoutBtn(_ sender: UIButton) {
  
  }
  
  override func viewDidLoad() {
      super.viewDidLoad()
  
      createNewWorkoutButton.setTitleColor(UIColor .gray, for: UIControlState.highlighted)
  
      if createNewWorkoutButton = UIControlState.highlighted {
          createNewWorkoutButton.layer.borderColor = UIColor.gray.cgColor
      }
  
  }
  </code></pre>