Head First Swift

Cover
Head First Swift
Copyright
Authors of Head First Swift
Table of contents
How to use this book
	Who is this book for?
	We know what you’re thinking
	We know what your brain is thinking
	Metacognition: thinking about thinking
	Here’s what WE did
	Here’s what YOU can do to bend your brain into submission
	Read me
	The technical review team
	Acknowledgments
1. Introducing swift
	Swift is a language for everything
	The swift evolution of Swift
	Swift into the future
	How you’re going to write Swift
	The path you’ll be taking
	Getting Playgrounds
	Creating a Playground
	Using a Playground to code Swift
	Basic building blocks
	A Swift example
	Congrats on your first steps with Swift!
2. Swift by name
	Building from the blocks
	Basic operators
	Operating swiftly with mathematics
	Expressing yourself
	Names and types: peas in a pod
	Not all data is numbers
	Stringing things along with types
	String interpolation
3. Collecting and controlling
	Sorting pizzas
	Swift collection types
	Collecting values in an array
	How big is that array, exactly? Is it empty?
	Collecting values in a set
	Collecting values in a dictionary
	Tuples
	Everyone needs a good alias
	Control flow statements
	if statements
	switch statements
	Building a switch statement
	Range operators
	More complex switch statements
	Getting repetitive with loops
	Building a for loop
	Building a while loop
	Building a repeat-while loop
	Solving the pizza-sorting problem
	Phew, that’s a lot of Swift!
4. Functions and enums
	Functions in Swift let you reuse code
	Built-in functions
	What can we learn from built-in functions?
	Improving the situation with a function
	Writing the body of the function
	Using functions
	Functions deal in values
	Many happy returns (from your functions)
	A variable number of parameters
	What can you pass to a function?
	Every function has a type
	Function types as parameter types
	Multiple return types
	Functions don’t have to stand alone
	Switching with enums
5. Closures
	Meet the humble closure
	Closures are better with parameters
	Boiling it all down to something useful
	Reducing with closures
	Capturing values from the enclosing scope
	Escaping closures: the contrived example
	Autoclosures provide flexibility
	Shorthand argument names
6. Structures, properties, and methods
	Let’s make a pizza, in all its glory...
	The initializer behaves just like a function
	Static properties make structures more flexible
	Methods inside structures
	Changing properties using methods
	Computed properties
	Getters and setters for computed properties
	Implementing a setter
	Swift Strings are actually structs
	The case for lazy properties
	Using lazy properties
7. Classes, actors, and inheritance
	A struct by any other name (that name: a class)
	Inheritance and classes
	Overriding methods
	Final classes
	Automatic reference counting
	Mutability
8. Protocols and extensions
	The Robot Factory
	Protocol inheritance
	Mutating methods
	Protocol types and collections
	Computed properties in extensions
	Extending a protocol
	Useful protocols and you
	Conforming to Swift’s protocols
9. Optionals, unwrapping, generics, and more
	Dealing with something that’s missing
	Why you might need an optional
	Optionals and handling missing data
	Unwrapping optionals
	Unwrapping optionals with guard
	Force unwrapping
	Generics
	A queue with generics
	Here’s our new Queue type
10. Getting started with SwiftUI
	What’s a UI framework, anyway?
	Your first SwiftUI UI
	UI building blocks
	Making a list, checking it…quite a few times, to get it perfect
	User interfaces with state
	Buttons are for pressing
	Let’s see how far you’ve come
	Create a new SwiftUI Xcode project, for iOS
	Your Xcode will look something like this
	Create a new type to store a todo item in
	Make sure each todo item can be uniquely identified
	Create a user interface for the app
	Implement a way to save the list of todos
	So, that’s a UI framework?
11. Putting swiftUI into practice
	What fancy things can be done with a UI framework?
	Create a new SwiftUI Xcode project, for iOS
	The Executive Timer UI and features
	Creating the basic elements of the app
	Pieces of the UI
	Setting up the UI of the Executive Timer
	Coding the pieces of the UI
	Combining the three elements
	The finishing touches
	Tabbed views for a clean UI
	Build a TabView containing your views
	Creating a new tabbed ContentView
	Creating the tabs and the TabView
	Running your new tabbed Executive Timer
12. Apps, web, and beyond
	A journey must end...
	A recipe for a welcome screen
	Step by step assembly of the welcome screen
	Share the state
	It’s time for our old friend...
	Building an app with multiple views that share state
	Building a two-view score tracker
	The ObservableObject
	The first view
	The second view
	The first view, again
	A fancy AsyncImage
	Meet Vapor, the Swift web framework
	Sending data over the web with Vapor
Index