How to use pull to refresh in Swift?

Pull to refresh is built in iOS. You could do this in swift like

let refreshControl = UIRefreshControl()override func viewDidLoad() {   super.viewDidLoad()   refreshControl.attributedTitle = NSAttributedString(string: "Pull to refresh")   refreshControl.addTarget(self, action: #selector(self.refresh(_:)), for: .valueChanged)   tableView.addSubview(refreshControl) // not required when using UITableViewController}@objc func refresh(_ sender: AnyObject) {   // Code to refresh table view  }

At some point you could end refreshing.

refreshControl.endRefreshing()

A solution with storyboard and Swift:

1. Open your .storyboard file, select a TableViewController in your storyboard and "Enable" the Table View Controller: Refreshing feature in the Utilities.

   

2. Open the associated UITableViewController class and add the following Swift 5 line into the viewDidLoad method.

   self.refreshControl?.addTarget(self, action: #selector(refresh), for: UIControl.Event.valueChanged)

3. Add the following method above the viewDidLoad method

   func refresh(sender:AnyObject){    // Updating your data here...    self.tableView.reloadData()    self.refreshControl?.endRefreshing()}

I would like to mention a PRETTY COOL feature that has been included since iOS 10, which is:

For now, UIRefreshControl is directly supported in each of UICollectionView, UITableView and UIScrollView!

Each one of these views have refreshControl instance property, which means that there is no longer a need to add it as a subview in your scroll view, all you have to do is:

@IBOutlet weak var collectionView: UICollectionView!override func viewDidLoad() {    super.viewDidLoad()    let refreshControl = UIRefreshControl()    refreshControl.addTarget(self, action: #selector(doSomething), for: .valueChanged)    // this is the replacement of implementing: "collectionView.addSubview(refreshControl)"    collectionView.refreshControl = refreshControl}func doSomething(refreshControl: UIRefreshControl) {    print("Hello World!")    // somewhere in your code you might need to call:    refreshControl.endRefreshing()}

Personally, I find it more natural to treat it as a property for scroll view more than add it as a subview, especially because the only appropriate view to be as a superview for a UIRefreshControl is a scrollview, i.e the functionality of using UIRefreshControl is only useful when working with a scroll view; That's why this approach should be more obvious to setup the refresh control view.

However, you still have the option of using the addSubview based on the iOS version:

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