XcodePlaygrounds中的UIViewController和UIView类我想弄清楚如何在XcodePlaygrounds中创建UIViewController并将UIView子类附加到它。我对swift和编码还很陌生，所以遇到了一些麻烦。classmyView:UIView{varlabel:UIButton!vartopHeader:UIImageView!varnameText:UITextField!varpassword:UITextField!overrideinit(frame:CGRect){super.init(frame:CGRect(x:10,y:10,