Book Image

iOS 13 Programming for Beginners - Fourth Edition

By : Ahmad Sahar, Craig Clayton
Book Image

iOS 13 Programming for Beginners - Fourth Edition

By: Ahmad Sahar, Craig Clayton

Overview of this book

iOS 13 comes with features ranging from Dark Mode and Catalyst through to SwiftUI and Sign In with Apple. If you're a beginner and are looking to experiment and work with these features to create your own apps, then this updated fourth edition gets you off to a strong start. The book offers a comprehensive introduction for programmers who are new to iOS, covering the entire process of learning the Swift language, writing your own apps, and publishing them on the App Store. This edition is updated and revised to cover the new iOS 13 features along with Xcode 11 and Swift 5. The book starts with an introduction to the Swift programming language, and how to accomplish common programming tasks with it. You'll then start building the user interface (UI) of a complete real-world app, using the latest version of Xcode, and also implement the code for views, view controllers, data managers, and other aspects of mobile apps. The book will then help you apply the latest iOS 13 features to existing apps, along with introducing you to SwiftUI, a new way to design UIs. Finally, the book will take you through setting up testers for your app, and what you need to do to publish your app on the App Store. By the end of this book, you'll be well versed with how to write and publish apps, and will be able to apply the skills you've gained to enhance your apps.
Table of Contents (33 chapters)
1
Section 1: Swift
10
Section 2: Design
15
Section 3: Code
26
Section 4: Features

Understanding arrays

Let's say you want to store the following:

  • List of items to buy at the supermarket
  • Chores that you have to do every month

You would use an array for this.

An array stores values in an ordered list. Here's what it looks like:

Index Value
0 value1
1 value2
2 value3

Values must be of the same type. You can access any value in an array by using the array index, which starts with 0.

If you create an array using the let keyword, its contents can't be changed after it has been created. If you want to change the contents after creation, use the var keyword.

Let's look at how to work with arrays. You'll start by creating an array.

Creating an array

You can create an array...