Multiple Cell Types example based on episode 6 of talk.objc.io in response to question in episode 9

objcio S01E06 Multiple Cell Types.swift

import UIKit
import XCPlayground


struct Episode {
	var title: String
}

struct Season {
	var number: Int
	var title: String
}


protocol Reusable: class {
	static var reuseIdentifier: String { get }
}


struct Row {
	init<Item, Cell: UITableViewCell where Cell: Reusable>(item: Item, reuseIdentifier: String, configure: (Cell, Item) -> (), didSelect: ((Item) -> ())? = nil) {
		self.cell = { (tableView, indexPath) in
			let cell = tableView.dequeueReusableCellWithIdentifier(reuseIdentifier, forIndexPath: indexPath) as! Cell
			configure(cell, item)
			return cell
		}
		self.didSelect = { didSelect?(item) }
	}

	let cell: (from: UITableView, at: NSIndexPath) -> UITableViewCell
	let didSelect: () -> ()
}


final class RowsViewController: UITableViewController {
	var rows: [Row] = []

	init(rows: [Row], cellTypes: [Reusable.Type]) {
		super.init(style: .Plain)
		cellTypes.forEach { (reusable) in
			tableView.registerClass(reusable, forCellReuseIdentifier: reusable.reuseIdentifier)
		}
		self.rows = rows
	}

	required init?(coder aDecoder: NSCoder) {
		fatalError("init(coder:) has not been implemented")
	}

	override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
		rows[indexPath.row].didSelect()
	}

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

	override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
		return rows[indexPath.row].cell(from: tableView, at: indexPath)
	}
}


let sampleEpisodes = [
	Episode(title: "First Episode"),
	Episode(title: "Second Episode"),
	Episode(title: "Third Episode")
]

let sampleSeasons = [
	Season(number: 1, title: "Season One"),
	Season(number: 2, title: "Season Two")
]


final class SeasonCell: UITableViewCell, Reusable {
	static let reuseIdentifier = "SeasonCell"

	override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
		super.init(style: .Value1, reuseIdentifier: reuseIdentifier)
	}

	required init?(coder aDecoder: NSCoder) {
		fatalError("init(coder:) has not been implemented")
	}
}


final class CastCell: UITableViewCell, Reusable {
	static let reuseIdentifier = "CastCell"

	override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
		super.init(style: .Value1, reuseIdentifier: reuseIdentifier)
		backgroundColor = .lightGrayColor()
	}

	required init?(coder aDecoder: NSCoder) {
		fatalError("init(coder:) has not been implemented")
	}
}


let episodeRows = sampleEpisodes.map { (episode) in
	Row(item: episode, reuseIdentifier: SeasonCell.reuseIdentifier, configure: { (cell: SeasonCell, episode) in
		cell.textLabel?.text = episode.title
	})
}


let nc = UINavigationController()

let pushEpisodes: (Season) -> () = { (season) in
	let episodesVC = RowsViewController(rows: episodeRows, cellTypes: [SeasonCell.self])
	episodesVC.title = season.title
	nc.pushViewController(episodesVC, animated: true)
}


let seasonRows = sampleSeasons.map {
	Row(item: $0,
		reuseIdentifier: SeasonCell.reuseIdentifier,
		configure: { (cell: SeasonCell, season) in
			cell.textLabel?.text = season.title
			cell.detailTextLabel?.text = "\(season.number)"
		},
		didSelect: pushEpisodes)
}
let otherRow = Row(item: "Cast", reuseIdentifier: CastCell.reuseIdentifier, configure: { (cell: CastCell, text) in
	cell.textLabel?.text = text
})
let seasonsVC = RowsViewController(rows: seasonRows + [otherRow], cellTypes: [SeasonCell.self, CastCell.self])
seasonsVC.tableView.reloadData()
seasonsVC.title = "Seasons"
nc.viewControllers = [seasonsVC]


nc.view.frame = CGRect(x: 0, y: 0, width: 320, height: 480)
XCPlaygroundPage.currentPage.liveView = nc.view

I have adapted my solution of supporting multiple cell types in one table view controller to the code from: https://github.com/objcio/S01E06-generic-table-view-controllers in response to the question posed in https://talk.objc.io/episodes/S01E09-q-a. My solution involves extracting the cell configuring logic out of the table view controller by introducing a Row type. This allows the table view controller to be non-generic and therefore not restricted to one cell type.