Pull to refresh in UICollectionView in ViewController

Question

I used the following code at a UICollectionViewController

override func viewDidLoad() {            

    self.collectionView!.alwaysBounceVertical = true
    let refresher = UIRefreshControl()
    refresher.addTarget(self, action: "refreshStream", forControlEvents: .ValueChanged)

    refreshControl = refresher
    collectionView!.addSubview(refreshControl!)
}

func refreshStream() {

    print("refresh")
    self.collectionView?.reloadData()

    refreshControl?.endRefreshing()

}

Now I need it to work with a UICollectionView inside a UIViewController and I googled for an hour now but can't get it working. I appreciate any help.

Isn't it work? http://stackoverflow.com/questions/14678727/uirefreshcontrol-on-uicollectionview-only-works-if-the-collection-fills-the-heig — markov, Feb 12 '16 at 12:16
The main code is objective c and the swift comments gets me a lot issues: — David Seek, Feb 12 '16 at 12:19
this error says the the collectionview is not a member class in current class , so do like in view didload `self.collectionView.registerNib(UINib(nibName: "xxxx", bundle: NSBundle.mainBundle()), forCellWithReuseIdentifier: "xxxx")` — Anbu.Karthik, Feb 12 '16 at 12:24
well, if I enter that code, I'm again getting "Ambiguous reference to member 'collectionView'" — David Seek, Feb 12 '16 at 12:27
my header is: class NewBlogViewController: UIViewController, UICollectionViewDelegateFlowLayout, UICollectionViewDataSource {..} — David Seek, Feb 12 '16 at 12:27
see this for iOS 10 http://stackoverflow.com/questions/19483511/uirefreshcontrol-with-uicollectionview-in-ios7/37865309#37865309 — Anish Parajuli 웃, Jun 16 '16 at 17:04

Nagarjun · Answer 1 · 2019-09-17T11:39:44.173

69

New swift code changed in calling action method you could do rewrite like this

@IBOutlet weak var collectionView: UICollectionView!

var refresher:UIRefreshControl!

override func viewDidLoad() {

   super.viewDidLoad()

    self.refresher = UIRefreshControl()
    self.collectionView!.alwaysBounceVertical = true
    self.refresher.tintColor = UIColor.red
    self.refresher.addTarget(self, action: #selector(loadData), for: .valueChanged)
    self.collectionView!.addSubview(refresher)
}

func loadData() {
   self.collectionView!.refreshControl.beginRefreshing()
   //code to execute during refresher
       .
       .
       .
   stopRefresher()         //Call this to stop refresher
 }

func stopRefresher() {
   self.collectionView!.refreshControl.endRefreshing()
 }

edited Sep 17 '19 at 11:39

answered Jun 13 '16 at 13:22

Nagarjun

5,811
5
28
47

Thank you, but "var refreshControl:UIRefreshControl!" need change to "var refresher:UIRefreshControl!" – Ego Slayer Aug 07 '16 at 15:50
11

rather than ```addSubview(refresher)```, the swift3 way of adding this refresher to a collection is: ```self.collectionView!.refreshControl = refresher self.collectionView!.refreshControl.beginRefreshing() self.collectionView!.refreshControl.endRefreshing()``` – Achintya Ashok Feb 22 '17 at 23:26
3

@KingChintz collectionView.refreshControl is only available in iOS10. addSubview works across more version. – Q Liu Mar 25 '17 at 06:13
Doesn't `let refresher = UIRefreshControl()` create a local instance of `UIRefreshControl` for `viewDidLoad` only? shouldn't it be `self.refresher = UIRefreshControl()` The code as is wouldn't run the stopRefresher correctly – Reza Shirazian Jun 17 '17 at 17:19

score 20 · Answer 2 · edited Mar 15 '19 at 23:48

20

var refreshControl:UIRefreshControl!

override func viewDidLoad() {
    super.viewDidLoad()
      self.refreshControl = UIRefreshControl()
      self.refreshControl.attributedTitle = NSAttributedString(string: "Pull to refresh")
     self.refreshControl.addTarget(self, action: #selector(PricingPlansCollectionViewController.reload), for: .valueChanged)
      collectionView!.addSubview(refreshControl)
}

 func refresh(sender:AnyObject)
  {
    //DO 
  }

edited Mar 15 '19 at 23:48

Romulo BM

561
6
15

answered Feb 12 '16 at 13:37

Subin K Kuriakose

843
7
17

Your Code wants me to put in an semicolone betweet "ValueChanged) collectionView!" ----> Consecutive statements on a line must be separated by ';' – David Seek Feb 12 '16 at 13:43
You should be setting the refresh control object to the `refreshControl` property of your collectionView [per the docs](https://developer.apple.com/documentation/uikit/uirefreshcontrol) – Samy Aug 16 '19 at 05:31

score 16 · Answer 3 · answered Apr 16 '19 at 08:49

Swift 5 solution

As @fishspy already mentioned, that's the way to put your collection view inside a view controller, but I'm gonna share also how to connect your refresh control to the collection view in a cleaner way.

Since iOS 10 there's a dedicated property for the refresh control. Apart of that, I'd also recommend to directly initialise your refresh control as a property, declaring it private and doing the following things:

@IBOutlet private weak var collectionView: UICollectionView!

private let refreshControl = UIRefreshControl()

override func viewDidLoad() {

    super.viewDidLoad()

    refreshControl.addTarget(self, action: #selector(didPullToRefresh(_:)), for: .valueChanged)
    collectionView.alwaysBounceVertical = true
    collectionView.refreshControl = refreshControl // iOS 10+
}

@objc
private func didPullToRefresh(_ sender: Any) {
    // Do you your api calls in here, and then asynchronously remember to stop the
    // refreshing when you've got a result (either positive or negative)
    refreshControl.endRefreshing()
}

I've never seen an horizontal pull-to-refresh honestly, so no as far as I know — Alessandro Francucci, Jun 17 '19 at 09:06
For anyone who needs this, I found an answer here: https://stackoverflow.com/questions/56614319/is-it-possible-to-add-a-drag-to-reload-horizontally-for-a-collection-view — , Jun 17 '19 at 17:14

score 13 · Accepted Answer · answered Feb 12 '16 at 13:58

13

From the storyboard, you need to link the collection view to the appropriate controller file, using Ctrl + Drag from the collection view object. It needs to be linked via an @IBOutlet.

Also, you should Ctrl + Drag from the collection view to the view controller object on the storyboard and select Data Source and Delegate so that the collection view is correctly linked.

Let me know if this helps or if I have misunderstood your situation.

answered Feb 12 '16 at 13:58

fishspy

146
3

hell yeah! thank you pal. the outlet dit it. thank you! – David Seek Feb 12 '16 at 14:03

Haseeb Javed · Answer 5 · 2020-11-12T09:12:59.460

1

private let refreshControl = UIRefreshControl()

refreshControl.addTarget(self, action: #selector(youFunction), for: .valueChanged)
   
refreshControl.attributedTitle = NSAttributedString(string: "Fetching Data ...", attributes: nil)

DispatchQueue.main.async {
       self.refreshControl.endRefreshing()
       yourCollectionViewOrTableView.reloadData()
 }

edited Nov 12 '20 at 09:12

answered Sep 19 '19 at 06:26

Haseeb Javed

856
8
10

score 1 · Answer 6 · answered Feb 25 '21 at 06:32

For me, i had:

func setupCollectionView(){
      self.refreshControl = UIRefreshControl()
      self.refreshControl.attributedTitle = NSAttributedString(string: "Refreshing content...")
      self.refreshControl.addTarget(self, action: #selector(self.reload), for: .valueChanged)
      collectionView!.addSubview(refreshControl)
}

It still wasn't working (I believe i had constraints preventing it somehow), so i added:

collectionView.alwaysBounceVertical = true

then all was good. Just in case someone else is facing the same issue.

For a better understanding, the full implementation

@IBOutlet private weak var collectionView: UICollectionView!
let refreshControl = UIRefreshControl()

override func viewDidLoad() {
 super.viewDidLoad()
 setupCollectionView()
}

func setupCollectionView(){
      collectionView.delegate = self
      collectionView.dataSource = self
      collectionView.alwaysBounceVertical = true
      self.refreshControl = UIRefreshControl()
      self.refreshControl.attributedTitle = NSAttributedString(string: "Refreshing content...")
      self.refreshControl.addTarget(self, action: #selector(self.refresh), for: .valueChanged)
      collectionView!.addSubview(refreshControl)
}

 @objc func refresh(_ sender:AnyObject) {
    //do refreshing stuff
}

Pull to refresh in UICollectionView in ViewController

6 Answers6

Swift 5 solution