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)

Converting a completion block function to async await

It's clear that async await is the way that Apple wants us to develop concurrent code in Swift. But what if a framework we have to use (or even our legacy code) still has a completion block-based interface? Swift 5.5 provides a simple way to convert these APIs to async await functions.

In this recipe, we'll use an old framework where one of its functions has a completion block API. We'll convert it to an async await function and we'll use it in a SwiftUI view.

The package we will use is called Lorikeet, implemented by Þorvaldur Rúnarsson (https://github.com/valdirunars). Lorikeet is an aesthetic color scheme generator. Starting with one color, it generates a series of other colors that can be used for creating a color theme for an app.

Getting ready

Create an iOS 15 SwiftUI app called PaletteGenerator.

Import the SPM package from the following address-

Figure 11...