RxSwift handle cell actions - mvvm

Question

In my main VC i bind data like this:
let outputs = viewModel.transform(input: inputs)
outputs.posts.drive(view.collectionView.rx.items(cellIdentifier: "postsPagingCollectionViewCell", cellType: PostsPagingCollectionViewCell.self)) { row, post, cell in
cell.post = post
}.disposed(by: disposeBag)
Cell:
var post: Post! {
didSet {
bindViewModel()
}
}
override func bindViewModel() {
guard let viewModel = cellViewModel as? PostsPagingCellViewModel, let cellView = cellView as? PostsPagingCellView else { return }
let _post = BehaviorRelay<Post>(value: post)
let outputs = viewModel.transform(input: .init(post: _post.asObservable()))
outputs.fullName.drive(cellView.fullNameLabel.rx.text).disposed(by: disposeBag)
outputs.nickname.drive(cellView.nickNameLabel.rx.text).disposed(by: disposeBag)
//etc
}
In my cell i have user profile image, and on tap i want to push specific VC. Also, there could be many buttons and i guess i should handle it in mainVC/mainViewModel. How can i do this?

Answer 1

Loading the profile image will require injecting a loader into the cell's view model.
Pushing a view controller generally relies on the tableView.rx.itemSelected operator so the cell isn't involved at all.
For buttons in the cell, it depends on whether the button's action only affects the contents of the cell or if it affects the view controller itself or the contents of other cells.
---UPDATE---
Given what you have said in the comments, I would write the code like this (all the imports are available in CocoaPods or through SPM):
import Cause_Logic_Effect
import EnumKit
import RxCocoa
import RxEnumKit
import RxSwift
final class MyViewController: UIViewController {
#IBOutlet weak var tableView: UITableView!
let disposeBag = DisposeBag()
}
final class MyCell: UITableViewCell {
#IBOutlet weak var pushProfile: UIButton!
#IBOutlet weak var anotherVC: UIButton!
private (set) var disposeBag = DisposeBag()
override func prepareForReuse() {
super.prepareForReuse()
disposeBag = DisposeBag()
}
}
extension MyViewController {
func viewModel() {
let stuff = Observable<[UUID]>.just([UUID(), UUID()]) // build table view here...
let action = PublishSubject<CellAction>()
stuff
.bind(to: tableView.rx.items(cellIdentifier: "Cell", cellType: MyCell.self)) { _, item, cell in
cell.viewModel(item: item)
.bind(to: action)
.disposed(by: cell.disposeBag)
}
.disposed(by: disposeBag)
action
.capture(case: CellAction.profile)
.bind(onNext: presentScene(animated: true) { item in
ProfileViewController.scene { $0.viewModel(item: item) }
})
.disposed(by: disposeBag)
action
.capture(case: CellAction.other)
.bind(onNext: presentScene(animated: true) { item in
OtherViewController.scene { $0.viewModel(item: item) }
})
.disposed(by: disposeBag)
}
}
extension MyCell {
func viewModel(item: UUID) -> Observable<CellAction> {
return Observable.merge(
pushProfile.rx.tap.map(to: CellAction.profile(item)),
anotherVC.rx.tap.map(to: CellAction.other(item))
)
}
}
enum CellAction: CaseAccessible {
case profile(UUID)
case other(UUID)
}
You likely use a heavier view model structure than I do but the key is that there is a PublishSubject in the view controller and the VC presents scenes based on the events output from that subject. The cells push events into the subject.