Hello Swift! you own this product

iOS app programming for kids and other beginners

Tanmay Bakshi

April 2019
ISBN 9781617292620
400 pages

Included with a Manning Online subscription

printed in black & white

available in Korean

catalog / Programming Languages and Styles / Mobile App Development / Mobile Development

table of content

1 Get ready to build apps with Swift!

1.1 Your “I can do it!” journey begins

1.1.1 What is an app, anyway?

1.1.2 The pieces of a good app

1.1.3 What is programming?

1.1.4 From idea to app

1.2 What is Swift?

1.2.1 What’s so special about Swift?

1.2.2 Swift can’t do everything

1.3 Prepping your app toolbox

1.3.1 Gather hardware

1.3.2 Install Xcode

1.3.3 Setup Optional Developer Account

1.3.4 Start XCode for the first time

1.4 Write code and see it work in the Swift Playground

1.4.1 What Is the Playground?

1.4.2 Create a Playground

1.4.3 Play with code in the Playground

1.5 Check your app knowledge!

2 Create your first app

2.1 Hello Apps!

2.2 Your first app: Hello World!

2.2.1 What does this app do?

2.2.2 Set up the project

2.2.3 The Xcode interface

2.2.4 Create the UI

2.2.5 Run your app

2.3 Discover the user interface

2.3.1 What is a UI?

2.3.2 Develop an app on your own

2.3.3 Change text colors

2.3.4 Change the background color of a control

2.3.5 Change the background color of a view

2.3.6 More about controls: Try these for a challenge

2.3.7 A few more things you can do with the Attributes inspector

2.3.8 Segues: Using controls to navigate screens

2.3.9 Try an extra challenge

2.4 Designing good UIs

2.5 Try this app on your own

2.6 Test your app knowledge

3 Your first real Swift code using variables

3.1 Apps store data in variables

3.1.1 What is a variable?

3.1.2 Hands on!

3.1.3 How does an app use and save variables?

3.1.4 What types of variables are there?

3.1.5 How to create variables

3.1.6 Hands on!

3.2 Declaring variables and changing values

3.2.1 Declaring variables

3.2.2 Changing variable values

3.2.3 Hands on! Spying on data

3.2.4 Using \ and () to format text

3.3 Transforming your data

3.3.1 Concatenating data

3.3.2 Hands on!

3.3.3 Test these rules

3.3.4 Converting data

3.4 Math Operation Theater

3.4.1 What is an Operation?

3.4.2 Do basic Math with Swift (+, -, *, /)

3.4.3 So I can only do math in a print() function?

3.4.4 Step up in math with Swift (square root, power, modulus)

3.4.5 Hands on!

3.4.6 Advanced math in the playground

3.5 Check your app knowledge

4 I/O laboratory

4.1 How apps and users interact

4.2 How do users get output?

4.2.1 Start with Hello World

4.2.2 Add a variable to hold the label

4.2.3 Connect your label variable to a label on the view

4.2.4 The Interface Builder

4.3 Users give apps input

4.3.1 Add a text field and button to the app

4.3.2 Add code to connect the text field to code

4.3.3 Add the function to change the label text to input text

4.4 Check your app knowledge

4.5 App-Activity: Concatenate

4.5.1 What does this app do?

4.5.2 Create the UI

4.5.3 Code the app

4.6 App-Exercise: Greeting Generator

4.6.1 What does this app do?

4.6.2 Create the UI

4.6.3 Code the app

4.6.4 Run the app

5 Computers make decisions, too!

5.1 Conditions with the if statement

5.1.1 if this is true, then do something

5.2 App: Which Number is Bigger?

5.2.1 What does this app do?

5.2.2 Set up the project

5.2.3 Create the UI

5.2.4 Code the app

5.2.5 Connect IBOutlets to Controls and IBActions to Buttons

5.2.6 Learn How the Code Works

5.2.7 Run the App

5.2.8 Run the app again!

5.2.9 Run the code, again!

5.2.10 Recapping the If, Else, and Else If statement

5.3 switch statements

5.4 App: The Mystery of the Entered Number

5.4.1 What does this App do?

5.4.2 Create the UI

5.4.3 Code the app

5.4.4 Run the App

5.5 Check your app knowledge

5.6 App-Exercise: Gold, Silver, Bronze

5.6.1 What does this app do?

5.6.2 Set up the project

5.6.3 Create the UI

5.6.4 Code the app

5.6.5 Run your app

5.7 App-Exercise: tTables the Times Tables Bee!

5.7.1 What does this app do?

5.7.2 Set up the project and create the UI

5.7.3 Code the app

5.7.4 Learn How the Code Works

5.7.5 Run Your App!

6 Let computers do repetitive work

6.1 Controlling repetition

6.2 for-in loop statements

6.2.1 Try it Yourself

6.2.2 How does it work?

6.2.3 Playground Example

6.3 while loop statements

6.3.1 Try it yourself

6.3.2 The Not Equal To (!=) Operator

6.3.3 Playground example

6.3.4 The repeat while loop

6.3.5 Playground Exercise: Repeat While

6.4 APP: How Many Times?

6.4.1 What does this app do?

6.4.2 Set Up the Project and Create the UI

6.4.3 Code the app

6.4.4 Run Your App

6.5 Check your app knowledge

6.6 App-Exercise: Hang your Word Upside-Down!

6.6.1 What does this app do?

6.6.2 Explanation, Playground Exercise and including the helper code

6.6.3 Set Up the Project and Create the UI

6.6.4 Code the app

6.6.5 Run your app

7 Knitting variables into arrays and dictionaries

7.1 Why do we need arrays and dictionaries?

7.2 What is an array?

7.2.1 Arrays start counting with 0!

7.2.2 Getting to your data

7.2.3 Altering the Array

7.2.4 Looping Through Arrays

7.3 10 Number Sorter app

7.3.1 What does this app do?

7.3.2 Set up the project and create the UI

7.3.3 Code the app

7.3.4 Learn how the code works

7.3.5 Run your app

7.4 Go to the second dimension (rows and columns)

7.5 What is a dictionary?

7.5.1 Turning a dictionary into code

7.5.2 Creating a dictionary and getting to your data

7.5.3 Changing the dictionary

7.5.4 Looping through data in dictionaries

7.6 Friend List app

7.6.1 What does this app do?

7.6.2 Set up the app, and create the UI

7.6.3 Code the app

7.7 Check your app knowledge

7.8 App-Exercise: Alphabet Unscrambler

7.8.1 What does this app do?

7.8.2 Set up the project and Create a UI

7.8.3 Code the app

7.8.4 Learn how the code works

7.8.5 Run the app

8 Reuse your code: Clean it with function detergent

8.1 Reuse and clean your code with functions

8.1.1 Simple functions

8.2 Giving info to your reusable code

8.2.1 Try it for yourself.

8.3 Getting info from your reusable code

8.4 Check your app knowledge

8.5 App-Exercise: Virtual Dice

8.5.1 What does this app do?

8.5.2 Set up the project and create the UI

8.5.3 Code the app

8.5.4 Learn how the code works

8.5.5 Run your app

8.6 App-Exercise: Rock Paper Scissors!

8.6.1 What does this app do?

8.6.2 Set up the project and create the UI

8.6.3 Code the app

8.6.4 Connect the IBOutlets and IBActions

8.6.5 Learn how the code works

8.6.6 Run your app

8.7 App-Exercise: Money Denomination

8.7.1 What does this app do?

8.7.2 How does this app work?

8.7.3 Set up the project and create the UI

8.7.4 Codethe App

8.7.5 ConnectIBOutlets and IBActions

8.7.6 Run the app

9 Reduce your code: Use less, do more with class detergent

9.1 Reduce and clean your code with classes

9.1.1 What is a class?

9.1.2 Why you should learn to use classes

9.1.3 Have some fun with classes

9.1.4 How do classes reduce code?

9.2 Create a class

9.2.1 Add a variable

9.2.2 Create Instances of your class

9.2.3 Change the value of a variable

9.2.4 Adding Functionality to Classes

9.2.5 Quick review

9.2.6 Add an initializer that does something every time you create an instance

9.3 Like father, like son: Inheritance!

9.4 All about scope

9.4.1 What is variable’s scope?

9.5 Calculator app

9.5.1 What does this app do?

9.5.2 Create the UI

9.5.3 How does this app work?

9.5.4 Code the app

9.5.5 Connect IBOutlets and IBActions

9.5.6 Run the app

9.6 Check your app knowledge

9.7 App-Exercise: Metric Conversion!

9.7.1 What does this app do?

9.7.2 Math: Negative powers

9.7.3 Creating the UI

9.7.4 Code the app

9.7.5 Connect IBOutlets and IBActions

9.7.6 Run your app

9.8 Extra app-exercise: Metric Conversion app, Part 2

9.8.1 What does this app do?

9.8.2 Code the app

9.8.3 Run the app

10 Reading and Writing Files

10.1 What is in a file?

10.1.1 What is File Content Managing?

10.2 File Content Manager app

10.2.1 What does this app do?

10.2.2 Set up the project and create the UI

10.2.3 Code the app

10.2.4 Learn how the code works

10.2.5 Run your app

10.3 Hangman app

10.3.1 What does this app do?

10.3.2 Setup the project and create the UI

10.3.3 Code the app

10.3.4 Connect the Variables, IBOutlets, and IBActions

10.3.5 Run the app

10.4 Check your app knowledge

10.5 App-Activity: Store your name and birth date

11 Frameworks: Bookshelves of classes

11.1 What is a framework?

11.2 Create a framework

11.2.1 What does this app do?

11.2.2 Create the project

11.2.3 Code the app

11.2.4 Learn how the code works

11.2.5 Build the framework

11.2.6 Use the framework

11.3 App: Load Save, Part 2, using frameworks

11.3.1 What will we do to this app?

11.3.2 Removing the read and write functions

11.3.3 Creating the framework reference in Xcode

11.3.4 Coding the framework in the LoadSave app

11.3.5 Run your app

11.4 Check your app knowledge

12 SpriteKit: Fun animation time

12.1 Meet SpriteKit

12.2 How does SpriteKit work?

12.2.1 Pixels

12.2.2 Coordinate System

12.3 Drag the Square (DTS) app

12.3.1 What does this app do?

12.3.2 Create the project

12.3.3 Code the app

12.3.4 Run the app

12.4 A Christmas Tree app to try on your own

12.5 Check your app knowledge

13 Time to watch your WatchKit code

13.1 Number Guessing Game app

13.1.1 What does this app do?

13.1.2 Create the UI

13.1.3 Coding the application

13.1.4 Run your application

13.2 Check your app knowledge

14 Continuing your journey with Swift

14.1 Resources

14.1.1 liveBook Discussion Forum

14.1.2 Stack Overflow

14.1.3 GitHub

14.1.4 YouTube and Books

14.2 What’s next?

Appendixes: Preface

Appendix A: Check if I am Prime!

A.1 What does this app do?

A.2 Setup the project and create the UI

A.3 Code the app

A.3.1 Create IBOutlets and IBActions

A.4 Run your app

Appendix B: Mean Median Detective

B.1 What does this app do?

B.2 Setup the project and create the UI

B.3 Code the app

B.4 Create the IBOutlets, functions, and IBActions

B.5 Extra challenge

Appendix C: Factoring Factory

C.1 What does this app do?

C.2 Setup the project and create the UI

C.3 Code the app

C.3.1 Create IBOutlets and IBActions

Appendix D: How Big Is a Triangle?

D.1 What does this app do?

D.2 Setup the project and create the UI

D.3 Code the app

D.3.1 Add the IBOutlets and IBAction

D.3.2 Learn how the code works

Appendix E: I’m mixed up, make me improper!

E.1 What does this app do?

E.2 Set up the project and create the UI

E.3 Learn how this code works

E.4 Code the app

E.4.1 Create the IBOutlets, functions, and IBActions

Appendix F: Installation

Overview

1 Get ready to build apps with Swift!

This chapter welcomes brand‑new programmers and sets the stage for a fun, hands‑on journey into building iOS apps with Swift. It introduces the big picture—what apps are, what programming means, and how you’ll quickly move from curiosity to creating your first working code. You also get an overview of the learning path: you’ll gather the right tools, explore Swift through Playgrounds, and build confidence milestone by milestone.

Next, it clarifies what makes an app and what makes a good one—clear visuals, simple and readable design, responsiveness, usefulness, and reliability. You learn the essence of programming as giving step‑by‑step instructions (code) that computers execute precisely, excelling at math and repetitive tasks. The chapter maps the idea‑to‑app cycle: prototype, test, fix bugs, iterate, and submit to the App Store—persevering through feedback until your app is accepted.

Finally, it introduces Swift as Apple’s modern, concise, and readable language, highlights real‑time learning with Playgrounds, and notes that advanced work may occasionally draw on Objective‑C and Apple’s Cocoa frameworks. You prepare your toolbox by using a Mac, installing Xcode, and optionally adding a developer account if you plan to publish. The chapter concludes with a quick win in Xcode’s Playground—running a simple print statement—so you can immediately see Swift in action and get ready to build your first real app next.

Screenshots from my first app on the App store

Think of an idea! Apps for everyone!

Walking with a mobile device and walking with a laptop.

All of these app pieces are necessary!

: The programming process

: The steps to creating an app.

: We’ll mostly work with Swift, but we need a little Objective-C and Cocoa to make our apps better.

MacBook Air and Mac mini are just a couple of options for developing your apps (left); iPad, iPhone and iPod touch are testing options (right)

The default playground.

The playground after you’ve deleted the text.

After you’ve typed your first code, the screen will look like this.

See how the text changed in the sidebar?

Check your app knowledge!

Try these:

What would you type if you want to display: “Good morning Swift” in the playground?
What will be displayed if you type print(“5+4”)?
What will be displayed if you type print(5+4)?
What qualities should your app have to be a good app, Why?

FAQ

What is an app?

An app (short for application) is a program created for a specific purpose—like entertaining, teaching, informing, or solving a problem. Most people use the word “app” to mean software that runs on mobile devices such as iPhones and iPads.

What do you mean by mobile devices?

Mobile devices are portable computers you can use almost anywhere—phones and tablets like iPhone, iPad, and iPod touch. Their portability makes them ideal for using apps on the go, unlike desktop or laptop computers.

What makes a good app?

Appealing, memorable graphics
Simple, uncluttered design
Readable text with clear contrast and comfortable size
Quick, responsive interactions
A useful purpose (entertain, teach, inform, or solve a problem)
Reliability—no bugs and does what it’s supposed to do

What is programming?

Programming is writing step-by-step instructions—called code—that tell a computer exactly what to do. Computers excel at calculations and repetitive tasks, so clear instructions let them handle the hard or boring work for you.

How do I turn an idea into an App Store app?

Start with an idea.
Build a basic version (a starter app).
Test it and list bugs or issues.
Fix problems and polish the design.
Repeat testing and fixing until it’s solid.
Submit to the App Store.
If rejected, apply Apple’s feedback and resubmit.
Persevere—iterate until it’s accepted.

What is Swift and why is it great for beginners?

Swift is Apple’s modern programming language for iOS, macOS, watchOS, and tvOS. It uses clear, English‑like syntax, often requires less code (reducing bugs), is open source, and includes Playgrounds so you can see results instantly as you learn.

Can Swift do everything on its own?

Swift covers a lot, but advanced apps sometimes use a bit of Objective‑C and Apple’s Cocoa frameworks for tasks like audio/video, graphics/animation, data management, and networking. You’ll mostly use Swift, adding small pieces as you advance.

What hardware, software, and accounts do I need?

A Mac running macOS High Sierra (10.13.4) or later with several GB of free space
Xcode (free from the Mac App Store)
Optional: an iPhone/iPad/iPod touch for on‑device testing (otherwise use Xcode’s Simulator)
An Apple ID to download Xcode
Optional: an Apple Developer Program membership ($99/year) to publish on the App Store

How do I install Xcode and create my first Playground?

Install Xcode from the Mac App Store, sign in with your Apple ID, accept the license, and allow any required components (you may need the Mac’s admin password). On first launch, choose “Get started with a Playground,” pick the iOS Blank template, name and save it, and enable Developer Mode if prompted.

What is print() in Swift and why do I need it?

print() is a built‑in Swift function that outputs text so you can see results while you code. For example, print("Hello Swift Apps!") shows the message in the results area. Simply typing the text isn’t enough—you use print() to tell Swift to display it. To close the Playground, press Command+Q (quit Xcode) or Command+W (close the window).

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pdf, ePub, online

$27.99 $18.19

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pro $24.99 per month

access to all Manning books, MEAPs, liveVideos, liveProjects, and audiobooks!
choose one free eBook per month to keep
exclusive 50% discount on all purchases
renews monthly, pause or cancel renewal anytime

lite $19.99 per month

access to all Manning books, including MEAPs!

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