ios - 如何将数据从 TabBarController View 之一传递到非 TabBarController View ？

Question

我正在开发一个项目，当我们选择某些内容时，Initial View 有一个 PickerView。我将此数据作为 String 传递给 TabBarController，然后从 TabBarController 传递给他的每 5 个“ child ”。

到目前为止，一切正常。

现在，通过单击 TableViewCell，我想将数据从 TabBarController 的 子级 (ViewController) 传递到非 TabBarController View ( FullNewsViewController) 并显示此 View 。我尝试了几种方法，但没有任何效果。你能帮我吗？

我正在使用 Swift 5 和 Xcode 10.2。

这是我的 View Controller ，我想从中下载“FinalTeam”:

import UIKit
import FirebaseDatabase

class ViewController: UIViewController, UITableViewDelegate, 
     UITableViewDataSource {

@IBOutlet weak var imageView: UIImageView!
var ref: DatabaseReference?
var refHandle: DatabaseHandle?
var news = [String]()
var FinalTeam = ""

@IBOutlet weak var tableView: UITableView!
@IBOutlet weak var infoLabel: UILabel!

override func viewDidLoad() {
    super.viewDidLoad()
    let tabbar = tabBarController as! TabBarViewController
    var FinalTeam = tabbar.Team
   // infoLabel.text = String(describing: tabbar.Team)
    infoLabel.text = FinalTeam
    tableView.delegate = self
    tableView.dataSource = self
    ref = Database.database().reference()
    switch FinalTeam {
    case "Lech Poznań":
        imageView.image = UIImage(named: "leszek")
        refHandle = ref?.child("News/Lech/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)
                self.tableView.reloadData()
            }
        })
    case "Legia Warszawa":
        imageView.image = UIImage(named: "legia")
        refHandle = ref?.child("News/Legia/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Lechia Gdańsk":
        imageView.image = UIImage(named: "lechia")
        refHandle = ref?.child("News/Lechia/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Wisła Płock":
        imageView.image = UIImage(named: "wisla_p")
        refHandle = ref?.child("News/Wisła_P/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Wisła Kraków":
        imageView.image = UIImage(named: "wisla_k")
        refHandle = ref?.child("News/Wisła_K/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Jagiellonia Białystok":
        imageView.image = UIImage(named: "jaga")
        refHandle = ref?.child("News/Jaga/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Piast Gliwice":
        imageView.image = UIImage(named: "piast")
        refHandle = ref?.child("News/Piast/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Pogoń Szczecin":
        imageView.image = UIImage(named: "pogon")
        refHandle = ref?.child("News/Pogoń/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Korona Kielce":
        imageView.image = UIImage(named: "korona")
        refHandle = ref?.child("News/Korona/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Cracovia":
        imageView.image = UIImage(named: "cracovia")
        refHandle = ref?.child("News/Cracovia/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Śląsk Wrocław":
        imageView.image = UIImage(named: "slask")
        refHandle = ref?.child("News/Śląsk/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Miedź Legnica":
        imageView.image = UIImage(named: "miedz")
        refHandle = ref?.child("News/Miedź/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Zagłębie Sosnowiec":
        imageView.image = UIImage(named: "zaglebie_s")
        refHandle = ref?.child("News/Zagłębie_S/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Zagłębie Lubin":
        imageView.image = UIImage(named: "zaglebie_l")
        refHandle = ref?.child("News/Zagłębie_L/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Górnik Zabrze":
        imageView.image = UIImage(named: "gornik")
        refHandle = ref?.child("News/Górnik/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    case "Arka Gdynia":
        imageView.image = UIImage(named: "arka")
        refHandle = ref?.child("News/Arka/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })

    default:
        imageView.image = UIImage(named: "lech")
        refHandle = ref?.child("News/Lech/Naglowek").observe(.value, with: { (snapshot) in
            let post = snapshot.value as? String
            if let actualPost = post {
                self.news.append(actualPost)

                self.tableView.reloadData()
            }
        })
    }
}

func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return news.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: "newsCell")
    cell?.textLabel?.text = news[indexPath.row]
    return cell!
}

}

这是我的 FullNewsViewController，我想向其中发送此数据:

import UIKit
import FirebaseDatabase

class FullNewsViewController: UIViewController,UITextViewDelegate {


@IBOutlet weak var titleLabel: UILabel!
@IBOutlet weak var contentTextView: UITextView!
@IBAction func button(_ sender: Any) {
    navigationController?.popViewController(animated: true)
    dismiss(animated: true, completion: nil)
}

var ref: DatabaseReference?
var refHandleTitle: DatabaseHandle?
var refHandleContent: DatabaseHandle?
var news = [String]()
var FinalTeam = ""

override func viewDidLoad() {
    super.viewDidLoad()
    ref = Database.database().reference()
    contentTextView.delegate = self

    switch FinalTeam {
    case "Lech Poznań":
        //imageView.image = UIImage(named: "leszek")
        refHandleTitle = ref?.child("News/Lech/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Lech/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Legia Warszawa":
        //imageView.image = UIImage(named: "legia")
        refHandleTitle = ref?.child("News/Legia/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Legia/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Lechia Gdańsk":
        //imageView.image = UIImage(named: "lechia")
        refHandleTitle = ref?.child("News/Lechia/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Lechia/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Wisła Płock":
        //imageView.image = UIImage(named: "wisla_p")
        refHandleTitle = ref?.child("News/Wisła_P/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Wisła_P/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Wisła Kraków":
        //imageView.image = UIImage(named: "wisla_k")
        refHandleTitle = ref?.child("News/Wisła_K/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Wisła_K/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Jagiellonia Białystok":
        //imageView.image = UIImage(named: "jaga")
        refHandleTitle = ref?.child("News/Jaga/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Jaga/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Piast Gliwice":
       // imageView.image = UIImage(named: "piast")
        refHandleTitle = ref?.child("News/Piast/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Piast/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Pogoń Szczecin":
       // imageView.image = UIImage(named: "pogon")
        refHandleTitle = ref?.child("News/Pogoń/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Pogoń/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Korona Kielce":
       // imageView.image = UIImage(named: "korona")
        refHandleTitle = ref?.child("News/Korona/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Korona/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Cracovia":
        //imageView.image = UIImage(named: "cracovia")
        refHandleTitle = ref?.child("News/Cracovia/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Cracovia/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Śląsk Wrocław":
       // imageView.image = UIImage(named: "slask")
        refHandleTitle = ref?.child("News/Śląsk/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Śląsk/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Miedź Legnica":
       // imageView.image = UIImage(named: "miedz")
        refHandleTitle = ref?.child("News/Miedź/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Miedź/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Zagłębie Sosnowiec":
       // imageView.image = UIImage(named: "zaglebie_s")
        refHandleTitle = ref?.child("News/Zagłębie_S/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Zagłębie_S/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Zagłębie Lubin":
       // imageView.image = UIImage(named: "zaglebie_l")
        refHandleTitle = ref?.child("News/Zagłębie_L/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Zagłębie_L/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Górnik Zabrze":
       // imageView.image = UIImage(named: "gornik")
        refHandleTitle = ref?.child("News/Górnik/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Górnik/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    case "Arka Gdynia":
      //  imageView.image = UIImage(named: "arka")
        refHandleTitle = ref?.child("News/Arka/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Arka/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })

    default:
      //  imageView.image = UIImage(named: "lech")
        refHandleTitle = ref?.child("News/Lech/Naglowek").observe(.value, with: { (snapshot) in
            let titlePost = snapshot.value as? String
            if let actualTitlePost = titlePost {
                self.news.append(actualTitlePost)
            }
            self.titleLabel.text = titlePost
        })
        refHandleContent = ref?.child("News/Lech/Tresc").observe(.value, with: { (snapshot) in
            let contentPost = snapshot.value as? String
            if let actualContentPost = contentPost {
                self.news.append(actualContentPost)
            }
            self.contentTextView.text = contentPost
        })
    }
}

}

This is my Storyboard

Answer 1

我们需要知道您的“子” View Controller 和“非 TabBarController”之间的关系，以给出哪种方式是合适的。

一般来说有几个程序，具体取决于具体情况。首先是转发数据。当您创建一个新屏幕并想要传递前一个屏幕的数据时，通常会使用它:

private func showUsersViewController(_ users: [User]) {
    let controller = UIStoryboard(name: "User", bundle: nil).instantiateViewController(withIdentifier: "UserListViewController") as! UserListViewController
    controller.users = users
    present(controller, animated: true, completion: nil)
    // navigationController?.pushViewController(controller, animated: true)
}

但是，如果您想取回信息，例如在上述情况下，当用户被按下时，您将在此屏幕上执行某些操作，则可以使用委托(delegate)。

private func showUsersViewController(_ users: [User]) {
    let controller = UIStoryboard(name: "User", bundle: nil).instantiateViewController(withIdentifier: "UserListViewController") as! UserListViewController
    controller.users = users
    controller.delegate = self
    present(controller, animated: true, completion: nil)
    // navigationController?.pushViewController(controller, animated: true)
}

在用户列表 Controller 中

protocol UserListViewControllerDelegate: class {
    func userListViewController(_ sender: UserListViewController, didSelectUser user: User)
}

class UserListViewController: UIViewController, UITableViewDelegate {

    weak var delegate: UserListViewControllerDelegate?

    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        delegate?.userListViewController(self, didSelectUser: users[indexPath.row])
    }

}

然后回到主视图 Controller

extension ViewController: UserListViewControllerDelegate {

    func userListViewController(_ sender: UserListViewController, didSelectUser user: User) {
        self.user = user
        self.reloadUI()
    }

}

因此，在这种情况下，您同时有 2 个 View Controller ，它们可以在两个方向上相互通信。

这两个过程通常足以解决两个 View Controller 之间的几乎所有通信。但还有其他方法，例如使用选择器、使用通知、MVVM...