When switching on an enum, we are required to either explicitly handle all of its cases, or provide a default case that’ll act as a fallback for cases that weren’t matched by any previous case statement. For example like this: struct Article { enum State { case draft case published case removed } var state:…
At WWDC21, Apple introduced a new SwiftUI API that enables us to attach refresh actions to any view, which in turn now gives us native support for the very popular pull-to-refresh mechanism. Let’s take a look at how this new API works, and how it also enables us to build completely custom refreshing logic as…
When starting to adopt Swift’s new async/await feature, we’re likely going to have to find ways to connect and bridge that pattern to any existing asynchronous code that we’ve already written within a given project. Earlier this week, we took a look at how that can be done when it comes to completion handler-based APIs,…
When building iOS and Mac apps, it’s very common to want to present certain views either modally, or by pushing them onto the current navigation stack. For example, here we’re presenting a MessageDetailView as a modal, using SwiftUI’s built-in sheet modifier in combination with a local @State property that keeps track of whether the detail…
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. Sponsor Bitrise: Rock-solid continuous integration for your Swift project, which now offers 50% faster builds and…
Thanks a lot to the team behind the visual regular expressions editor ViRE for sponsoring Swift by Sundell over the past two weeks, enabling me to keep delivering a continuous stream of Swift articles completely for free. I’ll be honest, I’ve never been a huge fan of working with regular expressions as raw strings. I…
One of the ways in which Swift helps us write more robust code is through its concept of value types, which limit the way that state can be shared across API boundaries. That’s because, when using value types, all mutations are (by default) only performed to local copies of the values that we’re working with,…
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…
One challenge when it comes to concurrency on Apple’s platforms is that an app’s UI can, for the most part, only be updated on the main thread. So, whenever we’re performing any kind of work on a background thread (either directly or indirectly), then we always have to make sure to jump back to the…
New in Swift 5.5: The compiler can now automatically perform conversions between Double and CGFloat values. Although the two have always been equivalent on 64-bit systems, before Swift 5.5 (which is currently in beta as part of Xcode 13), we had to manually convert between them in order to satisfy Swift’s type system — since…