如何使TextView的滚动条在Swift中始终可见

let textView = UITextView(frame: CGRect(x: 0, y: 0, width: 200, height: 200))
textView.text = "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed euismod, urna id aliquet ultrices, nunc nunc tincidunt nunc, id lacinia nunc nunc id nunc."
textView.font = UIFont.systemFont(ofSize: 16)

textView.showsVerticalScrollIndicator = true
textView.showsHorizontalScrollIndicator = true

textView.indicatorStyle = .default

view.addSubview(textView)