从一个班级到另一个班级的代表为零

Question

我有这个协议和类，它是委托者

protocol userDetailsDelegate: AnyObject {
    func didSendUserDetails ( _ object: LoginViewController)
}


class LoginViewController: UIViewController {

    var details: loginDetails?

    var userdelegate: userDetailsDelegate?


    func loginRequestrd() {

        // ALOT OF CODE ABOVE BUT THE DATA BELOW SURE COMES

        guard let logdetails = try? JSONDecoder().decode(loginDetails.self, from: data) else {
//                        print("====")
            return
        }

        self.details = loginDetails(status: logdetails.status, message: logdetails.message, id: logdetails.id, username: logdetails.username, email: logdetails.email, fullname: logdetails.fullname, ava: logdetails.ava)
        // THE DETAILS COME AS RESPONSE NO ISSUE
        self.didSendUserData()

        DispatchQueue.main.async {
            self.navigationController?.pushViewController(HomePageViewController(), animated: true )
        }
    }

    func didSendUserData () {
        guard let userdetails = details else {
            return
        }
        userdelegate?.didSendUserDetails(self)
    }

   }
}

我也有这个类，它是代表：

class HomePageViewController: UITabBarController {
    
    var userdetails: loginDetails?
    var posttitle: String?
    var loginview: LoginViewController?
    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = .systemBackground
           UITabBar.appearance().barTintColor = .systemBackground
           tabBar.tintColor = .label
        DispatchQueue.main.async {
            self.setupVCs()
        }
        loginview?.userdelegate = self
        loginview?.loginRequestrd()
       
    }
}

/ 符合 userDetailsDelegate 协议

extension HomePageViewController: userDetailsDelegate   {
    func didSendUserDetails(_ object: LoginViewController) {
        self.userdetails = object.details
    }
}

委托类中的用户详细信息为 nil 。不确定我在协议一致性方面缺少什么

Answer 1

当你在这里调用这个方法(

didSendUserData

)时

    // THE DETAILS COME AS RESPONSE NO ISSUE
    self.didSendUserData()

===
func didSendUserData () {
    guard let userdetails = details else {
        return
    }
    userdelegate?.didSendUserDetails(self)
}

userdelegate

是

nil

，您可以通过

解决此问题

    self.details = loginDetails(status: logdetails.status, message: logdetails.message, id: logdetails.id, username: logdetails.username, email: logdetails.email, fullname: logdetails.fullname, ava: logdetails.ava)
    // THE DETAILS COME AS RESPONSE NO ISSUE
     let vc = HomePageViewController()
    self.userdelegate = vc
    self.didSendUserData() 
    DispatchQueue.main.async {
        self.navigationController?.pushViewController(vc, animated: true )
    }

但是你需要从登录屏幕发送数据到home，这里不需要委托，你只需要通过属性转发数据

    // THE DETAILS COME AS RESPONSE NO ISSUE
    //self.didSendUserData() // remove this line

    DispatchQueue.main.async {
      let vc=  HomePageViewController(
      vc. userdetails = self. details
      self.navigationController?.pushViewController(), animated: true )
    }