Swift's Advanced Performance Feature: Async

A portrait painting style image of a pirate holding an iPhone.

by The Captain

on
April 14, 2023

Swift's Advanced Performance Feature: Async

Asynchronous programming is mandatory for developing high-performance iOS apps. It's a programming methodology that enables you to perform tasks without interrupting the main application flow. The async/await feature is Swift's advanced performance feature that makes coding asynchrony a lot easier.

How to Use Async in Swift Code

The async/await feature came into existence with the release of Swift 5.5. With this feature, developers can use the async keyword before any task to delay the operation and perform other tasks while the operation runs in the background. Here is an example:

func fetchUserData() async -> [String: Any] {
    let url = URL(string: "https://jsonplaceholder.typicode.com/todos")
    let request = URLRequest(url: url!)
    let (data, _) = try! await URLSession.shared.data(for: request)
    return try! JSONSerialization.jsonObject(with: data) as! [String: Any]
}

The above code block shows an example that fetches user data from the JSONPlaceholder API. The function is declared with the async keyword, indicating that the function should run asynchronously.

What are the Benefits of Async in Swift?

Here are some of the benefits of using async in Swift:

  • Allows you to perform long-running network calls or other time-consuming tasks without blocking the main application flow.
  • Improves the overall responsiveness of the application by keeping the user interface responsive while complex operations continue to run.
  • Reduces the amount of time spent implementing and debugging complex callback patterns.

Conclusion

The async/await feature has made asynchronous programming in Swift much easier compared to the previous method of using callbacks. By using the async keyword before tasks, you can create high-performance applications with responsive user interfaces.