How to run code asynchronously using GCD async()
Swift version: 5.1
iOS gives you two ways to run code asynchronously: GCD and performSelector(inBackground:). The first option looks like this:
DispatchQueue.global(qos: .userInitiated).async { [unowned self] in
self.yourCodeHere()
}The .userInitiated quality of service setting is the highest priority after userInteractive. You can also use utility (lower priority) or .background (lowest priority.)
The second option looks like this:
performSelector(inBackground: #selector(yourCodeHere), with: nil)You'll need to replace yourCodeHere with the name of an actual method. If you want to pass a parameter, make sure and use “yourCodeHere:" and provide a value for the with parameter.
SPONSORED Building in-app subscriptions are hard. RevenueCat makes it simple. With their open source SDKs, you can painlessly implement subscriptions for your app in hours, not months.
Sponsor Hacking with Swift and reach the world's largest Swift community!
Available from iOS 4.0 – see Hacking with Swift tutorial 9
Similar solutions…
- How to use Instruments to profile your SwiftUI code and identify slow layouts
- How to create live playgrounds in Xcode
- How to run code when your app is terminated
- How to add drag and drop to your app
- How to do conditional test tear down using addTeardownBlock()
About the Swift Knowledge Base
This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.
