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)

Creating a context menu

A context menu is a pop-up menu used to display actions that the developer anticipates the user might want to take. SwiftUI context menus are triggered using 3D Touch on iOS and a right-click on macOS.

A context menu consists of a collection of buttons displayed horizontally in an implicit HStack.

In this recipe, we will create a context menu to change the color of an SF symbol.

Getting ready

Create a new SwiftUI project named ContextMenuApp.

How to do it

We will display a light bulb in our view and change its color using a context menu. To achieve this, we'll need to create an @State variable to hold the current color of the bulb and change its value within the context menu. The steps are as follows:

  1. Just above the body variable in ContentView.swift, add an @State variable to hold the color of the bulb. Initialize it to red:
    @State private var bulbColor =
  2. Within the body variable, change the Text struct to an Image...