Why does UIActivityIndicatorView only animate the first time it is visible? - ios

Question

I change the navigation bar title depending on the network status, when there is no connection I display as UIActivityIndicatorView, along side "Waiting for network". This works perfectly the very first time I turn off network connectivity, when I disable it for the second time, "Waiting for network" and the Activity indicator appear, however, it doesn't animate.
override func viewDidLoad() {
label.text = "Waiting for network"
label.font = UIFont.systemFont(ofSize: 17)
label.textColor = .black
containerView.addSubview(self.activityIndicator)
containerView.addSubview(label)
label.translatesAutoresizingMaskIntoConstraints = false
self.activityIndicator.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
self.activityIndicator.centerYAnchor.constraint(equalTo: containerView.centerYAnchor),
self.activityIndicator.leadingAnchor.constraint(equalTo: containerView.leadingAnchor),
label.centerYAnchor.constraint(equalTo: containerView.centerYAnchor),
label.leadingAnchor.constraint(equalTo: self.activityIndicator.trailingAnchor, constant: 8),
containerView.widthAnchor.constraint(equalTo: label.widthAnchor, constant: self.activityIndicator.frame.width + 8)
])
super.viewDidLoad()
}
func onUpdate(_ isConnected: Bool) {
print("isInternetConnected changed to: \(isConnected)")
if isConnected {
DispatchQueue.main.async {
self.navigationItem.titleView = nil
self.activityIndicator.stopAnimating()
self.navigationItem.title = "Chats"
}
} else {
DispatchQueue.main.async {
self.navigationItem.titleView =
self.containerView
self.activityIndicator.startAnimating()
}
}
}
let activityIndicator: UIActivityIndicatorView = {
let activityIndicator = UIActivityIndicatorView()
activityIndicator.style = .medium
activityIndicator.hidesWhenStopped = true
activityIndicator.color = .black
activityIndicator.startAnimating()
return activityIndicator
}()

Answer 1

You need to start animation by calling self.activityIndicator.startAnimating(), as you stop it when isConnected is true
if isConnected {
DispatchQueue.main.async {
self.navigationItem.titleView = nil
if self.activityIndicator.isAnimating {
self.activityIndicator.stopAnimating()
}
self.navigationItem.title = "Chats"
}
} else {
DispatchQueue.main.async {
self.navigationItem.titleView = self.containerView
if !self.activityIndicator.isAnimating {
self.activityIndicator.startAnimating() // <<< --- here
}
}
}