Wei-Meng Lee - SwiftUI For Dummies

SwiftUIFor Dummies Published by: John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030-5774, www.wiley.com Copyright 2020 by John Wiley & Sons, Inc., Hoboken, New Jersey Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except as permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without the prior written permission of the Publisher. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http://www.wiley.com/go/permissions . Trademarks: Wiley, For Dummies, the Dummies Man logo, Dummies.com, Making Everything Easier, and related trade dress are trademarks or registered trademarks of John Wiley & Sons, Inc. and may not be used without written permission. SwiftUI is a trademark of Apple, Inc. All other trademarks are the property of their respective owners.

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1. Chapter 1
2. Chapter 3
3. Chapter 4
4. Chapter 5
5. Chapter 6
6. Chapter 7
7. Chapter 8
8. Chapter 9
9. Chapter 10
10. Chapter 11
11. Chapter 12
12. Chapter 13

In 2019, at the Apple Worldwide Developers Conference, Apple announced SwiftUI, a declarative programming framework for developing user interfaces (UIs) for iOS and macOS applications.

With SwiftUI, Apple aims to modernize the iOS development experience. Theres no doubt that SwiftUI makes it much easier and more efficient for developers to create apps, but it also means you have to learn something new. Thats where SwiftUI For Dummies comes in. This book provides you with all the essentials that you need to learn to become a successful iOS developer using SwiftUI.

This book covers the basics of SwiftUI. Because SwiftUI supports iOS, iPadOS, macOS, watchOS, and tvOS, its a really big topic.

To narrow the scope, this book focuses on using SwiftUI with iOS, specifically to program iPhone apps. In this code-intensive book, youre encouraged to try out the examples in each chapter. The chapters are designed to be compact, easy to follow, and easy to understand. However, you dont have to read this book from the first page to the last. Each chapter is designed to be independent, and youre free to start with any chapter to find the topic that youre interested in. I dont use many special conventions, but here are a couple points you should be aware of: Sidebars (text in gray boxes) and anything marked with the Technical Stuff icon are skippable, and code appears in monofont .

Pretty simple, right? Finally, within this book, you may note that some web addresses break across two lines of text. If you're reading this book in print and want to visit one of these web pages, simply key in the web address exactly as its noted in the text, pretending as though the line break doesnt exist. If youre reading this as an e-book, youve got it easy just click the web address to be taken directly to the web page.

This book is for people who are new (or relatively new) to using SwiftUI for iOS development. Though I do not assume that youre familiar with iOS programming, I do assume the following:

• Youre familiar with the basics of programming.
• Youre familiar with how an iPhone works.
• You have a Mac that you can use to try out the examples in this book.
• You dont need an iPhone to test the applications in this book (except for where I show you how to load your iPhone with the application youve built); the iPhone Simulator will suffice.

Some chapters in this book assume that youre familiar with UIKit programming (the framework used for iOS programming prior to SwiftUI). Like other books in the For Dummies series, this book uses icons, or little pictures in the margins, to draw your attention to certain kinds of material. Like other books in the For Dummies series, this book uses icons, or little pictures in the margins, to draw your attention to certain kinds of material.

Here are the icons that I use: Whenever I tell you something useful or important enough that youd do well to store the information somewhere safe in your memory for later recall, I flag it with the Remember icon. The Technical Stuff icon marks text that contains some for-nerds-only technical details or explanations that youre free to skip.

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