ios - 如何返回 TableViewController (Swift) 的填充版本？

Question

我正在 Xcode 9.3 中构建一个适用于 iOS 的房间预订应用程序。 这是基本布局:

• 第一个 TableViewController(TVC1):开始为空。按“+”会弹出
• 第二个 TableViewController(TVC2)，有许多字段需要填写。

按下 TVC2 上的“完成”按钮后，我将返回 TVC1，其中现在有一个包含插入详细信息的单元格(字幕样式)。

我现在想点击所述单元格并返回 TVC2 以检查或修改数据。
我已经创建了 segue，但点击后我得到的 TVC2 版本与按“+”时得到的版本相同，而不是填充的版本。

我做错了什么？

这是我需要编辑的与 TVC1 相关的代码:

import UIKit

class RegistrationTableViewController: UITableViewController {
    var registrations: [Registration] = []

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

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

// MARK: - Table view data source

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

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

override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: "RegistrationCell", for: indexPath)

    let registration = registrations[indexPath.row]
    let dateFormatter = DateFormatter()
    dateFormatter.dateStyle = .short

    cell.textLabel?.text = registration.firstName + " " + registration.lastName
    cell.detailTextLabel?.text = dateFormatter.string(from: registration.checkInDate) + " - " + registration.roomType.name

    return cell
}

@IBAction func unwindFromAddRegistration(unwindSegue: UIStoryboardSegue) {
    guard let addRegistrationTableViewController = unwindSegue.source as? AddRegistrationTableViewController,
        let registration = addRegistrationTableViewController.registration else { return }

    registrations.append(registration)
    tableView.reloadData()
}

// MARK: Challenge.
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    tableView.deselectRow(at: indexPath, animated: true)
}

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "ViewReservationDetails" {


    }
}  

这里是 (TVC2) 的代码，以便您或多或少地拥有所有可用的应用程序。

import UIKit

class AddRegistrationTableViewController: UITableViewController, SelectRoomTypeTableViewControllerDelegate {
// MARK: Properties
let checkInDatePickerCellIndexPath = IndexPath(row: 1, section: 1)
let checkOutDatePickerCellIndexPath = IndexPath(row: 3, section: 1)

var isCheckInDatePickerShown: Bool = false {
    didSet {
        checkInDatePicker.isHidden = !isCheckInDatePickerShown
    }
}
var isCheckOutDatePickerShown: Bool = false {
    didSet {
        checkOutDatePicker.isHidden = !isCheckOutDatePickerShown
    }
}

var roomType: RoomType?
var registration: Registration? {
    guard let roomType = roomType else { return nil }

    let firstName = firstNameTextField.text ?? ""
    let lastName = lastNameTextField.text ?? ""
    let email = emailTextField.text ?? ""
    let checkInDate = checkInDatePicker.date
    let checkOutDate = checkOutDatePicker.date
    let numberOfAdults = Int(numberOfAdultsStepper.value)
    let numberOfChildren = Int(numberOfChildrenStepper.value)
    let hasWifi = wifiSwitch.isOn

    return Registration(firstName: firstName, lastName: lastName, emailAddress: email, checkInDate: checkInDate, checkOutDate: checkOutDate, numberOfAdults: numberOfAdults, numberOfChildren: numberOfChildren, roomType: roomType, wifi: hasWifi)
}

var selectedItem: Registration?

// MARK: Outlets
@IBOutlet weak var firstNameTextField: UITextField!
@IBOutlet weak var lastNameTextField: UITextField!
@IBOutlet weak var emailTextField: UITextField!

@IBOutlet weak var checkInDateLabel: UILabel!
@IBOutlet weak var checkInDatePicker: UIDatePicker!
@IBOutlet weak var checkOutDateLabel: UILabel!
@IBOutlet weak var checkOutDatePicker: UIDatePicker!

@IBOutlet weak var numberOfAdultsLabel: UILabel!
@IBOutlet weak var numberOfAdultsStepper: UIStepper!
@IBOutlet weak var numberOfChildrenLabel: UILabel!
@IBOutlet weak var numberOfChildrenStepper: UIStepper!

@IBOutlet weak var roomTypeLabel: UILabel!

@IBOutlet weak var wifiSwitch: UISwitch!

// MARK: Actions
@IBAction func datePickerValueChanged(_ sender: UIDatePicker) {
    updateDateViews()
}
@IBAction func stepperValueChanged(_ sender: UIStepper) {
    updateNumberOfGuests()
}
@IBAction func wifiSwitchChanged(_ sender: UISwitch) {
    // implemented later
}
@IBAction func cancelButtonTapped(_ sender: Any) {
    dismiss(animated: true, completion: nil)
}
// MARK: Methods
func updateDateViews() {
    checkOutDatePicker.minimumDate = checkInDatePicker.date.addingTimeInterval(86400)

    let dateFormatter = DateFormatter()
    dateFormatter.dateStyle = .medium

    checkInDateLabel.text = dateFormatter.string(from: checkInDatePicker.date)
    checkOutDateLabel.text = dateFormatter.string(from: checkOutDatePicker.date)
}

func updateNumberOfGuests() {
    numberOfAdultsLabel.text = "\(Int(numberOfAdultsStepper.value))"
    numberOfChildrenLabel.text = "\(Int(numberOfChildrenStepper.value))"
}

func updateRoomType() {
    if let roomType = roomType {
        roomTypeLabel.text = roomType.name
    } else {
        roomTypeLabel.text = "Not Set"
    }
}

func didSelect(roomType: RoomType) {
    self.roomType = roomType
    updateRoomType()
}

override func viewDidLoad() {
    super.viewDidLoad()

    let midnightToday = Calendar.current.startOfDay(for: Date())
    checkInDatePicker.minimumDate = midnightToday
    checkInDatePicker.date = midnightToday

    updateDateViews()
    updateNumberOfGuests()
    updateRoomType()
}

// MARK: TableView Data
override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    switch (indexPath.section, indexPath.row) {
    case (checkInDatePickerCellIndexPath.section, checkInDatePickerCellIndexPath.row):
        if isCheckInDatePickerShown {
            return 216.0
        } else {
            return 0.0
        }
    case (checkOutDatePickerCellIndexPath.section, checkOutDatePickerCellIndexPath.row):
        if isCheckOutDatePickerShown {
            return 216.0
        } else {
            return 0.0
        }
    default:
        return 44.0
    }
}

override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    tableView.deselectRow(at: indexPath, animated: true)

    switch (indexPath.section, indexPath.row) {
    case (checkInDatePickerCellIndexPath.section, checkInDatePickerCellIndexPath.row - 1):
        if isCheckInDatePickerShown {
            isCheckInDatePickerShown = false
        } else if isCheckOutDatePickerShown {
            isCheckOutDatePickerShown = false
            isCheckInDatePickerShown = true
        } else {
            isCheckInDatePickerShown = true
        }

        tableView.beginUpdates()
        tableView.endUpdates()

    case (checkOutDatePickerCellIndexPath.section, checkOutDatePickerCellIndexPath.row - 1):
        if isCheckOutDatePickerShown {
            isCheckOutDatePickerShown = false
        } else if isCheckInDatePickerShown {
            isCheckInDatePickerShown = false
            isCheckOutDatePickerShown = true
        } else {
            isCheckOutDatePickerShown = true
        }

        tableView.beginUpdates()
        tableView.endUpdates()

    default:
        break
    }
}

// MARK: Navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "SelectRoomType" {
        let destinationViewController = segue.destination as? SelectRoomTypeTableViewController
        destinationViewController?.delegate = self
        destinationViewController?.roomType = roomType
    }
}

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

}

本教程的挑战是从这里开始: “使用 segue 更新 RegistrationTableViewController(TVC1)，允许用户在 AddRegistrationTableViewController(TVC2) 中选择和查看注册详细信息。

希望这有助于提供正确的解决方案。

Answer 1

在 TVC2 屏幕中创建一个属性，例如 selectedItem。

var selectedItem: Registration?

修改准备单元格...

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {

   if segue.identifier == "ViewReservationDetails" {

         let sourceCell = sender as! UITableViewCell

         if let indexPath = tableView.indexPath(for: sourceCell) {

            if let dest = segue.destination as? <#Destination view controller#> {

              dest.selectedItem = registrations[indexPath.row]
            }
         }
    }
 }

最后，在目标 View Controller (具有 TVC2)中，您需要检查 selectedItem 并在 viewDidLoad: 或任何地方分配值。

 override func viewDidLoad() {
    super.viewDidLoad()

    if let  item = selectedItem {
        //here set value as you want to views

     }
}