Project 9: Grand Central Dispatch

Written by Paul Hudson    @twostraws

Description: Learn how to run complex tasks in the background with GCD.

• Setting up

• Why is locking the UI bad?

• GCD 101: async()

• Back to the main thread: DispatchQueue.main

• Easy GCD using performSelector(inBackground:)

• Wrap up

Need help?

I put together answers for almost 600 of the most frequently asked questions I received from readers into one place: the Swift 4 Knowledge Base. It answers basic and advanced questions, and provides lots of free code you can re-use however you please. If you hit problems, try searching there first.

If you're still having problems, you can post to the Hacking with Swift subreddit where you can expect an answer fairly quickly, or you can find me on Twitter where I'll do my best to help.

Project files

The project files for Hacking with Swift are all available on GitHub, where you can view them, fork them, or download them: click here for the GitHub repo.