我的scrollViewDidScroll函数没有接收调用

Question

我正在尝试检查用户是否在我的应用上上下滚动,但它没有调用我的scrollViewDidScroll方法

received scroll当我在应用程序上向上和向下滚动时,为什么它不打印的任何想法？

import UIKit

class CreateAccount: UIViewController, UITextFieldDelegate, UIScrollViewDelegate {

    @IBOutlet weak var scrollViewer: UIScrollView!
    @IBOutlet weak var usernameTextField: UITextField!
    @IBOutlet weak var emailTextField: UITextField!
    @IBOutlet weak var passwordTextField: UITextField!
    @IBOutlet weak var reenterPasswordTextField: UITextField!

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    func scrollViewDidScroll(scrollView: UIScrollView) {
        print("received scroll")
    }

}

Answer 1

添加scrollview委托.每当你实现一个委托方法时,你需要告诉它使用什么控制器,通常它会self.它让我抓了几次.

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view.   
    scrollViewer.delegate = self
}