Book Image

SwiftUI Cookbook - Second Edition

By : Giordano Scalzo, Edgar Nzokwe
Book Image

SwiftUI Cookbook - Second Edition

By: Giordano Scalzo, Edgar Nzokwe

Overview of this book

SwiftUI provides an innovative and simple way to build beautiful user interfaces (UIs) for all Apple platforms, from iOS and macOS through to watchOS and tvOS, using the Swift programming language. In this recipe-based cookbook, you’ll cover the foundations of SwiftUI as well as the new SwiftUI 3 features introduced in iOS 15 and explore a range of essential techniques and concepts that will help you through the development process. The cookbook begins by explaining how to use basic SwiftUI components. Once you’ve learned the core concepts of UI development, such as Views, Controls, Lists, and ScrollViews, using practical implementations in Swift, you'll advance to adding useful features to SwiftUI using drawings, built-in shapes, animations, and transitions. You’ll understand how to integrate SwiftUI with exciting new components in the Apple development ecosystem, such as Combine for managing events and Core Data for managing app data. Finally, you’ll write iOS, macOS, and watchOS apps by sharing the same SwiftUI codebase. By the end of this SwiftUI book, you'll have discovered a range of simple, direct solutions to common problems encountered when building SwiftUI apps.
Table of Contents (17 chapters)

Integrating UIKit into SwiftUI – the best of both worlds

SwiftUI was announced at WWDC 2019 and is only available on devices running iOS 13 and above. Due to its relative immaturity, SwiftUI may lack broad API coverage compared to UIKit. For example, as of July 2021, at the time of this writing, pictures and movies can only be handled using UIKit's UIImagePickerController. There is, therefore, a need to implement certain UIKit APIs in SwiftUI.

In this recipe, we'll look at how to integrate UIKit APIs in SwiftUI. We will create a project that wraps instances of UIActivityIndicatorView to display an indicator in SwiftUI.

Getting ready

Open Xcode and create a SwiftUI project named UIKitToSwiftUI.

How to do it…

We can display UIKit views in SwiftUI by using the UIViewRepresentable protocol. Follow these steps to implement the UIActivityIndicatorView in SwiftUI:

  1. Within the Xcode menu, click File | New | File and select Swift File. Name the...