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)

Using disclosure groups to hide and show content

DisclosureGroup is a view that's used to show or hide content based on the state of a disclosure control. It takes two parameters: a label to identify its content and a binding that controls whether the content is visible or hidden. Let's take a closer look at how it works by creating an app that shows and hides content in a disclosure group.

Getting ready

Create a new SwiftUI project and name it DisclosureGroups.

How to do it…

We will create an app that uses the DisclosureGroup view to view some planets in our solar system, continents on Earth, and some surprise text. The steps are as follows:

  1. Below the ContentView struct, add a state property called showplanets:
    struct ContentView: View {
      @State private var showplanets = true
      // the rest of the content here
    }
  2. Replace the Text view in the body struct with a VStack and a DisclosureGroup view that contains two Text views...