Book Image

SwiftUI Essentials – iOS 14 Edition

By : Neil Smyth
Book Image

SwiftUI Essentials – iOS 14 Edition

By: Neil Smyth

Overview of this book

Do you want to create iOS apps with SwiftUI, Xcode 12, and Swift 5.3, and want to publish it on the app store? This book helps you achieve these skills with a step-by-step approach. This course first walks you through the steps necessary to set up an iOS development environment together and introduces Swift Playgrounds to learn and experiment with Swift—specifically, the Swift 5.3 programming language. After establishing key concepts of SwiftUI and project architecture, this course provides a guided tour of Xcode in SwiftUI development mode. The book also covers the creation of custom SwiftUI views and explains how these views are combined to create user interface layouts, including the use of stacks, frames, and forms. One of the more important skills you’ll learn is how to integrate SwiftUI views into existing UIKit-based projects and explain the integration of UIKit code into SwiftUI. Finally, the book explains how to package up a completed app and upload it to the app store for publication. Along the way, the topics covered in the book are put into practice through detailed tutorials, the source code for which is also available for download. By the end of this course, you will be able to build your own apps for iOS 14 using SwiftUI and publish it on the app store. The code files for the book can be found here: https://www.ebookfrenzy.com/retail/swiftui-ios14/
Table of Contents (56 chapters)
56
Index

20.6 Modifying Views

It is unlikely that any of the views provided with SwiftUI will appear and behave exactly as required without some form of customization. These changes are made by applying modifiers to the views.

All SwiftUI views have sets of modifiers which can be applied to make appearance and behavior changes. These modifiers take the form of methods that are called on the instance of the view and essentially wrap the original view inside another view which applies the necessary changes. This means that modifiers can be chained together to apply multiple modifications to the same view. The following, for example, changes the font and foreground color of a Text view:

Text("Text 1")

    .font(.headline)

    .foregroundColor(.red)

Similarly, the following example uses modifiers to configure an Image view to be resizable with the aspect ratio set to fit proportionally within the available space:

Image(systemName...