Enumerated UITableViewCell identifier example

TableViewDataSourceExample.swift

import UIKit

/// Protocol to be implemented by table view cell identifier enums
protocol TableViewCellIdentifier {
    var identifierString: String { get }
}

/// Extension to provide default impementation for RawRepresentable String enums
extension TableViewCellIdentifier where Self: RawRepresentable, Self.RawValue == String {
    var identifierString: String {
        return self.rawValue
    }
}

/// Table View section type
enum SectionType<T: TableViewCellIdentifier> {
    case Static([T])
    case Dynamic(TableViewDelegateDataSource)
}

/// Protocol for objects implementing both UITableViewDataSource and UITableViewDelegate
protocol TableViewDelegateDataSource: UITableViewDelegate, UITableViewDataSource { }

// Main tableview delegate/dataSource object
class DataSource: NSObject, TableViewDelegateDataSource {
    enum CellIdentifier: String, TableViewCellIdentifier {
        case Header
        case Main
        case FirstDetail
        case SecondDetail
    }

    typealias Section = SectionType<CellIdentifier>

    let sections: [DataSource.Section] = [
        .Static([.Header]),
        .Dynamic(OtherDataSource()),
        .Static([.Main,.FirstDetail,.SecondDetail])
    ]

    func numberOfSectionsInTableView(tableView: UITableView) -> Int {
        return sections.count
    }

    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        assert(section < sections.count)
        switch sections[section] {
        case .Static(let rows):
            return rows.count
        case .Dynamic(let dataSource):
            return dataSource.tableView(tableView, numberOfRowsInSection: section)
        }
    }

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        assert(indexPath.section < sections.count)
        switch sections[indexPath.section] {
        case .Static(let rows):
            let row = rows[indexPath.row]
            let cell = tableView.dequeueReusableCellWithIdentifier(row.rawValue, forIndexPath: indexPath)
            switch row {
            case .Header:
                cell.textLabel?.text = "Hello, world!"
            case .Main:
                cell.textLabel?.text = "Lorem ipsum dolor sit amet."
            case .FirstDetail:
                cell.textLabel?.text = "Aliquam ut orci turpis. Maecenas mauris ligul"
                cell.detailTextLabel?.text = "Integer sed mi id risus fermentum dignissim"
            case .SecondDetail:
                cell.textLabel?.text = "Lorem ipsum dolor sit amet."
                cell.detailTextLabel?.text = "Cras dui lorem"
            }
            return cell
        case .Dynamic(let dataSource):
            return dataSource.tableView(tableView, cellForRowAtIndexPath: indexPath)
        }
    }

    func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
        switch sections[indexPath.section] {
            case .Static(_):
                return
            case .Dynamic(let delegate):
                delegate.tableView?(tableView, didSelectRowAtIndexPath: indexPath)
        }
    }
}

/// Child data source to be used with `DataSource` or in its own view controller
class OtherDataSource: NSObject, TableViewDelegateDataSource {
    let details = ["thing one", "thing two"]

    func numberOfSectionsInTableView(tableView: UITableView) -> Int {
        return 1
    }

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

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCellWithIdentifier(DataSource.CellIdentifier.SecondDetail.rawValue, forIndexPath: indexPath)
        cell.textLabel?.text = details[indexPath.row]
        return cell
    }

    func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
        cellSelectionAction(indexPath.row)
    }

    func cellSelectionAction(index: Int) {
        // do something
    }
}