Delay Actions in Swift

dispatch_after() is the standard way of delaying actions.

indicator.startAnimating()let delay = 4.5 * Double(NSEC_PER_SEC)let time = dispatch_time(DISPATCH_TIME_NOW, Int64(delay))dispatch_after(time, dispatch_get_main_queue()) {    indicator.stopAnimating()}

See: dispatch_after - GCD in swift?

Update for Swift 3.0

indicator.startAnimating()let delay = Int(4.5 * Double(1000))DispatchQueue.main.after(when: .now() + .milliseconds(delay)) {    indicator.stopAnimating()}

However, in the spirit of Swift 3.0, I think extending DispatchQueue would be a better solution.

extension DispatchQueue {    func delay(_ timeInterval: TimeInterval, execute work: () -> Void) {        let milliseconds = Int(timeInterval * Double(1000))        after(when: .now() + .milliseconds(milliseconds), execute: work)    }}

This leaves us with a very nice

indicator.startAnimating()DispatchQueue.main.delay(4.5) {    indicator.stopAnimating()}

Update 2

Digging into the Xcode 8.0 beta, I found public func +(time: DispatchTime, seconds: Double) -> DispatchTime. So, I guess this is valid…

indicator.startAnimating()DispatchQueue.main.after(when: .now() + 4.5) {    indicator.stopAnimating()}

I don't think there is a need to extend DispatchQueue for something this clean already.

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Update for Swift 3.1

There is new syntax for Swift 3.1. They just likes to change things don't they.

indicator.startAnimating()DispatchQueue.main.asyncAfter(deadline: .now() + 4.5) {    indicator.stopAnimating()}

With the updated Swift 3 syntax this becomes

DispatchQueue.main.asyncAfter(deadline: .now() + 4.5) {    indicator.stopAnimating()}

Here is a cleaner and more expressive code to do this using Swift 3.1 and Grand Central Dispatch:

Swift 3.1:

indicator.startAnimating()// Runs after 1 second on the main queue.DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(1) ) {     indicator.stopAnimating()}

Also .seconds(Int), .microseconds(Int) and .nanoseconds(Int) may be used for the time.