title: IBInspectable button inside IBDesignable view
body: <p>I have an IBInspectable button inside IBDesignable view.
  I tried several things but my icon is not displayed when I run my program.
  The worst is : I can see it on storyboard inside my view but when I run icon is not set.</p>
  
  <p>What am I doing wrong, I don't understand</p>
  
  <pre><code>@IBDesignable class CustomView: UIView {
     @IBOutlet weak var firstIcon: UIButton!
  
      //Not working
      override func prepareForInterfaceBuilder() {
        let designTimeBundle = Bundle(for: CustomView.self)
  
        let image = UIImage(named: "home", in: designTimeBundle, 
        compatibleWith: nil)
  
        firstIcon.setImage(image, for: .normal)
     }
     //Not working either
     @IBInspectable var firstButtonIcon: UIButton {
      let bundle = Bundle(for: CustomView.self)
      let image = UIImage(named: "home", in: bundle, 
      compatibleWith: nil)
      firstIcon.setImage(image, for: .normal)
  
      return firstIcon
     }
  
     //And still not
     @IBInspectable var firstButtonIcon: UIButton! {
      firstIcon.setImage(UIImage(named: "home"), for: .normal)
  
      return firstIcon
     } 
  }
  </code></pre>