是否可以通过.appearance()上的setValue设置通用属性?
例如
@IBDesignable class Button: UIView {
@IBInspectable dynamic var color: UIColor? = .blue
}
let button = Button()
let app = type(of: button).appearance()
// works
print(app.color)
// crashes
app.setValue(UIColor.blue, forKey: "color")