Book Image

iOS 15 Programming for Beginners - Sixth Edition

By : Ahmad Sahar, Craig Clayton
5 (1)
Book Image

iOS 15 Programming for Beginners - Sixth Edition

5 (1)
By: Ahmad Sahar, Craig Clayton

Overview of this book

With almost 2 million apps on the App Store, iOS mobile apps continue to be incredibly popular. Anyone can reach millions of customers around the world by publishing their apps on the App Store. iOS 15 Programming for Beginners is a comprehensive introduction for those who are new to iOS. It covers the entire process of learning the Swift language, writing your own app, and publishing it on the App Store. Complete with hands-on tutorials, projects, and self-assessment questions, this easy-to-follow guide will help you get well-versed with the Swift language to build your apps and introduce exciting new technologies that you can incorporate into your apps. You'll learn how to publish iOS apps and work with Mac Catalyst, SharePlay, SwiftUI, Swift concurrency, and much more. By the end of this iOS development book, you'll have the knowledge and skills to write and publish interesting apps, and more importantly, to use the online resources available to enhance your app development journey.
Table of Contents (32 chapters)
1
Part 1: Swift
10
Part 2: Design
15
Part 3: Code
25
Part 4: Features

Understanding arrays

Let's say you want to store the following:

  • List of items to buy at a convenience store
  • Chores that you have to do every month

Arrays would be suitable for this. An array stores values in an ordered list. Here's what it looks like:

Figure 5.1: Array

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 an array's contents after creation, use the var keyword.

Let's see how to work with arrays. You'll create an array by assigning a value to it in the next section.

Creating an array

In previous chapters, you created a constant or variable by declaring it and assigning an initial value to it. You can create an array the same way.

Imagine that your spouse has asked you to get some items from a convenience...