how to stop a dispatchQueue in swift - swift

Question

I have a DispatchQueue for a introViewController that shows a gif for 11 seconds and then display my login page... But also have a button that skip the intro and display the login. When I click it the time still running and when I am navigating in the app goes back to the login when the time ends.
this is my class
class GifClass: UIViewController {
#IBOutlet weak var gifImage: UIImageView!
#IBOutlet weak var skipButton: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
gifImage.loadGif(name: "promed")
DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(11)) {
self.performSegue(withIdentifier: "introLogin", sender: self)
}
}
#IBAction func skip(_ sender: Any) {
performSegue(withIdentifier: "introLogin", sender: self)
}
}
how do I do to stop the time when I click the button?

Answer 1

For this, you can use a DispatchWorkItem. Here is the reference:
https://developer.apple.com/documentation/dispatch/dispatchworkitem
And here is an example of how you could use it in your code:
class GifClass: UIViewController {
#IBOutlet weak var gifImage: UIImageView!
#IBOutlet weak var skipButton: UIButton!
private var workItem: DispatchWorkItem? // Create a private DispatchWorkItem property
override func viewDidLoad() {
super.viewDidLoad()
gifImage.loadGif(name: "promed")
workItem = DispatchWorkItem { // Set the work item with the block you want to execute
self.performSegue(withIdentifier: "introLogin", sender: self)
}
DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(11), execute: workItem!)
}
#IBAction func skip(_ sender: Any) {
workItem?.cancel() // Cancel the work item in the queue so it doesn't run
performSegue(withIdentifier: "introLogin", sender: self)
}
}

Answer 2

I'm not sure if there are best practices here, but I would consider doing what you are doing with a Timer rather than the DispatchQueue.
class GifClass: UIViewController {
#IBOutlet weak var gifImage: UIImageView!
#IBOutlet weak var skipButton: UIButton!
var timer = Timer()
override func viewDidLoad() {
super.viewDidLoad()
gifImage.loadGif(name: "promed")
timer = Timer.scheduledTimer(timeInterval: 11, target: self, selector: #selector(timerAction), userInfo: nil, repeats: false)
}
#objc func timerAction() {
performSegue(withIdentifier: "introLogin", sender: self)
}
#IBAction func skip(_ sender: Any) {
timer.invalidate()
performSegue(withIdentifier: "introLogin", sender: self)
}
}

Answer 3

You don't stop the queue. Instead, when the task that you dispatched starts executing, it needs to check its context and do the right thing (often: nothing) if the context has changed.