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)

Showing Core Data objects with @FetchRequest

Probably the most critical feature of persistent storage is its fetching capability. Indeed, we could prebuild a Core Data database and bundle it with our app, which would just read and present the data. An example of this kind of app could be a catalogue for a clothes shop, which contains the clothes for the current season. When the new fashion season arrives, a new app with a new database is created and released.

Given the importance of having this skill, Apple have added a powerful property wrapper to make fetching data from a repository almost trivial. In this recipe, we'll create a simple contact list visualizer in SwiftUI. The objects in the repository will be added the first time we run the app, and ContentView will present the contacts in a list view.

Getting ready

Let's create a SwiftUI app called FetchContactsApp. Ensure that you check the Use Core Data checkbox, as shown in the following screenshot: