title: Custom UIButton setSelected weird behavior
body: <p>I'm new to swift and I'm just trying to create a subclass of uibutton. Except that I have this weird blue rounded rect appearing when the button is selected as shown below. When all I want is a nice white border.</p>
  
  <p><img src="https://i.stack.imgur.com/4Dffo.png" alt="enter image description here"></p>
  
  <p>The code of my class :</p>
  
  <pre><code>import UIKit
  import QuartzCore
  
  @IBDesignable
  class ColorButton: UIButton {
      //MARK: PROPERTIES
      @IBInspectable var stickerColor: UIColor = UIColor.whiteColor() {
          didSet {
              configure()
          }
      }
  
      override var selected: Bool {
          willSet(newValue) {
              super.selected = newValue;
              if selected {
                  layer.borderWidth = 1.0
              } else {
                  layer.borderWidth = 0.0
              }
          }
      }
  
      //MARK: Initializers
      override init(frame : CGRect) {
          super.init(frame : frame)
          setup()
          configure()
      }
  
      convenience init() {
          self.init(frame:CGRectZero)
          setup()
          configure()
      }
  
      required init(coder aDecoder: NSCoder) {
          super.init(coder: aDecoder)
          setup()
          configure()
      }
  
  
      override func awakeFromNib() {
          super.awakeFromNib()
          setup()
          configure()
      }
  
      override func prepareForInterfaceBuilder() {
          super.prepareForInterfaceBuilder()
          setup()
          configure()
      }
  
      func setup() {
          //Border color
          layer.borderColor = UIColor.whiteColor().CGColor
          //Corner Radius
          setUpCornerRadius()
      }
  
      func configure() {
          backgroundColor = stickerColor
      }
  
      override func layoutSubviews() {
          super.layoutSubviews()
          setUpCornerRadius()
      }
  
      func setUpCornerRadius() {
          layer.cornerRadius = CGRectGetWidth(bounds) * 0.205
      }
  }
  </code></pre>