Book Image

SwiftUI Cookbook

By : Giordano Scalzo, Edgar Nzokwe
Book Image

SwiftUI Cookbook

By: Giordano Scalzo, Edgar Nzokwe

Overview of this book

SwiftUI is an innovative and simple way to build beautiful user interfaces (UIs) for all Apple platforms, right from iOS and macOS through to watchOS and tvOS, using the Swift programming language. In this recipe-based book, you’ll work with SwiftUI and explore a range of essential techniques and concepts that will help you through the development process. The recipes cover the foundations of SwiftUI as well as the new SwiftUI 2.0 features introduced in iOS 14. Other recipes will help you to make some of the new SwiftUI 2.0 components backward-compatible with iOS 13, such as the Map View or the Sign in with Apple View. The cookbook begins by explaining how to use basic SwiftUI components. Then, you’ll learn the core concepts of UI development such as Views, Controls, Lists, and ScrollViews using practical implementation in Swift. By learning drawings, built-in shapes, and adding animations and transitions, you’ll discover how to add useful features to the SwiftUI. When you’re ready, 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 while 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 found in building SwiftUI apps.
Table of Contents (15 chapters)

Chapter 9: Driving SwiftUI with Combine

In this chapter, we'll learn how to manage the state of SwiftUI Views using Combine. In the Worldwide Developers Conference (WWDC) 2019, Apple not only introduced SwiftUI but also introduced Combine, a perfect companion to SwiftUI for managing the declarative change of state in Swift.

In recent years, given the success of Functional Reactive Programming (FRP) in different sectors of the industry, the same concept has started to be used in the iOS ecosystem, firstly with ReactiveCocoa, the original framework in Objective-C, then in porting ReactiveSwift, and then RxSwift, which is the Swift implementation of ReactiveX, an umbrella of frameworks in different languages that have the same interfaces and functionalities.

In a typical Apple way, Apple took the best practices matured over years of trial and error from the community, and instead of acquiring either ReactiveSwift or RxSwift, Apple decided to reimplement the concepts, simplify...