How to implement refresh control for table views as common function

Question

I've many VCs in which I've Table Views where I add refresh control. It's a copy paste in each VC. I wanted to move refresh control to a common function in extension but I can't figure out how to do it. If there is any other way to avoid copy n paste then please give me some pointers.

Following is my typical refresh control implementation in a VC.swift

class MyVC: UIViewController {

    lazy var refreshControl: UIRefreshControl = {
        let refreshControl = UIRefreshControl()
        refreshControl.addTarget(self, action: #selector(refresh(_:)), for: UIControlEvents.valueChanged)
         return refreshControl
    }()

    override func viewDidLoad() {
        super.viewDidLoad()

        if #available(iOS 10.0, *) {
            messagesTable.refreshControl = refreshControl
        } else {
            messagesTable.addSubview(refreshControl)
       }
    }

    @objc func refresh(_ refreshControl: UIRefreshControl) {
        fetchData()
    }
}

Answer 1

If all of your ViewController should has TableView as well as RefreshControl inside, you can create one superclass (you can keep MyVC) for all of these Controllers.

class MyVC: UIViewController {

    lazy var refreshControl: UIRefreshControl = {
        let refreshControl = UIRefreshControl()
        refreshControl.addTarget(self, action: #selector(refresh(_:)), for: UIControlEvents.valueChanged)
        return refreshControl
    }()

    func addRefreshControl(to tableView: UITableView) {
        if #available(iOS 10.0, *) {
            tableView.refreshControl = refreshControl
        } else {
            tableView.addSubview(refreshControl)
        }
    }

    @objc func refresh(_ refreshControl: UIRefreshControl) {
        fetchData()
    }

    func fetchData() {
    }
}

then make your other Controllers subclasses of MyVC and when you need to add RefreshControl, call addRefreshControl with controller's TableView as parameter

class MessageVC: MyVC {

    @IBOutlet weak var messageTable: UITableView!
    ...
    override func viewDidLoad() {
        super.viewDidLoad()
        ...
        addRefreshControll(to: messageTable)
    }
    ...
    override func fetchData() {
        // what should happen when refresh control changes its value
    }
}

... also you can override fetchData method and declare what should happen when refresh control changes its value