Ios 为什么在和嵌入式tableView中显示领域数据并不容易？

无法在嵌入视图控制器的表视图中显示来自领域的数据。这里有一些代码

处理数据存储方案的数据模型类（这是一个财务跟踪应用程序）：

class Entry: Object {
    @objc dynamic var name: String = ""
    @objc dynamic var amount: Int = 0
    @objc dynamic var date: Date?
    var isExpense: Bool = false

    // initialization block dropped for concise post purposes
}

class FinanceOverviewCell: UITableViewCell {

    @IBOutlet weak var entryNameLabel: UILabel!
    @IBOutlet weak var entryAmountLabel: UILabel!

    func updateData(name: String, amount: String) {
        entryNameLabel?.text = name
        entryAmountLabel?.text = amount
    }
}

import UIKit
import RealmSwift

class FinanceOverviewController: UIViewController {

    @IBOutlet weak var financeOverviewTableView: UITableView!
    @IBOutlet weak var currentBalanceLabel: UILabel!

    var realm = try! Realm()
    let tableEntries = try! Realm().objects(Entry.self)
    let entriesManager = EntriesManager()
    var notificationToken: NotificationToken?

    override func viewDidLoad() {
        super.viewDidLoad()
        print(tableEntries)

        self.financeOverviewTableView.reloadData()
        financeOverviewTableView.delegate = self
        financeOverviewTableView.dataSource = self

        // notification token code block dropped for concise post purposes

        // outlets code block removed for concise post purposes

extension FinanceOverviewController: UITableViewDelegate {    
    func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCell.EditingStyle, forRowAt indexPath: IndexPath) {
        if editingStyle == .delete {
            realm.beginWrite()
            realm.delete(tableEntries[indexPath.row])
            try! realm.commitWrite()
        }
    }
}

extension FinanceOverviewController: UITableViewDataSource {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return tableEntries.count
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = financeOverviewTableView.dequeueReusableCell(withIdentifier: "FinanceOverviewCell", for: indexPath) as! FinanceOverviewCell
        let tableData = tableEntries[indexPath.row]

        cell.updateData(name: tableData.name, amount: String(tableData.amount))

        return cell
    }
}

单元类：

class Entry: Object {
    @objc dynamic var name: String = ""
    @objc dynamic var amount: Int = 0
    @objc dynamic var date: Date?
    var isExpense: Bool = false

    // initialization block dropped for concise post purposes
}

class FinanceOverviewCell: UITableViewCell {

    @IBOutlet weak var entryNameLabel: UILabel!
    @IBOutlet weak var entryAmountLabel: UILabel!

    func updateData(name: String, amount: String) {
        entryNameLabel?.text = name
        entryAmountLabel?.text = amount
    }
}

import UIKit
import RealmSwift

class FinanceOverviewController: UIViewController {

    @IBOutlet weak var financeOverviewTableView: UITableView!
    @IBOutlet weak var currentBalanceLabel: UILabel!

    var realm = try! Realm()
    let tableEntries = try! Realm().objects(Entry.self)
    let entriesManager = EntriesManager()
    var notificationToken: NotificationToken?

    override func viewDidLoad() {
        super.viewDidLoad()
        print(tableEntries)

        self.financeOverviewTableView.reloadData()
        financeOverviewTableView.delegate = self
        financeOverviewTableView.dataSource = self

        // notification token code block dropped for concise post purposes

        // outlets code block removed for concise post purposes

extension FinanceOverviewController: UITableViewDelegate {    
    func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCell.EditingStyle, forRowAt indexPath: IndexPath) {
        if editingStyle == .delete {
            realm.beginWrite()
            realm.delete(tableEntries[indexPath.row])
            try! realm.commitWrite()
        }
    }
}

extension FinanceOverviewController: UITableViewDataSource {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return tableEntries.count
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = financeOverviewTableView.dequeueReusableCell(withIdentifier: "FinanceOverviewCell", for: indexPath) as! FinanceOverviewCell
        let tableData = tableEntries[indexPath.row]

        cell.updateData(name: tableData.name, amount: String(tableData.amount))

        return cell
    }
}

最后，查看控制器：

class Entry: Object {
    @objc dynamic var name: String = ""
    @objc dynamic var amount: Int = 0
    @objc dynamic var date: Date?
    var isExpense: Bool = false

    // initialization block dropped for concise post purposes
}

class FinanceOverviewCell: UITableViewCell {

    @IBOutlet weak var entryNameLabel: UILabel!
    @IBOutlet weak var entryAmountLabel: UILabel!

    func updateData(name: String, amount: String) {
        entryNameLabel?.text = name
        entryAmountLabel?.text = amount
    }
}

import UIKit
import RealmSwift

class FinanceOverviewController: UIViewController {

    @IBOutlet weak var financeOverviewTableView: UITableView!
    @IBOutlet weak var currentBalanceLabel: UILabel!

    var realm = try! Realm()
    let tableEntries = try! Realm().objects(Entry.self)
    let entriesManager = EntriesManager()
    var notificationToken: NotificationToken?

    override func viewDidLoad() {
        super.viewDidLoad()
        print(tableEntries)

        self.financeOverviewTableView.reloadData()
        financeOverviewTableView.delegate = self
        financeOverviewTableView.dataSource = self

        // notification token code block dropped for concise post purposes

        // outlets code block removed for concise post purposes

extension FinanceOverviewController: UITableViewDelegate {    
    func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCell.EditingStyle, forRowAt indexPath: IndexPath) {
        if editingStyle == .delete {
            realm.beginWrite()
            realm.delete(tableEntries[indexPath.row])
            try! realm.commitWrite()
        }
    }
}

extension FinanceOverviewController: UITableViewDataSource {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return tableEntries.count
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = financeOverviewTableView.dequeueReusableCell(withIdentifier: "FinanceOverviewCell", for: indexPath) as! FinanceOverviewCell
        let tableData = tableEntries[indexPath.row]

        cell.updateData(name: tableData.name, amount: String(tableData.amount))

        return cell
    }
}

问题出现在视图控制器的cellForRowAtfunc中。不知何故，尽管tableData每次都保存一些适当的内容来添加行，但它只是不添加任何内容。在应用程序屏幕中，我看到了另一行占位符标签

可能是什么问题？我阅读了一些参考资料，也仔细查看了一下，但没有看到任何针对这个案例的特殊解决方案

---

感谢您的支持。

事实上，使用Realm并不困难，我试图复制您的代码，一切正常。我认为它与NotificationToken有关，因为每次更改集合时，NotificationToken都会运行一段代码，我不知道如何更新tableView。我建议您使用此扩展，我已经使用了几个月，这是通过Realm的NotificationToken采用UITableView的最佳方式：

    extension UITableView {
  func applyChanges<T>(changes: RealmCollectionChange<T>) {
    switch changes {
      case .initial: reloadData()
      case .update(let results, let deletions, let insertions, let updates):
        let fromRow = { (row: Int) in return IndexPath(row: row, section: 0) }
        beginUpdates()
        insertRows(at: insertions.map(fromRow), with: .automatic)
        reloadRows(at: updates.map(fromRow), with: .automatic)
        deleteRows(at: deletions.map(fromRow), with: .automatic)
        endUpdates()
      case .error(let error): fatalError("\(error)")
    }
  }
}

---

来源：

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cell.updateData（）代码。

@koen它就在cell类中的单元格出口之后。是的，我现在看到了，谢谢。那么这个方法是用有效数据调用的？您的标签在故事板中连接了吗？@koen是的，调用此方法，然后传递两条数据：条目数量和名称。后两个来源于一系列未解释的条目。那么出口呢？