问使用创建自定义UIView时出现问题，在@IBOutlet中发现nil时出现Xib错误

EN

class SuccessfulView: UIView{

  @IBOutlet weak var contentLabel: UILabel!

  convenience init(content:String ,frame: CGRect){
    self.init(frame:frame)
    contentLabel.text = content

  }

  required init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)



  }
  override init(frame: CGRect) {
    super.init(frame: frame) // calls designated initializer

  }



  func commonInit(){
    Bundle.main.loadNibNamed("SuccessfulFooterContentView", owner: self, options: nil)
    addSubview(contentLabel)
  }

}