override func viewDidLoad() {
super.viewDidLoad()
view?.backgroundColor = UIColor.white
view.addSubview(imageOnDisplay)
view.addSubview(activityIndicator)
view.addSubview(nextImageButton)
view.addSubview(transparencySlider)
activityIndicator.stopAnimating()
setImageOnDisplay()
setActivityIndicator()
setNextImageButton()
setTransparencySlider()
}