Question

我有以下代码，但我无法填充TableViewCell。请帮忙

这是模型文件Leave.swift

import UIKit

class Leave {
    var startDate: Date!
    var endDate: Date!
    var description: String?


init?(startDate: Date, endDate: Date, description: String) {

    // start date can never ever be later than end date
    if startDate > endDate {
        return nil
    }

    self.startDate = startDate
    self.endDate = endDate
    self.description = description
}
}

我有以下LeaveTableViewController.swift

import UIKit

class LeaveTableViewController: UITableViewController {

var leaves = [Leave]()

private func loadUpcomingLeave() {
    let formatter = DateFormatter()
    formatter.dateStyle = .long
    formatter.timeStyle = .none
    let startDate1 = formatter.date(from: "July 5, 2018")
    let endDate1 = formatter.date(from: "July 6, 2018")
    guard let leave1 = Leave(startDate: startDate1!, endDate: endDate1!, description: "testing") else {
        fatalError("Unable to instantiate leave1")
    }
    let startDate2 = formatter.date(from: "August 5, 2018")
    let endDate2 = formatter.date(from: "August 7, 2018")
    guard let leave2 = Leave(startDate: startDate2!, endDate: endDate2!, description: "testing") else {
        fatalError("Unable to instantiate leave1")
    }
    self.leaves += [leave1, leave2]
}

override func viewDidLoad() {
    super.viewDidLoad()

    // Load the sample data
    loadUpcomingLeave()

    self.tableView.register(LeaveTableViewCell.self, forCellReuseIdentifier: "LeaveTableViewCell")
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
}

override func numberOfSections(in tableView: UITableView) -> Int {
    return 1
}

override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return self.leaves.count
}

override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    //Table view cels are reused and should be dequeued using a cell idenifier
    let cellIdentifier = "LeaveTableViewCell"

    guard let cell = tableView.dequeueReusableCell(withIdentifier: cellIdentifier, for: indexPath) as? LeaveTableViewCell else {
        fatalError("The dequeued cell is not an instance of LeaveTableViewCell.")
    }

    let leave = self.leaves[indexPath.row]
    let df = DateFormatter()
    df.dateStyle = .short
    df.timeStyle = .none
    cell.startDateLabel?.text = df.string(from: leave.startDate)
    cell.endDateLabel?.text = df.string(from: leave.endDate)

    return cell
}
}

当我运行应用程序时，它会显示表格视图但不显示任何单元格数据。我期待2个休假角色，包括开始日期和结束日期。我错过了什么？

Answer 1

案例1 - 检查数据是否存在并从离开CLass

出来

案例2 - 如果数据来自班级

override func viewDidLoad() {
        super.viewDidLoad()

        //Try using this I think nib you created is not getting registered properly 
        self.tableView.register(UINib(nibName: "LeaveTableViewCell", bundle: nil), forCellReuseIdentifier: "LeaveTableViewCell")

        loadUpcomingLeave()
        self.tableView.reloadData()
    }

Answer 2

试试这个

override func viewDidLoad() {
    super.viewDidLoad()

    self.tableView.register(LeaveTableViewCell.self, forCellReuseIdentifier: "LeaveTableViewCell")

  // Load the sample data
    loadUpcomingLeave()

}

private func loadUpcomingLeave() {
    let formatter = DateFormatter()
    formatter.dateStyle = .long
    formatter.timeStyle = .none
    let startDate1 = formatter.date(from: "July 5, 2018")
    let endDate1 = formatter.date(from: "July 6, 2018")
    guard let leave1 = Leave(startDate: startDate1!, endDate: endDate1!, description: "testing") else {
        fatalError("Unable to instantiate leave1")
    }
    let startDate2 = formatter.date(from: "August 5, 2018")
    let endDate2 = formatter.date(from: "August 7, 2018")
    guard let leave2 = Leave(startDate: startDate2!, endDate: endDate2!, description: "testing") else {
        fatalError("Unable to instantiate leave1")
    }
    self.leaves += [leave1, leave2]
self.tableView.reloadData()
}

Answer 3

好吧，似乎删除这一行self.tableView.register(LeaveTableViewCell.self, forCellReuseIdentifier: "LeaveTableViewCell")让TableViewCell工作了我已经在主故事板上设置了标识符

TableViewCell没有出现在TableView中

3 个答案: