UIViewController with static table

ExampleViewController.swift

//
//  AddHabitViewController.swift
//  every-habit
//
//  Created by Eugene Cheltsov on 13/02/2019.
//  Copyright © 2019 Eugene Cheltsov. All rights reserved.
//

import UIKit

final class ExampleViewController: StaticTableViewController {
  override func setupUI() {
    super.setupUI()
    tableView.rowHeight = 44
  }

  override func cellsForSections() -> [StaticTableViewControllerSection] {
    return [
      ("First Section", [
        .cell(UITableViewCell()),
      ]),
      ("Second Section", [
        .cell(UITableViewCell()),
      ]),
      ("Third Section", [
        .cellWithHeight(UITableViewCell(), 42),
        .cell(UITableViewCell()),
        .cellWithHeight(UITableViewCell(), 100),
      ]),
    ]
  }
}

StaticTableViewController.swift

import UIKit

enum StaticTableViewControllerCellContainer {
  case cell(UITableViewCell)
  case cellWithHeight(UITableViewCell, CGFloat)
}

typealias StaticTableViewControllerSection = (String, [StaticTableViewControllerCellContainer])

class StaticTableViewController: UIViewController {
  private var cellsForSectionsData: [StaticTableViewControllerSection] = []

  let tableView: UITableView = {
    let view = UITableView(frame: .zero, style: .grouped)
    view.allowsSelection = false
    view.translatesAutoresizingMaskIntoConstraints = false
    return view
  }()

  override func viewDidLoad() {
    super.viewDidLoad()

    cellsForSectionsData = cellsForSections()

    tableView.dataSource = self
    tableView.delegate = self

    setupUI()
  }

  func cellsForSections() -> [StaticTableViewControllerSection] {
    return []
  }

  func setupUI() {
    view.addSubview(tableView)
    tableView.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
    tableView.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
    tableView.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
    tableView.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
  }
}

extension StaticTableViewController: UITableViewDelegate, UITableViewDataSource {
  func numberOfSections(in _: UITableView) -> Int {
    return cellsForSectionsData.count
  }

  func tableView(_: UITableView, numberOfRowsInSection section: Int) -> Int {
    let (_, cells) = cellsForSectionsData[section]
    return cells.count
  }

  func tableView(_: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let (_, cells) = cellsForSectionsData[indexPath.section]
    let container = cells[indexPath.row]

    switch container {
    case let .cell(cell):
      return cell
    case .cellWithHeight(let cell, _):
      return cell
    }
  }

  func tableView(_: UITableView, titleForHeaderInSection section: Int) -> String? {
    let (title, _) = cellsForSectionsData[section]
    return title
  }

  func tableView(_: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    let (_, cells) = cellsForSectionsData[indexPath.section]
    let container = cells[indexPath.row]

    switch container {
    case .cell:
      return tableView.rowHeight
    case let .cellWithHeight(_, height):
      return height
    }
  }
}