Not only Swift

Join me for a special livestream event on June 5th with special guest Cihat Gündüz, creator of ErrorKit! I’ve covered ErrorKit in issue 80 of my newsletter - it provides a developer-friendly API that expands on the existing LocalizedError protocol, and it also comes with a bunch of presets for common error types - very convenient!

Don’t miss this opportunity to learn directly from one of the iOS community’s most innovative developers!

What we’ll cover:

• How / why did you create ErrorKit?
• Which problem does it solve?
• Why is this a problem in the first place?
• Is it plug and play, or do people have to configure it / add their own custom error message?
• How can people contribute?

Tune in on June 5th at 20:00 CET!

This is a fun and engaging talk about Swift’s unexpected behaviors.

For example, 0.1 + 0.2 should be 0.3, but according to Swift, it’s not:

let first = 0.1
let second = 0.2
 
print(first + first == 0.2) // true
print(second + second == 0.4) // true
print(first + second == 0.3) // false

I like how Sophie not only explains these behaviors but also helps us understand their underlying causes. So next time you encounter a weird Swift behavior, you’ll have a better chance of figuring out what’s going on.

Whether or not you should use MVVM with SwiftUI is a hotly debated topic. In this article, Thomas makes the case for NOT using MVVM with SwiftUI, and instead embrace views as the single source of truth.

He claims that SwiftUI was designed with a fundamentally different philosophy than UIKit, and that we don’t need ViewModels to build clean, maintainable apps. In fact, he argues that each view model means more complexity to maintain, more objects to keep in sync, more indirection between intent and action, and ultimately more cognitive overhead for your team.

Goodbye MVVM 🚮

Long live The View 👑

View identity is a fundamental concept in SwiftUI. Understanding it helps you build robust and efficient apps. In this short video, Natalia explains the difference between view identity and view state, and under which circumstances a view’s identity changes - and what that means for it’s associated state.

SwiftUI doesn’t preserve the identity of views by storing or re-using the actual struct instances. Instead it tracks identity through internal bookkeeping often using things like the position in the hierarchy view type and any explicitly provided identifiers.

She then goes on to demonstrate two strategies to preserve view identity - using the view’s opacity and hoisting state to the container view.

This visual library is an excellent resource for SwiftUI developers of all levels. It provides a comprehensive collection of SwiftUI components and modifiers, each accompanied by visual examples and ready-to-use code samples. The site is particularly valuable for discovering new components and understanding how to implement them effectively in your apps. Florian designed the code samples for easy copy-pasting, which is super convenient for rapidly building UIs for your apps.

Firebase AI Logic allows you to call Gemini and Imagen APIs securely from your mobile and web apps. One of they key points is that you don’t need to include your API keys in your app.

Firebase AI Logic is part of the Firebase SDK, and as you can tell from the documentation, it’s a very comprehensive offering.

Francesco managed to put together a compact step-by-step guide on how to get started with Firebase AI Logic in your iOS app, including adding App Check (which ensures only your genuine app can use the API).

Well done, and definitley a must-read.