Modern Concurrency: Getting Started

Learn how to use Swift’s new native model for writing safe, efficient concurrent code. Create safe, performant and predictable asynchronous apps using these Swift concurrency features: async/await Tasks MainActor Asynchronous sequences By Audrey Tam.

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Learning path

This is part of the Concurrency in iOS learning path. View path.

Who is this for?

This course is for intermediate Swift developers who are familiar with writing asynchronous applications, but want to leverage the new concurrency features in Swift 5.5 to write safer and more predictable asynchronous apps.

Covered concepts

  • Using async/await
  • Tasks
  • MainActor
  • Asynchronous Sequences

Part 1: Asynchronous Code

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What is Swift concurrency? Why is it better than GCD? What about Combine? In this course, you’ll learn how to create safe, performant and predictable asynchronous apps using these Swift concurrency features: async/await, Tasks, asynchronous sequences and MainActor.

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Explore Task and async/await in a playground.

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Learn how to set up the course server, then use async/await and the task view modifier in the LittleJohn app’s SymbolListView.

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Learn how to define async properties and subscripts and how to iterate over built-in and custom async sequences.

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Use AsyncSequence in the LittleJohn app’s TickerView.

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Learn how to handle the server becoming unavailable during a price update.

Conclusion 1:22
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Review what you learned in Part 1 and see what’s coming up in Part 2.

Part 2: Asynchronous Sequences

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Learn about the app you’ll build in this part of the course and the Swift concurrency tools you’ll use.

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Challenge: Reinforce what you learned in Part 1 by implementing the list view in the SuperStorage app. Try not to peek at LittleJohn’s SymbolListView.

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Use async let to download server status concurrently with the files list.

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In a Button action, call an asynchronous method that updates view properties. Use Task to call the asynchronous method and move the model’s helper methods to MainActor.

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Challenge: Show/hide a progress view spinner.

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Display a progress view while downloading a file in chunks.

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Implement your own custom logic to cancel download tasks that you don’t need anymore.

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Create an AsyncSequence from the Combine publisher of Timer.

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Challenge: Download the file chunks in parallel.

Conclusion 2:19
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Review what you learned in this course and see what’s covered in Modern Concurrency: Beyond the Basics.

Up next

iOS & Swift
Modern Concurrency: Beyond the Basics
Build on your knowledge of async/await, tasks and asynchronous sequences to use concurrent tasks in safe, ... more



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