Adding a navigation bar refresh button with timer in swift 4 - ios

Question

I'm trying to add a navigation bar refresh button to update my table view content that coming from JSON and beside that i want my table view keep updating automatically every 5 minutes if the user hasn't pressed the refresh button and changing the button to be an Activity indicator to let the user that is been updating when the table view updating the data
my refresh button IBAction code :
#IBAction func refreshButton(_ sender: Any) {
self.getCoinData()
self.coinTableView.reloadData()
}

Answer 1

Swift 4+
Create Timer & on completion of webservice show the reload icon
class ViewController: UIViewController {
var timer: Timer!
var refreshBarButtonActivityIndicator: UIBarButtonItem!
var refreshBarButton: UIBarButtonItem!
override func viewDidLoad() {
super.viewDidLoad()
barItemSetUp()
}
func barItemSetUp() {
///SettingReloadButton
let image = UIImage(named: "refresh-25")?.withRenderingMode(.alwaysOriginal)
refreshBarButton = UIBarButtonItem(image: image, style: .plain, target: self, action: nil)
///Setting activity Indicator
let activityIndicator: UIActivityIndicatorView = UIActivityIndicatorView.init(activityIndicatorStyle: .gray)
refreshBarButtonActivityIndicator = UIBarButtonItem(customView: activityIndicator)
activityIndicator.startAnimating()
toogleIndicator()
}
deinit {
timer?.invalidate()
}
func toogleIndicator() {
// 5 minutes = 300 seconds //write here 300
timer = Timer.scheduledTimer(timeInterval: 3, target: self, selector: #selector(refreshNow), userInfo: nil, repeats: true)
}
#objc func refreshNow() {
//here i am creating delay for sample purpose
//here write your webservice code on completion of webservice change bar button item
self.navigationItem.rightBarButtonItem = refreshBarButtonActivityIndicator
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 2) {
self.navigationItem.rightBarButtonItem = self.refreshBarButton
}
}
}
Output:-

Answer 2

First add the timer which is refresh data every 5 minutes. At timer, you add the web service.
var timer = Timer()
func runTimer(){
timer = Timer.scheduledTimer(timeInterval: 5, target: self, selector: (#selector(self.updateTimer)), userInfo: nil, repeats: true)
}
func updateTimer() {
self.getCoinData()
self.coinTableView.reloadData()
}
override func viewWillAppear(_ animated: Bool){
runTimer()
}

Answer 3

To reload your UITableView after every 5 minutes, you need to schedule a Timer that executes a block of code every 5 minutes, i.e.
var timer: Timer?
override func viewDidLoad()
{
super.viewDidLoad()
self.timer = Timer.scheduledTimer(withTimeInterval: 300, repeats: true, block: {[weak self] (tt) in
self?.getCoinData()
self?.coinTableView.reloadData()
})
timer?.fire()
}
deinit
{
timer?.invalidate()
}
You can change the time interval according to your requirement. You need to give the time interval in seconds.