Articles, podcasts and news about Swift development, by John Sundell.
Swift by Sundell is frequently updated with new articles, podcast episodes, videos, and more.
Subscribe via RSS to get notified when new content gets published.
How the share operator enables a Combine publisher to be reused without requiring duplicate work to be performed for each subscriber.
Discover Swift’s Codable protocol, how to fully leverage its compiler synthesis features, and how to use its surrounding APIs to write efficient serialization code.
How Codable’s auto-synthesis works for enums, and how that part of the system has been upgraded in Swift 5.5 to support associated values.
Thanks a lot to Paste for sponsoring Swift by Sundell.
How Swift 5.5 enables us to conditionally compile postfix member expressions using compiler directives, and what kinds of situations that this new feature could be useful in.
Roxana Jula joins John to discuss Apple’s various tools, frameworks, and APIs for building Augmented Reality experiences. How to get started building AR-based apps, what’s the current state of AR on Apple’s platforms, and how might that change if Apple were to introduce dedicated AR hardware in the future?
How Swift’s AsyncSequence and AsyncStream APIs can be used to build asynchronous sequences, and how they relate to Apple’s Combine framework.
Antoine van der Lee, creator of SwiftLee, joins John to discuss the new language features that are being introduced as part of Swift 5.5 — from the brand new concurrency system, to convenience features and various improvements.
How we can now use Swift’s very convenient “dot syntax” to refer to protocol-conforming types, and how that improves some of SwiftUI’s styling APIs.
Various techniques that let us define fully dynamic colors that adapt to the user’s selected color scheme, using either SwiftUI or UIKit.
What Swift’s @unknown attribute does, and why the compiler tells us to use it when switching on certain enums.
Jordan Morgan returns to the show to discuss some of the key new APIs and frameworks that were announced at WWDC21, and how they can be integrated into the apps that we build, now that about two months have passed since the conference took place.
How Swift 5.5 enables computed properties to become either throwing or asynchronous, and what sort of situations that these new capabilities could become useful in.
New in Swift 5.5: Property wrappers can now be applied directly to function arguments, just like how they can be used to add additional functionality to a property or local variable.
Malin Sundberg joins John to talk about her experiences of using SwiftUI to build and ship the time-tracking and invoicing app Orbit on most of Apple’s platforms, and what sort of things that can be good to keep in mind when using SwiftUI in a cross-platform context.
How to compose multiple SwiftUI views to render a shape that’s both stroked and filled at the same time.
What sort of capabilities that a mutating Swift context has, and what the mutating and nonmutating keywords do.
Thanks a lot to ViRE for sponsoring Swift by Sundell.
Chris Lattner returns to the show to discuss Swift’s new concurrency features, the ongoing evolution of the language, and the importance of both language and API design. This, and much more, on this special 100th episode of the show.
Three different ways to dismiss a SwiftUI view that was presented from another view, including a new API that’s being introduced in iOS 15.
Various ways of conditionally creating SwiftUI views that depend on optional values.
Let’s explore how we can make it possible to call async/await-powered APIs within a Combine pipeline.
A look at how SwiftUI’s new refreshable modifier can be used to either add pull-to-refresh to a list, or to build completely custom reloading UIs and logic.
Availability checks let us conditionally use new system APIs and features while still enabling the rest of our code to keep running on older system versions. Let’s take a look at how they can be used.
Various ways to handle mismatches between how an external type is expected to be coded and the data format that an app is using.
Let’s explore a few ways to “bridge the gap” between the new world of async/await and other kinds of asynchronous Swift code.
Setting up two-way bindings between the elements in a collection and a series of SwiftUI views.
How the Swift compiler is now able to automatically perform conversions between Double and CGFloat values.
How the MainActor attribute eliminates the need for us to manually dispatch UI updates on the main queue when using Swift 5.5’s new concurrency system.
Doug Gregor from Apple joins John to discuss Swift 5.5’s new concurrency features in great detail. How do features like async/await and actors work under the hood, and how were those concepts adapted in order to feel right at home within Swift’s existing ecosystem? That, and much more, on this WWDC21 special episode of the show.
Head over to WWDC by Sundell & Friends to find highly technical coverage of WWDC21 and first looks at some of the key new APIs, tools, and frameworks.
With the start of WWDC21 just around the corner, I’d like to share some of my biggest hopes and dreams for this year’s edition of the conference.
Sean Allen returns to the show to talk about using the MVVM design pattern within SwiftUI-based apps, building a course around MapKit and CloudKit, how to approach all of the new material that WWDC has to offer, and what goes into making a really great developer portfolio.
Swift’s enums are awesome, but they’re not always the best choice for modeling a given piece of data. Let’s explore why that is, and what other tools that can be good to keep in mind in order to avoid certain problematic enum cases.
Ish ShaBazz returns to the show for a special pre-WWDC episode about what new APIs and developer tools that Apple might announce at this year’s edition of the conference. What’s in store for Swift and SwiftPM, how might UIKit and SwiftUI continue to evolve, and will this be the year when we’ll finally see Apple’s new AR/VR platform?
When using multiple computed properties within SwiftUI views could become problematic, and various approaches to fix those kinds of problems.
Great options for when we don’t want to create a whole new Xcode project just to try out a quick UI idea.
Thanks a lot to Essential Developer for sponsoring Swift by Sundell.
It’s now possible to create a local variable that’s assigned to an expression that has the same name, without having to manually disambiguate with ‘self’.
A huge update to my suite of Swift static site generation tools, which adds a new API for building HTML components in a very SwiftUI-like way.