Using the Basic SwiftUI Views and Controls

SwiftUI was launched during Apple’s Worldwide Developer Conference (WWDC) in June 2019. Since then, its popularity has kept increasing as it has been adopted widely by the Apple developer community. Apple also releases updates every year, adding new and exciting capabilities to SwiftUI.

SwiftUI is a UI framework that ditches UIKit concepts such as Auto Layout for an easier-to-use declarative programming model. SwiftUI is Apple’s preferred way to build user interfaces. It is a platform-agnostic framework that allows the fast and easy creation of applications that work across Apple platforms (iOS, iPadOS, macOS, WatchOS, and tvOS).

There is no question today about the need to learn about SwiftUI. Apple released the fifth iteration of the framework in 2023 and it is adding more features every year. Here are some other compelling reasons to be proficient in SwiftUI:

• SwiftUI apps can work alongside UIKit apps: You can slowly convert your app’s user interface (UI) to SwiftUI, one screen at a time.
• Industry adoption: SwiftUI has already been adopted by the industry as it was released four years ago. Just looking at job postings for iOS developers, you’ll find out that most of them require experience with SwiftUI. Learning about SwiftUI is a must for current iOS development jobs. In a few more years, SwiftUI will dominate the app development for all the Apple platforms, the same way that Swift took over from Objective-C a few years ago.
• Low learning curve: SwiftUI offers a low learning curve for people who have used declarative programming before. It is also a great way to start learning declarative programming for those with little to no experience.
• Live previews increase speed: SwiftUI live previews provide an instant preview of your UI without having to recompile the whole app. You can quickly prototype apps and make any changes required by your users. This greatly improves the speed of UI development.

This book is designed to be your SwiftUI reference material. Each project focuses on a single concept so that you can understand each concept thoroughly, and then combine multiple concepts to build amazing applications.

In this chapter, we will learn about views and controls, SwiftUI’s visual building blocks for app user interfaces. The following recipes will be covered:

• Laying out components
• Dealing with text
• Using images
• Adding buttons and navigating with them
• Beyond buttons: using advanced pickers
• Applying groups of styles using ViewModifier
• Separating presentation from content with ViewBuilder
• Simple graphics using San Francisco Symbols (SF symbol)
• Integrating UIKit into SwiftUI—the best of both worlds
• Adding SwiftUI to a legacy UIKit app
• Exploring more views and controls