how to resolve DiffableDataSource mulipleCell crash (iOS 13) - ios

Question

I encountered an error during development.
The minimum target is iOS 13.
You want to give different cells for each section using DiffableDataSource.
I don't know why there's an error.
I need your help.
minumum target: iOS 13.0 *
🚨 errorCode 🚨
Thread 1: "unable to dequeue a cell with identifier MuseumItemCell - must register a nib or a class for the identifier or connect a prototype cell in a storyboard"
don't used Storyboard, only programming UI
-- ✅ CODE ✅ --
import UIKit
import SnapKit
final class MuseumViewController: UIViewController {
enum Item: Hashable {
case bannerItem([String])
case numberItem([Int])
}
enum MySection: Int {
case banner
case number
}
var tableView = UITableView()
var dataSource: UITableViewDiffableDataSource<MySection, Item>!
var banners: [String] {
[
"ABCDEFGHIJKL",
"ABCDE",
"A",
]
}
var numbers: [Int] = [100000, 10000, 1000, 100, 10, 10]
override func viewDidLoad() {
super.viewDidLoad()
setupTableView()
fetchDataSource()
fetchSnapShot()
}
func setupTableView() {
view.addSubview(tableView)
tableView.register(MuseumBannerCell.self, forCellReuseIdentifier: MuseumBannerCell.identifier)
tableView.register(MuseumNumberCell.self, forCellReuseIdentifier: MuseumNumberCell.identifier)
tableView.snp.makeConstraints {
$0.edges.equalToSuperview()
}
}
func fetchSnapShot() {
var snapshot = NSDiffableDataSourceSnapshot<MySection, Item>()
snapshot.appendSections([.banner, .number])
snapshot.appendItems([.bannerItem(banners), .numberItem(numbers)])
dataSource.apply(snapshot)
}
func fetchDataSource() {
dataSource = UITableViewDiffableDataSource<MySection, Item>(
tableView: tableView
) { tableView, indexPath, itemIdentifier in
let section = MySection(rawValue: indexPath.section)
switch section {
case .banner:
guard let cell = tableView.dequeueReusableCell(
withIdentifier: MuseumBannerCell.id,
for: indexPath
) as? MuseumBannerCell else { return UITableViewCell() }
cell.backgroundColor = .red
return cell
case .number:
guard let cell = tableView.dequeueReusableCell(
withIdentifier: MuseumNumberCell.id,
for: indexPath
) as? MuseumNumberCell else { return UITableViewCell() }
cell.backgroundColor = .blue
return cell
default:
return UITableViewCell()
}
}
}
}
class MuseumBannerCell: UITableViewCell {
static let id: String = "MuseumBannerCell"
// MARK: - Initialize
override init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
class MuseumNumberCell: UITableViewCell {
static let id: String = "MuseumItemCell"
// MARK: - Initialize
override init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}

Answer 1

In your setupTableView method you set
tableView.register(MuseumBannerCell.self, forCellReuseIdentifier: MuseumBannerCell.identifier)
tableView.register(MuseumNumberCell.self, forCellReuseIdentifier: MuseumNumberCell.identifier)
and later you call
tableView.dequeueReusableCell(withIdentifier: MuseumBannerCell.id, for: indexPath)
Try to register the cells with MuseumBannerCell.id (and MuseumNumberCell.id) since that's the same identifier you use for dequeuing.
tableView.register(MuseumBannerCell.self, forCellReuseIdentifier: MuseumBannerCell.id)
tableView.register(MuseumNumberCell.self, forCellReuseIdentifier: MuseumNumberCell.id)