Pull to refresh not performing refreshing function?

Question

I am coding an app and have a set up queryAndAppend functions that query a DB and append the info pulled to a set of arrays (which are then used to iterate through cells in a table view). The query functions work appropriately as they are called in the viewDidLoad(). I want a pull to refresh function to additionally call the functions (and thus update the table cells) but it is not working properly. Here is the relevant code:

var refreshControl = UIRefreshControl()
    override func viewDidLoad() {
            super.viewDidLoad()

            myQueryandAppend(completion: {
                self.tableView.reloadData()
            })

            upComingQueryandAppend(completion: {
                self.tableView.reloadData()
            })

            refreshControl = UIRefreshControl()
            refreshControl.attributedTitle = NSAttributedString(string: "Pull to refresh")
            refreshControl.addTarget(self, action: #selector(MainPageVC.refresh(_:)), for: UIControlEvents.valueChanged)

        }
        func refresh(_ sender: AnyObject){

            myQueryandAppend(completion: {
                self.tableView.reloadData()
                self.refreshControl.endRefreshing()

            })
            upComingQueryandAppend(completion:{

                self.tableView.reloadData()
                self.refreshControl.endRefreshing()

            })

        }

Not entirely sure why its not working as I have a very similar set up in a different view controller (with a different query/append function) that works properly with pull to refresh.

Answer 1

If the class is a UIViewController but not a UITableViewController, you need to add the refreshControl as a subview to the tableView manually:

tableView.addSubview(refreshControl)

So, viewDidLoad() should looks like this:

override func viewDidLoad() {
    super.viewDidLoad()


    myQueryandAppend(completion: {
        self.tableView.reloadData()
    })

    upComingQueryandAppend(completion: {
        self.tableView.reloadData()
    })

    refreshControl = UIRefreshControl()
    refreshControl.attributedTitle = NSAttributedString(string: "Pull to refresh")
    refreshControl.addTarget(self, action: #selector(MainPageVC.refresh(_:)), for: UIControlEvents.valueChanged)
    // here is the extra job!
    tableView.addSubview(refreshControl)
}