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

14.3 Working with Arrays in Swift

Once an array exists, a wide range of methods and properties are provided for working with and manipulating the array content from within Swift code, a subset of which is as follows:

14.3.1 Array Item Count

A count of the items in an array can be obtained by accessing the array’s count property:

var treeArray = ["Pine", "Oak", "Yew"]

var itemCount = treeArray.count

 

print(itemCount)

Whether or not an array is empty can be identified using the array’s Boolean isEmpty property as follows:

var treeArray = ["Pine", "Oak", "Yew"]

 

if treeArray.isEmpty {

    // Array is empty

}

14.3.2 Accessing Array Items

A specific item in an array may be accessed or modified by referencing the item’s position in the array index (where the first item in the array has index position 0) using a technique referred to as...