Generic UITableView with Headers

ViewController.swift

import UIKit

class ViewController: UIViewController {
    
    var hasSearched: Bool = false
    
    let peopleArray = [
        //["primaryImage", "personNext", "personJobTitle", "selectedImage", "section"],
        ["dollarsign.circle", "Ben Shapiro", "Accounts Manager", "dollarsign.circle.fill", "Core Team"],
        ["hammer.circle", "Robert Bokelman", "Operations Manager", "hammer.circle.fill", "Supplemental Team"],
        ["phone.connection", "Sandra Berman", "External Comms", "phone.connection.fill", "Supplemental Team"],
        ["key", "Nicolas Sarcozy", "President", "key.fill", "Core Team"],
        ["person", "Hillary Tate", "Marketing Manager", "person.fill", "Core Team"],
        ["paperplane", "Florence Wong", "Design and Execution", "paperplane.fill", "Core Team"],
        ["doc.badge.gearshape", "Indira Mohamed", "Research and Development", "doc.badge.gearshape.fill", "Core Team"],
        ["person.3", "Philipous Angelos", "International Relations", "person.3.fill", "Core Team"],
        ["alarm.waves.left.and.right", "Simon Graham", "Sales Manager", "alarm.waves.left.and.right.fill", "Core Team"],
        ["cloud.rain", "Tamara Westinghouse", "Environmental Impact", "cloud.rain.fill", "Supplemental Team"],
        ["baseball", "personNext", "personJobTitle", "baseball.fill", "section"],
        ["graduationcap", "personNext", "personJobTitle", "selectedImage", "graduationcap.fill"],
        ["trophy", "personNext", "personJobTitle", "selectedImage", "trophy.fill"],
        ["megaphone", "Forrest Gump", "personJobTitle", "selectedImage", "megaphone.fill"],
    ]
    
    let sectionsArray = ["Core Team", "Supplemental Team"]
    
    let tableView: UITableView = {
        let tableView = UITableView()
        tableView.translatesAutoresizingMaskIntoConstraints = false
        tableView.backgroundView = UIView(frame: tableView.bounds)
        tableView.backgroundView?.backgroundColor = .systemGray5
        tableView.allowsMultipleSelection = true
        tableView.layer.cornerRadius = 20
        tableView.register(UITableViewCell.self, forCellReuseIdentifier: "cell")
        tableView.register(UITableViewHeaderFooterView.self, forHeaderFooterViewReuseIdentifier: "header")
        return tableView }()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        self.view.backgroundColor = .systemGray6
        self.tableView.dataSource = self
        self.view.addSubview(tableView)
        self.tableView.delegate = self
        self.tableViewConfigure() }
    
    private func tableViewConfigure() {
        self.tableView.trailingAnchor.constraint(equalTo: self.view.safeAreaLayoutGuide.trailingAnchor, constant: -10).isActive = true
        self.tableView.leadingAnchor.constraint(equalTo: self.view.safeAreaLayoutGuide.leadingAnchor, constant: 10).isActive = true
        self.tableView.topAnchor.constraint(equalTo: self.view.safeAreaLayoutGuide.topAnchor).isActive = true
        self.tableView.centerXAnchor.constraint(equalTo: self.view.centerXAnchor).isActive = true }
    
    override func viewDidLayoutSubviews() {
        if let rowHeight = self.tableView.cellForRow(at: [0,0])?.contentView.frame.height {
            let numberOfRows = self.tableView.numberOfRows(inSection: 0)
            self.tableView.heightAnchor.constraint(equalToConstant: CGFloat(rowHeight) * CGFloat(numberOfRows))
                .isActive = true
            self.tableView.isScrollEnabled = false }
        else { self.tableView.heightAnchor.constraint(equalToConstant: 540).isActive = true } }
    
    func getSections(with array: [[String]]) -> [String] {
        var sections: [String] = []
        for i in 0..<peopleArray.count {
            if !sections.contains(peopleArray[i].last!) {
                sections.append(peopleArray[i].last!) } }
        return sections }
    
    func getRowsInSections(with array: [[String]]) {
        if !hasSearched {
            var coreTeam = 0
            var supTeam = 0
            for item in array {
                if item.last!.contains("Supplemental Team") { supTeam += 1 }
                else { coreTeam += 1 } } }
        hasSearched = true }

    func setCell(with cell: UITableViewCell, cellForRowAt indexPath: IndexPath, column: Int) -> UITableViewCell? {
        let sectionName = getSections(with: peopleArray)[indexPath.section]
        let sectionItems = peopleArray.filter { $0.last == sectionName }
        let item = sectionItems[indexPath.row]
        var content = cell.defaultContentConfiguration()
        content.image = UIImage(systemName: item[column])
        content.text = item[1]
        content.secondaryText = item[2]
        cell.contentConfiguration = content
        return cell }
    
    func checkMemoryUsage<R>(_ thingToCheck: R, name: String = #function) {
            // You can pass in almost anything - a variable/constant/struct/class/function etc.
        let size = MemoryLayout.size(ofValue: thingToCheck)
        let stride = MemoryLayout.stride(ofValue: thingToCheck)
        let alignment = MemoryLayout.alignment(ofValue: thingToCheck)
        print("\(name).size: \(size)")
        print("\(#function)).stride: \(stride)")
        print("\(type(of: thingToCheck)).alignment: \(alignment)") }
}

extension ViewController: UITableViewDataSource, UITableViewDelegate {
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        var sections = self.getSections(with: peopleArray )
        if section < sections.count {
            let sectionName = sections[section]
            return peopleArray.filter { $0.last == sectionName }.count }
        return 0 }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
        return setCell(with: cell, cellForRowAt: indexPath, column: 0) ?? UITableViewCell() }
    
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        if tableView.cellForRow(at: indexPath)?.isSelected == true {
            let cell = tableView.cellForRow(at: indexPath)!
            cell.selectionStyle = .none
            _ = setCell(with: cell, cellForRowAt: indexPath, column: 3) } }
    
    func tableView(_ tableView: UITableView, didDeselectRowAt indexPath: IndexPath) {
        if tableView.cellForRow(at: indexPath)?.isSelected == false {
            let cell = tableView.cellForRow(at: indexPath)!
            _ = setCell(with: cell, cellForRowAt: indexPath, column: 0) } }

    func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
        return self.getSections(with: peopleArray)[section] }

    func numberOfSections(in tableView: UITableView) -> Int {
        self.getSections(with: peopleArray).count }
    
}