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)

Chapter 4: Viewing while Building with SwiftUI Preview

Developing an application requires several interactions between clients and developers. For example, clients may sometimes request minor changes such as colors, fonts, and image positioning. Previously, developers would need to update their designs in Xcode and recompile all the code before viewing changes. SwiftUI solves this problem by introducing canvas previews. Previews allow for live viewing of UI changes without recompiling code.

In this chapter, we will learn how to make effective use of Xcode previews to speed up the UI development time. This chapter includes the following recipes:

  • Previewing a layout in dark mode
  • Previewing a layout at different dynamic type sizes
  • Previewing a layout in a NavigationView
  • Previewing a layout on different devices
  • Using previews in UIKit
  • Using mock data for previews