Swift 5.3 released!
With the release of Xcode 12 this week, we also got the official release of Swift 5.3. The focus of this release is language refinements, developer experience, and expanding the Swift ecosystem. In this post, Holly Borla from the Swift compiler team at Apple provides an overview of the release.
Posted on September 19, 2020
#swift 5.3
SwiftUI 2.0: The Future is Declarative
In this post, Goran Brias takes a detailed look at the state of SwiftUI - what it promised, what it delivered, and where it's going. Goran's main point here is that SwiftUI is not just an alternative, it is the future of UI development on Apple platforms. A very interesting read.
Posted on September 18, 2020
#swiftui
Testing delegates and protocols in XCTest
The delegate pattern uses composition to provide similar advantages to object inheritance and is a pattern commonly used when developing for Apple's platforms. In this short post, Sarun Wongpatcharapakorn demonstrates his technique for testing code which uses delegation.
Posted on September 17, 2020
#testing
#xctest
Standard library behavior change for LazyMapCollection prefix to act as a Sequence
The Swift standard library provides lazy variations of its Sequence and Collection types, on which operations such as map and filter are implemented lazily. This means that the actual computations will only occur when the results are needed. In this Swift evolution pitch, Greg Titus proposes an addition to the standard library that improves the behavior of the LazyMapCollection type.
Posted on September 16, 2020
#evolution
#collection
#sequence
Porting @AppStorage to iOS 13
The SwiftUI AppStorage property wrapper, available in iOS 14, is a type that reflects a value from UserDefaults and invalidates a view when the value changes. In this post, Xavier Lowmiller builds his version of AppStorage, creating a new type that provides the same functionality and can be used in iOS 13.
Posted on September 15, 2020
#swiftui
Micro-interactions: Async Button
This tutorial from Jean-Marc Boullianne shows us how to create an asynchronous button micro-interaction for an app. This is part of a series of tutorials Jean-Marc has written on micro-interactions, and this particular post is a great example of a simple micro-interaction that adds polish to an app.
Posted on September 14, 2020
#swiftui
#micro-interaction
Support Negative Availability Literals
The availability condition #available is used to execute code conditionally based on the required platform and version conditions. Currently, it's only possible to check if conditions are positively satisfied. In this Swift evolution pitch, Bruno Rocha proposes extending #available to support checking if conditions are not satisfied.
Posted on September 13, 2020
#evolution
Conditional view modifiers
SwiftUI provides a wide range of view modifiers which produce a new version of the original value when applied to a view or another view modifier. It's possible that when working with SwiftUI views, we may want to conditionally apply a view modifier based on certain conditions. In this post, Federico Zanetello shows us how we can use view extensions to handle such cases.
Posted on September 12, 2020
#swiftui
Private APIs, Objective-C runtime, and Swift
Objective-C and Swift can be used together, and it's still very common for apps and projects to contain a mix of both. Calling public Objective-C APIs from Swift involves exposing the APIs via a bridging header. However, calling private, or Swift-unavailable, Objective-C APIs from our Swift code is also possible, thanks to Objective-C's dynamic nature. In this post, Victor Pavlychko focuses on accessing such APIs using the Objective-C runtime.
Posted on September 11, 2020
#objective-c
#dynamic
#runtime
withAnimation completion callback with animatable modifiers
SwiftUI provides excellent support for animations, enabling us to implement simple animations using its withAnimation view modifier. In this post, Antoine Van Der Lee shows us how to create a custom animatable modifier which triggers a completion callback once the animation completes.
Posted on September 10, 2020
#swiftui
#animation