import UIKit

class ViewController: UIViewController {

  @IBOutlet weak var sizeSlider: UISlider!

  var label: UILabel!
  var textField: UITextField!

  var labelBaseSize: CGSize!
  var textFielBasedSize: CGSize!

  var isLabelSelected = true
  var selectedView: UIView!

  override func viewDidLoad() {
    super.viewDidLoad()

    label = UILabel(frame: CGRect(x: 0, y: 0, width: 36, height: 26))
    label.text = "This is a UILabel"
    label.backgroundColor = UIColor.gray
    label.textAlignment = .center
    label.sizeToFit()
    view.addSubview(label)
    labelBaseSize = label.bounds.size
    label.center = view.convert(view.center, from:view.superview)

    textField = UITextField(frame: CGRect(x: 0, y: 0, width: 36, height: 26))
    textField.text = "This is a UITextField"
    textField.backgroundColor = UIColor.gray
    textField.textAlignment = .center
    textField.sizeToFit()
    view.addSubview(textField)
    textFielBasedSize = textField.bounds.size
    textField.center = view.convert(view.center, from:view.superview)

    textField.isHidden = true
    selectedView = label

    sizeSlider.minimumValue = 0
    sizeSlider.maximumValue = 10
  }

  @IBAction func labelAction(_ sender: UIButton) {
    label.isHidden = false
    textField.isHidden = true
    selectedView = label
  }

  @IBAction func textFieldAction(_ sender: UIButton) {
    label.isHidden = true
    textField.isHidden = false
    selectedView = textField
  }

  @IBAction func sizeChange(_ sender: UISlider) {
    let scaleFactor = CGFloat(sender.value)
    // CGAffineTransform will rastarize the text and make it blurry
//    selectedView.transform = CGAffineTransform(scaleX: scaleFactor, y: scaleFactor)

    let baseSize = isLabelSelected ? labelBaseSize : textFielBasedSize
    selectedView.bounds = CGRect(x: selectedView.bounds.origin.x,
                                 y: selectedView.bounds.origin.y,
                                 width: baseSize!.width * scaleFactor,
                                 height: baseSize!.height * scaleFactor)
  }
}