[UIKit] MVVM(Combine) 과 UITableViewDiffableDataSource 같이 써보기

Async/Await, MVVM, Combine, TableDiffableDataSource 를 같이 사용해보았다

 

VC 에서 TableView와 DataSource 를 들고 있고 

MVVM 에서 실제 Data 와 FetchRequest 를 요청하는 함수를 실행한다

APIClient 는 실제로 요청을 보낸다

 

// ViewController

	enum Section { case main }

    var tableView: UITableView!
    var dataSource: UITableViewDiffableDataSource<Section, Person>!

    private let viewModel = ViewModel()
    private var cancelBag = Set<AnyCancellable>()
    
	func configureTableView() {
        tableView = UITableView(frame: view.bounds)
        view.addSubview(tableView)
        tableView.register(PersonCell.self, forCellReuseIdentifier: PersonCell.reuseID)
    }
    
    func updateData(on people: [Person]) {
        var snapshot = NSDiffableDataSourceSnapshot<Section, Person>()
        snapshot.appendSections([.main])
        snapshot.appendItems(people)
        DispatchQueue.main.async { [weak self] in
            guard let self = self else { return }
            self.dataSource.apply(snapshot, animatingDifferences: true)
        }
    }

    func configureDataSource() {
        dataSource = UITableViewDiffableDataSource<Section, Person>(tableView: tableView, cellProvider: { tableView, indexPath, person in
            let cell = tableView.dequeueReusableCell(withIdentifier: PersonCell.reuseID) as! PersonCell
            cell.set(person: person)
            return cell
        })
    }

  func setViewModel() {
        viewModel.$people
            .receive(on: DispatchQueue.main)
            .sink { [weak self] people in
                guard let self = self else { return }
                self.updateData(on: people)
            }
            .store(in: &cancelBag)
    }

// ViewModel
	@Published var people: [Person] = []

   func fetchStarwarsPeople() {
        Task {
            do {
                people = try await APIClient().getPeople()
            } catch NetworkError.invalidURL {
                print("Invalid URL ERROR!")
            }
        }
    }