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SwiftLee Weekly by Antoine van der Lee

SwiftLee Weekly - Issue 262

Published 3 months ago • 5 min read

This week's SwiftLee Weekly covers:

  • Rendering Pixel Art in SwiftUI
  • .animation() vs. withAnimation()
  • An @Observable performance risk

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST

​Picker in SwiftUI explained with code examples​

While AI greatly helps us, I always look for a quick visual overview of different SwiftUI element styles. This is why I'm writing about pickers in SwiftUI this week: to give a visual overview of the different available styles that I can revisit myself.

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CURATED FROM THE COMMUNITY

​Rendering Pixel Art with SwiftUI​

I didn’t know the interpolation modifier yet! While this is an edge case, it’s good for you to understand how to render tiny bitmaps.
​twocentstudios.com​

​.animation() vs withAnimation(): what's the difference?​

Without reading this article by Vincent Pradeilles: do you know the difference? If not, it’s time to give it a read!
​swiftwithvincent.com​

​Creating App Intents using Assistant Schemas​

App Intents are at the core of many iOS integrations. I even wrote about App Intent-driven development as I believe it can help you build apps faster. This article dives into assistant schemes.
​createwithswift.com​

​Lazy Initialization @State in SwiftUI - Overcoming Premature Object Creation​

Did you know the Observation framework isn’t always resulting in enhanced SwiftUI performance? The case described in this article Fatbobman is an important one to be aware of when using @Observable.
​fatbobman.com​

​Synchronous Work​

Swift Concurrency and suspension points: the moment you think you understand them, a new scenario appears. There are several proposals related to this article (and properly mentioned accordingly!), so things might change soon. Yet, this is a very educational article to help you better understand concurrency.
​massicotte.org​

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Joining the giveaway is free—the winner will be announced in SwiftLee Weekly 264 (March 25th).

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SWIFT EVOLUTION

An overview of last week's Swift Proposal state changes. Check them out when they're in review, as it's your opportunity to influence the direction of Swift's future.

CODE SNIPPET OF THE WEEK

Toggling Booleans

You can find this post on Twitter/X, LinkedIn, or Bluesky.

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Antoine v.d. SwiftLee 
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@twannl
3:44 PM • Mar 10, 2025
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​

QUESTION OF THE WEEK

“
How would you explain async/await?

I'm probably in my concurrency bubble, but interest in this topic seems to be growing lately. Several new Swift Proposals aim for an easier concurrency approach (more on that next week) that feeds social media discussions.

The async/await syntax is part of the concurrency fundamentals and while working on my slides for AppDevCon, I reached out on socials to ask how you would explain this concept.

I asked ChatGPT for one-sentence metaphors:

  • Elevator Ride – You press the button (async), check your phone (await), and step in when the elevator arrives.
  • Coffee Machine – You press the button (async), do other tasks (await), and come back when the coffee is ready.

But I also received a few great ones on social media:

  • An asynchronous method needs to be awaited for its result
  • You have a team. Ask someone to do something. He will get back to you when the work is done. In the meantime, you're free to do something unrelated.

Everyone will have their favorite, and despite the many challenges concurrency brings, I'm convinced we'll get to a state in Swift where writing asynchronous code will be easier than we're used to with custom locking mechanisms and GCD-closure-based solutions. Make sure to check the proposal updates in this newsletter since exciting changes are coming. I'm personally monitoring them closely and look forward to writing a dedicated article to tell you all about it!

I'm open to new questions!​
Ask your question via this form (anonymously) or reply to this email with your question.

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Thank you so much for your support, and until next Tuesday,

Antoine

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SwiftLee Weekly by Antoine van der Lee

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