很簡(jiǎn)單的一個(gè)點(diǎn)擊事件，不知道錯(cuò)誤在哪里。剛開始學(xué)ios
viewcontroller代嗎

class HomeViewController: BaseViewController {
    
    
   
    override func viewDidLoad() {
        super.viewDidLoad()
        
        let btn = UIButton.init().custom(title: "返回", action: #selector(add))
        navigationItem.leftBarButtonItem  = UIBarButtonItem.init(customView: btn)
    }
    @objc  func add()  {
        print("xe")
    }
    
    override func initUi() {
        super.initUi()
    }
}

擴(kuò)展的uibutton

extension UIButton {
    
    
    
    func custom(title:String,fontSize:CGFloat,normalColor:UIColor,action:Selector)->UIButton{
        return base(title:title,fontSize:fontSize,normalColor:normalColor,action:action)
    }
    
    func custom(title:String,action:Selector)->UIButton{
        return base(title:title,fontSize:16,normalColor:UIColor.black,action:action)
    }
    
    func base(title:String,fontSize:CGFloat,normalColor:UIColor,action:Selector)->UIButton{
        let btn = UIButton.init()
        btn.setTitle(title, for: .normal)
        
        btn.titleLabel?.font=UIFont.systemFont(ofSize: fontSize)
        btn.setTitleColor(normalColor, for: .normal)
        btn.addTarget(self, action:action, for: .touchUpInside)
        return btn;
    }
}

請(qǐng)大神指教下，感激