Grand Central Dispatch (GCD) (Udacity)

What you will learn

- Closures Reloaded

Closures in Swift

Properties of closures that we bypassed in our Swift Syntax course

- Grand Central Dispatch

Apple's open source library Grand Central Dispatch

How GCD allows you to send tasks to the background and (equally important) to the foreground

How and what you can send to the background and what must always run in the foreground

- Sample App

Create a simple App that downloads huge images (the easiest way to block the UI)

Send this network lengthy task to the background in 2 different ways

Run closures in the background

Design methods that take a completion closure

Prerequisites and requirements

To be successful in this course, you should be comfortable programming in Swift, and understand closures. You can learn these skills in our Swift Syntax course.

Familiarity with The Hitchhiker's Guide to the Galaxy and The Matrix are also recommended in order to understand the jokes in this course.

Why take this course?

Almsot all Apps consume data from web services, and therefore must use background threads for these lengthy operations.

Even though we provide a black box solution for concurrency in the iOS Networking with Swift course, it is important that you understand how concurrency works in iOS.

This knowledge is vital to deliver Apps that won't be rejected from the App Store and also provide a great user experience.

On top of that, GCD is a frequent topic in iOS job interviews.