SWIFT2

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operators can be set into 3 categories

1. Unary — operate on single target 2. Binary — operate on 2 targets 3. Ternary — operate on 3 targets

candidates for enums

1. days in week 2. months in year 3. planets in a system 4. categories of products 5. types of vehicles 6. classification of species 7. roles of user

Views are responsible for:

1. handling content on the screen 2. handling user interaction 3. And managing the layout for any subviews in the view

2 methods to check whether an optional holds a value:

1. if let, and != nil var favoriteFood: String? if let food = favoriteFood { print(food) } favoriteFood = "worms" if favoriteFood != nil { print(favoriteFood!) }

Nil coalescing operater

??. Used when working with optionals where we have a variable that may have a value, or might be nil. var personalSite : String? let defaultSite = "http://www.lynda.com" var website = personalSite ?? defaultSite

What is a raw value

A raw value is a value that is assigned to a member of an enum.

functions

A sequence of instructions that perform a specific task, packaged up as a unit. func myFunction(){ println("this is a simple function") } myFunction() must use type annotation when using parameters also referred to as sub routines or procedures

Struct initializers

A struct can have an init method to provide initial values for the stored properties.

Struct stored properties

A struct has stored properties. It is known as stored properties because it has stored values.

Struct

A struct provides structured data that can hold multiple variables or attributes and behavior. These are what are known as properties (attribute) and methods (behavior). struct Car { var doors: Int var wheels: Int }

dictionary

AKA associative array, map, hashtable. Key / Value pair. not in a specific order. cannot have duplicate keys.

How do you unwrap an optional

Add a bang to the end of the variable

Arguments help us

Adopt generic behavior to our particular needs

In portrait orientation, all iPhones fall under:

Any Width, Regular Height. There's no way to target each device specifically.

API

Application programming interface — which is considered to be a black box.

Structures

Are simple containers for information that belongs together

We can creat a subclass

By putting its superclass after a colon.

computed property

Can only be variables. Don't store a value, returns a value based on other properties or calculations. A computed property should have a setter method for conveinence

Functions can have parameters with

default values which are assigned in the parameter. func doStuff(stuff stuff:String = "Walk dog"){ print(stuff) }

properties and methods are known as a struct's, emum or classes':

definition

deinit

deinit { // any necessary cleanup code such as closing resource connections }

When transitioning from a master to a detail view controller using a segue, which property do we use to access the detail view controller

destinationViewController

base class

does not subclass or inherit from any other class class Product { }

synchronous task:

doing something at once, and waiting until it is done

In an object we can access stored properties that are inside the definition of the object by using:

dot notation

To access properties we use the:

dot notation

We can call methods on objects using the:

dot notation

closure

lambda, block, anonymous functions. Cool bit — functions that accept a closure

Swift is a type safe

language

what keyword is implied with for in statement?

let

string interpolation

let final = "\(str1) \(str2) \(str3)"

concatenation

let final = str1 + str2 + str3

Sometimes its necessary for a subclass to adapt an inherited function to its particular needs by using the:

override keyword: override func wash(){ print("Car is clean baby!") }

When we add properties to the subclass we must add which keyword to the new init method?

override. override init(){ newProp = "dog" super.init() }

We can use one function in another function as a:

parameter

You can run a switch inside a function over a:

parameter

Function inputs are called:

parameters

When assigning a function to a constant or variable you do not use:

parenthesis

Type methods belong to the type it self, not the

particular instance of the class

Modifying a function to accept inputs allows us to

pass arguments to it

The job of a function is to

perform repetetive tasks

a reference type:

points to the actual value

To pass information from one view controller to another in a direct relationship using a segue we use the current view controllers'

prepare for seque method — prepareforSegue:sender

Adding the keyword final in front of a method or class

prevents the method or instance from being overridden

add item to dictionary

states["FL"] = "Florida", if key exists it gets overridden -- otherwise it adds it. Long form : states.updateValue("Nevada", forKey: "NV")

history of let

stems from math

Properties inside classes are known more formally as:

stored properties. They store the data inside each instance of the class

Within interface builder we work in a:

storyboard

A class is very much like a:

struct

struct example

struct Task { var description: String var status = Status() init(description: String){ self.description = description } }

String, Array, and Dictionary are implemented as:

structures

When referring to class hierarchy we say

subclass and superclass

To remove a key value pair you can use

subscript notation or a method. Assign nil via subscript: myDictionary["KO"] = nil, using a method: myDictionary.removeValueForKey("RN")

Types are set for both

keys and values [String: String]

when we create a new variable we say we are

declaring a variable

Segue objects manage transitioning from one:

view controller to another

The window acts as a container for the many

views that make up your app

In iOS you use windows and

views to present content on the screen

Interface builder lets us create our apps:

visually

remainder operator

%. Modulo. Tells leftover

unary increment operator

++

Runtime errors are errors that occur when we run our application, in contrast to compiler errors

, which is code that needs to be fixed before it can be run.

half-open range operator

..< — does not include the number on the right 0..<100

get count

.count, isEmpty

looping through arrays:

// Using while var index = 0 while index < todo.count { print(todo[index]) index++ }

strong type

// dictionaries are strongly typed. The keys and the values are separately typed var products : [Int:String]

initializer with parameter

//initializer with parameter init(name: String){ self.name = "John Doe" self.score = 10 }

Image views are ui elements that display:

1 image or an animated series of images

benefits to switch statements

1. A switch statement lets you switch on a range of values 2. A switch statement combines multiple pattern matches in a concise syntax 3. A switch statement can infer the type being switched on and provide compiler checks 4. A switch statement requires you to be exhaustive and consider every path your code can take

Three types of navigation styles

1. Hierarchical 2. Flat 3. Content or experience Driven

Why use structs?

1. Intended for straight-forward data structure tasks 2. Generally use them when your internal properties are all going to be simple value types If you would have created as a class in another language, you would use a class in swift.

Three parts of XCode

1. Interface builder — interface of app 2. Editor - write code 3. Debugger - fix problems

Advantages of value types:

1. Only one owner. 2. No dependencies on other owner 3. Copying is cheap over time

Two ways to provide fore initial values for class properties

1. Set value to empty string or other default value. 2. Create init method

Four pillars of iOS development

1. Tools - Xcode 6, iOS Simulator, Instruments 2. Language — Swift, Design patterns, supporting Frameworks 3. Design — App flow, Correct UI, Apple HIG 4. Rules of programming iOS — Default behavior, Customizing behavior, Signing and submitting apps

convenience initializer example:

Convenience inits call self.init class Product { let name: String let price: Double init(name: String, price: Double){ self.name = name self.price = price } } class Hotdog: Product { let relish: Bool init(relish: Bool, name: String, price: Double){ self.relish = relish super.init(name: name, price: price) } convenience init (name: String){ self.init(relish: true, name: name, price: 1.44) } } var chicago = Hotdog(name: "Chicago") chicago.price

How to add raw values to enum

Define type. enum Coin: Double { case Penny = 0.01, Nickel = 0.05, Dime = 0.10, Quarter = 0.25 }

Master Detail:

Design pattern where one screen shows high level of information. Clicking on an item on the master screen takes user to the detail view on another screen

asynchronous task:

Doing something behind the scenes and continuing the main work regardless of whether or not the background task is complete

enum

Enumerated types or Enums allow you to define a datatype with a list of possible values. Create one type that lets you group several related values together

real world emum

Helps prevent errors by defining set values to test againsts

Navigation can be broken down into three main style:

Hierarchical, Flat, Content or experience driven

HTTP

Hyper text transfer protocol

We can access an overridden function in the super class by

Including the keyword super

Except for optionals we need to

Initialize every instance variable

converting values

Int(), Double(), String()

basic data types

Int, Float, Double, String, Character, bool

A struct

Is a data type that bundles information

optional variables

Let us describe a situation where sometimes we have a value and sometimes we don't. Set like this: var temp : Int? This results in 'optional' text. To remove 'optional' text, add exclamation point after var: println("The temperature is \(temp!)") Referred to as forced unwrapping

Inside classes functions can

Model behavior

Classes

OOP -- object oriented programming

Thread:

Path of execution for code

To override an inherited function we

Reimplement it after the override keyword

How do we return multiple values from a function

Return via an array or a tuple

Stored properties in Structs

Store constant and variable values as part of a instance of a particular struct

stored properties

Structs can have stored properties which can be constants with default values

Properties associate values with a particular:

Structure, class, or enumeration

overflow checking

Swift does not allow values to overflow. If needed, overflow operators are available. &+, &-, &*, &/ &%

designated initializer

The initializer that must be used when creating an instance of your class. There must be one available for a class.

Designated initializer

The initializer that must be used when creating an instance of your class. There must be one per class.

concurrency

The notion of multiple things happening at once

return a value

The return type of a function comes after input parameters. Must have reachable return statement. func myFunction() -> String { return "Hello" }

short circuit evaluation

These operators are lazy and would like to do the least amount of work possible. They return true or false after the first succesful test

T or F — A normal variable must be initialized before we attempt to use it

True

T or F : we can define 2 names for the same parameter

True. A function parameter can have a different internal and external name. We are changing the internal parameter

A view is an instance of the:

UIView class

Forced unwrapping

When we are sure the optional has a value. Must test if value is not nil

We can use a struct

Whenever we want to encapsulate a few simple values

operators

a && b. Joins one logical operator to another. a || B ! means not

types

a construct to represent different kinds of data like letters or numbers

string interpolation can include

a function call

Convenience initializer are:

created so that any if any default values can be specified, they are specified and you only have a minimal set of parameters

reference type

a reference to the original value is copied. Passing a reference to a location in memory

programming is

a series of instructions

What is an instance

a struct is a blue print, from it you can create instances

value type

a value type is a type whose value is copied when it is assigned to a variable or constant, or when it is passed to a function • Has only one owner • No dependencies on other owners • copying is cheap over time • comparing values is easy

The showing and hiding of information is handled by:

a view controller

protocol

a way to standardize some behavior across classes without worrying about inheritance or any formal relationship.

An entry point is a way to

access a view controller

A segue overrides an:

action

target actions

action and target is tied to event

extensions

add methods and properties to existing types

How do you create an optional?

add question mark to end of type, such as: var temp : Int?

typing

all variables are of a specific data type

Struct

allows you to create a new datatype

When we provide a value for a parameter it is called:

an argument

The filter function filters items in an array and returns:

an array

Simple statements are the most common and consist of either:

an expression or a declaration.

Logical operators unfold their true potential in combination with:

an if statement

when you create a variable with a class or struct it is called:

an instance

navigation bar

appear on the top of an app screen, just below the status bar and displays current level you are on and the path you took to get there

simplest way to add item to array is the

append method: todo.append("pup to vet")

Another way to add items to array is by

appending an array: todo += ["order book"]

Functions can be used inside other functions using the

arguments from the wrapping function

two built in collection types

array, dictionary -- arrays are zero-based. Arrays are type-safe. No mixing and matching of types. Mutable when created with var. Immutable when created with let

A variable number of parameters can be treated as an:

array. func sum(numbers: Int...){ var s = 0 for number in numbers { s += number } print(s) } sum(1,2,4)

Higher order functions are functions that take one or more functions:

as their input

raw values with emumns

assign raw values to enums to easily do something with those values. Must be unique

Putting information into a variable is called

assigning

To add a new key to a dictionary use the:

assignment operator: myDictionary["KO"] = "knocked out"

Each scene has an:

associated view hieracrcy

To solve problems with layout in iOS we use:

autolayout

Property observers fire:

before and after a property is modified. willSet {//right before the change} didSet{//right after the change} var weight = 100 { willSet { print("about to change name to \(newValue)") } didSet { print("changed weight from \(oldValue)") } }

Compiler errors need to be fixed:

before our app can run

1 + 1 is an example of

binary

square brackets are also referred to as

box brackets

parameters

by default input parameter is contstant, not a variable, using var when you declare makes it mutable

A view consist of everything a user

can see

Using self inside the init method helps keep the code clear. Also, self is specified because of a naming conflict. Self refers to the stored property, and the second is the local parameter that has been passed.

class Heros { let name: String let level: Int init(name:String, level: Int){ self.name = name self.level = level } }

class

class Player { // properties var name : String = "John Doe" var score : Int = 0 // methods func description() -> String { return ("Player \(name) has a score of \(score)") } } // instantiate a new Player object var jake = Player()

inheritence

class PremierPlayer : Player { // new class name followed by colon and class we want to inherit from }

Super.init example

class Presidents: Heros { let country: String init(country: String, name: String, level: Int) { self.country = country super.init(name: name, level: level) } }

designated initialer example

class Product { var title: String var 120: Double = 0.0 init(title: String, price: Double){ self.title = title self.price = price } }

class example:

class Shape { var sides: Double var name: String init(sides: Double, name: String){ self.sides = sides self.name = name } } class Square : Shape { var sideLength: Double var area: Double { get { return sideLength * sideLength } set { sideLength = sqrt(newValue) } } init(sideLength: Double , sides: Double, name: String) { self.sideLength = sideLength super.init(sides: sides, name: name) } convenience init(sideLength: Double){ self.init(sideLength: sideLength, sides: 4.0, name: "Square") } } var theSquare = Square(sideLength: 20.3)

key differentiator between struct and class:

class is reference type, struct is value type

A push segue adds a view to a navigation stack in which the information is:

clearly connected to the previous screen

deinit is used to

close connections to resources

tuple

collection of values. Returning a tuple: func getCurrentSongAndDuration() -> (String, Int){ return("Moonlight in Vermont", 210) } Set of values wrapped in parenthesis

The model

collects data, performs logic on it, and gets it ready for use

syntax

commands, special words, and punctuation you use to put together a program

The model does not

communicate with the view

comparison operators are binary operators used to

compare the indentity of two values, return true or false

type inference

compiler looks at code and infers type. Let compiler infer if it is obvious, if not declare it.

Another type of property is known as a

computed property. Uses getter and setter methods

We need to be sure to write:

concurrent code in Swift

When uploading or downloading creating a:

configuration object is the first step you must take.

You can assign a function to a:

constant or varible

Parameters are assigned as:

constants, but can be changed to a variable using the var keyword

to represent the type of an array we use the type of its:

content and place within square brackets -- [String]

a value type makes a:

copy

range operate

create a range between two numbers. 0...3 -- Closed range operator for number in 1...10 { print("\(number) times 5 is equal to \(number * 5)") }

let

creates contstant

When returning the value as a tuple we have access to the return value via

dot notation. func doStuff(stuff stuff:String = "Walk dog", stuff2:String = "Walk dog Again") -> (String, String){ return(stuff, stuff2) } let result = doStuff() result.0

A views purpose is to

draw to the screen and display data from the model object

Instance level class properties have that name because

each instance of the class receives those values

When returning tuples, you can assign a name to:

each return type. func doStuff(stuff stuff:String = "Walk dog", stuff2:String = "Walk dog Again") -> (Stuff1: String, Stuff2:String){ return(stuff, stuff2) } let result = doStuff() result.Stuff1

to enable push segue we must

embed our view controller inside a navigation controller -- editor/embed in/navigation controller

enum example using self

enum Day : Int { case Monday = 1, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday func daysTillWeekend() -> Int { return Day.Saturday.rawValue - self.rawValue } } var day = Day.Monday day.daysTillWeekend()

example of initializer method with emum

enum Day : Int { case Monday = 1, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday init() { self = .Monday } func daysTillWeekend() -> Int { return Day.Saturday.rawValue - self.rawValue } } var today = Day()

enum example

enum Day { case Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday } func weekdayOrWeekend(dayOfWeek dayOfWeek: Day) -> String { switch dayOfWeek { case Day.Monday, Day.Tuesday, Day.Wednesday, Day.Thursday, Day.Friday: return "It's a weekday" case Day.Saturday, Day.Sunday: return "Yah! It's the weekend" default: return "Not a valid day" } } weekdayOrWeekend(dayOfWeek: Day.Monday)

raw value assignment example

enum Day: Int { case Monday = 1, Tuesday = 2, Wednesday = 3, Thursday = 4, Friday = 5, Saturday = 6, Sunday = 7 }

enums

enum SeatPreference { //seat preference is the new type // each case is a member value of the enumeration // typically written with uppercase first letter case Window case Middle case Aisle case NoPreference }

enum example

enum Status { case Doing, Pending, Completed init() { self = .Pending } }

associated values (with enums)

enum Status { case Success(String) case Failure(String) } let downloadStatus = Status.Failure("Network connection unavailable") When you want to pass it a value, you use the same construct. Lets you add an associated value when you create a new instance of the type. When you want to extract the value you give it a constant in parenthesis. switch downloadStatus { case .Success(let success): print(success) case .Failure(let failure): print(failure) }

Buttons have a few different states which is an:

enum called UIControlState. The default state is normal. Other states are: highlighted, selected, and so on

A closure is a combination of a function and an:

environment of captured variables.

Single responsibility principle:

every class should have single responsiblity

var

every variable in Swift is declared with keyword var. A variable is a way of holding on to some data

Control flow statements are good for:

executing code based on logical conditions

together, the operands and the operator is known as an

expression

calling a function is an:

expression, so we can assign the value to a variable or a constant

Parameters in a swift function can have both a

external parameter name and an internal parameter name

Functions are treated as:

first class citizens or objects

adding to the end of an array

flavors.append("new flavor") flavors += ["Flavor"]

insert at specific location

flavors.insert("fudge", atIndex: 2)

remove items

flavors.removeLast() flavors.removeAtIndex(3)

A structure is a:

flexible data type that allows you to group together related values and model them as a unit

Control flow statements are used to control the:

flow of execution in a program.

iterate over values

for (key, value) in states { println("\(key) is short for \(value)") }

for in

for individual-item in some-collection { }

@IBAction lets:

interface Builder know that we have a method in code that is associated with a button

A while loop can be nested inside a:

for loop var y = 1 for x in 1...5 { while y < 2 { print(y) y++ } }

We can return one function:

from another

example of map function:

func doubler(i : Int) -> Int { return i * 2 } let doubleFunction = doubler doubleFunction(20) let numbers = [1,2,3,4,5] let doubledNumbers = numbers.map(doubleFunction)

struct methods

func fullName() -> String { return self.firstName + " " + self.lastName }

isDivisible function

func isDivisible(num1: Int, num2: Int) -> Bool?{ if(num1 % num2 == 0){ return true } else { return nil } } if let result = isDivisible(13, num2: 3){ print("divisible") } else { print("Not Divisible") }

pass in a parameter to function

func myFunction( name : String ){ println("Hello \(name)") } myFunction("Jane")

Using default parameter values

function myFunction (name : string = "John Doe") { } must use named data if you want to override. myFunction(name: "Jane")

Methods are:

functions associated to a particular type

The 2 actions associated with properties are:

getting a value and setting a value

getter and setter methods

get{} or set{} goes inside computed properties class Temperature { var celsius: Float = 0.0 var fahrenheit: Float { get { return (celsius * 1.8) + 32 } } }

Closures allow us to to build up:

higher order function

switch

http://austinzheng.com/2014/12/16/swift-pattern-matching-switch/ A switch statement compares some value so it can compare it against several matching patterns. evaluating a single item reacting to multiple possible values. Switch statements must be exhaustive. Can provide range of values with range operator switch valueToConsider { case value1:respond to value1 case value2: respond to value2 default: do something else } using an array and for in: let airportCodes = ["LGA", "LHR", "CDG", "HKG", "DXB", "JKL"] for airportCode in airportCodes { switch airportCode { case "LGA", "SFO": print("La Guaria") case "LHR": print("That is lhr") default: print("I Dont know") } } You can test on multiple cases separated by a comma You can also switch over a range of values: var randomTemp = Int(arc4random_uniform(UInt32(150))) switch randomTemp { case 0..<32: print("Dont leave home") case 32...45: print("You will need a jacket") case 45...70: print("You will need a swearer") default: print("Too hot") } You can also run a switch on key, value pairs: let world = [ "BEL": "Brussels", "LIE": "Vaduz", "BGR": "Sofia", "USA": "Washington D.C.", "MEX": "Mexico City", "BRA": "Brasilia", "IND": "New Delhi", "VNM": "Hanoi"] for (key, value) in world { // Enter your code below switch key { case "BEL", "LIE", "BGR": europeanCapitals.append(value) case "IND", "VNM": asianCapitals.append(value) default: otherCapitals.append(value) } // End code }

Clean up your JSON with this:

http://prettyjson.com/

How to pull data from a pList

if let plistPath = NSBundle.mainBundle().pathForResource("CrazyInformation", ofType: "plist") { let currentCrazyInformation = NSDictionary(contentsOfFile: plistPath) } // inside view did load method

optional binding

if let result = states["NV"] { println("The state name is \(result)") } else { println("No matching key found") } // If key has a value, it gets assigned to constant

How to test for nil value in an optional

if temperature != nil { print(temperature!) }

convenience initializer

if there are any default values that can be specified, they are specified with a minimal set of parameters. Must start with keyword "convenience", which will call a designated initializer in return. It will only call the designated initializer of your current class. You cannot call the super initializer

Type inference

if values are obvious

a constant is known and an

immutable type

A navigation bar is contained

in a navigation controller

The navigation bar best enables us to navigate an

information driven app

push segue

information from the push segue is clearly connected to the previous screen

The most unique feature of a class is:

inheritance

sub class

inherits properties, methods, and initializers

initialzier

init(){ name = "John Doe" score = 0 }

You can also hardcode

initial values in an init method. init(){ name = "John Doe" score = 0 }

The process for preparing a struct for use is called:

initialization, and involves setting the value each stored property on the instance.

A subclass can have it's own init method as long as you:

initialize all the properties

You must initialize the properties that are in the current class first, before you:

initialize the properties that are in the super class

The advantage of optional properties is that they do not need to be:

initialized

Enums can have methods as well as

initializers. enum Size { case Small, Medium, Large init(){ self = .Small } }

To add element inside an existing array use the

insert method

string interpolation

insert new content into string. \("the string")

A variable created inside a function only exists:

inside that function

An instance method can only be called after we have an actual:

instance

Using the blueprint, we then create an:

instance

Self means the current:

instance of this class. self.name refers to the instance, not the class property

Except for optionals, we need to initialize every

instance variable

IDE

integrated development environment

A dictionary is an unordered list of

key-value pairs

When you don't want your stored properties to be mutated, you specify them as:

lets instead of vars inside the class construction. This is regardless of whether or not the instance is declared with let or var. They will be assigned in instantiation

view controller

links app data to visual appearance

A view controller:

links the app's data to its visual appearance

Any variable or constant created inside a function is called a

local variable

Just like other types, enums can contain:

methods

classes also have:

methods

One time actions are often presented in a:

modal

Object oriented programming is a style of programming where we:

model information into data structures.

a var is known as a

mutable type

when we call the function we add the

named parameters somefunc(par1: 100, para2: 200)

A property list or plist is a file that organizes data into:

named values and lists of values much like a dictionary or array. They are easy to read into NS dictionaries.

The hierarchical style of navigation is enabled by the:

navigation bar

In the setter method we use which keyword to set the value?

newValue

All networking code should be in a background cue to:

not block the UI and make it unresponsive

In regard to classes, you instantiate new:

objects of said class.

Size classes lets us build our app

on a canvas that is not tied to a specific device, but rather all devices

A struct does not need an initializer because:

one is provided by default.

infix operators go between the two

operands

the numbers 1 and 1 are referred to as

operands

array

ordered list of values. A list is a good mental model

The return keyword is used to:

output a value from a function

A navigation bar is contained in a navigation controller which is a:

programatic object which manages a the display of a hierarchy of views.

A navigation controller is a:

programmatic object that manages the display of a hierarchy or order of views

These instructions are provided by a

programming language

Structs can contain

properties and methods

enum methods

put functions inside enum declaration

Labels enable function calls to

read nicer. sayHello(to: "Pasan", and: "Gabe")

Classes are passed by:

reference — in other words, when assigned to another variable or passed to a function, a reference to the original object is passed

To remove an element inside an existing array use the

remove at index function, todo.removeAtIndex(0)

REST

representational state transfer.

POST is used to create, while GET is used to:

retrieve

a function's output is known as a

return type

When using a closure, the argument signature:

returns a value. func myFunc(y: Int -> Int){ // Give me a function } This represents a function that needs an Integer as an argument and returns another one. If we want to pass more arguments, we need to put them in brackets and separate them with commas: (Int, String, Double)

The logical AND operator:

returns the boolean value true if both operands are true and returns false otherwise.

The logical or operator:

returns the boolean value true if either or both operands is true and returns false otherwise.

Classes are yet another powerful concept we can use to make our code

reusable and understandable

Runtime errors only occur when we:

run our app

A storyboard is composed of multiple:

scenes

An enum can have a method that runs a switch on:

self, which allows a unique message to each type. enum Type { case Private, Work func description() -> String { switch self { case .Private: return "It is private" case .Work: return "It is work" } } } var myType = Type.Private myType.description()

function

self-contained chunks of code that perform a specific task

With the NSURL session API, your app creates a:

session object which carries out your networking tasks.

An initializizer is a special instance method that:

sets up our object ready for use.

Structs can have initializers by:

setting default values for stored properties struct Contact { let firstName: String let lastName: String func returnName() -> String { return self.firstName + " " + self.lastName } init(fName: String, lName: String){ self.firstName = fName self.lastName = lName } } var person = Contact(fName: "Hob", lName: "Hind"

@IBOutlet

shows text

In Xcode, pressing command-1:

shows your files

Self contained actions are not part of:

some other workflow

Optionals let us describe a situation where:

sometimes we have a value and sometimes we don't

operator is a :

special symbol or phrase that you use to check, change, or combine values

Subclassing helps us adapt generic code to our:

specific needs

repeat while:

statements in body are executed first, then the condition is verified. Guarantees one pass through body of loop: repeat { print("I am in a repeat loop!") counter++ } while counter <

to remove key/value pair

states["DE"] = nil, states.removeValueForKey("CA")

To access the overridden function, we can use the:

super keyword: class RaceCar: Car { var nitro: Bool? override func wash(){ print("Car is clean baby!") super.wash() } }

Whenever we implement init() in our subclass, we need to call:

super.init() to let the superclass do its initializing class Vehicle { var wheels: Int? } class Bike: Vehicle { override init(){ super.init() self.wheels = 2 } }

you can call the _____

super.int method after performing custom initialiazation

base class is a:

superclass of subclass

Before we can change the values of inherited variables in our init() function of a subclass, we need to allow our

superclass to set its initial values class Animal { var flying = false } class Swifty: Animal { override init() { super.init() self.flying = true } } var mySwift = Swifty()

A first class object:

supports all of the operations generally available to other types

The set of rules in programming is called

syntax

target action:

the action and its target is tied to an event, when the touch event occurs on the controller, the sequence is initiated

The advantage of objects is that we can associate a function with:

the data contained inside.

When using a setter method, the newValue keyword provides

the entire value

The Controller acts as:

the intermediary and controls the logic between the two

To grab items in array use

the item's index: let firstTask = todo[3] (subscript syntax)

Navigation bar shows two important things:

the level in the hierarchy as well as the path taken to get there

We can perform a function on each item in an array by using:

the map function

Lazy properties: the property is only accessed when

the method is called: lazy var bonus = getBonus()

A Method signature includes

the name, parameters, and return type

Method signature

the name, parameters, and the return type

We can override a method by using:

the override keyword

the parenthesis are where

the parameters go

The function that accepts another function can call:

the passed function using the name of the argument

When we press the button to initiate our segue, our view controller calls

the prepareforSegue:sender: method

The subclass is of type

the super class. This is what the colon means

When overriding methods in a subclass we have the option to call

the super.methodName()

string

the syntax for creating a string literal: let myString = "my string"

When the compiler infers the type for us we say

the type annotation is implicit

a NSURL configuration object is the first:

thing to do -- it provides the rules

No return type indicates that the return type is:

void. Also done like this: ->Void, ->()

No return type is a return type of:

void. We can explicitly declare this with the void keyword as the return type

We want to avoid:

tight couplings at all times

You use multiple views in different hierarchies :

to build how your app looks on the screen

Closures are especially useful when it comes to implementing callbacks because of the ability:

to capture variables

When a user interacts with the user interface the code gets:

top priority and is added to the main cue.

The best way to return multiple values is with a

tuple

You can also return a:

tuple from a function. func oneTwo() -> (Int, Int) { return (1, 2) } let (x, y) = oneTwo()

A method is a function associated to a specific:

type

Enums create a new:

type

methods are part of a:

type

a class is a new

type and is capitalized

Building blocks of programming language are called:

types

We use a combination of

types and grammar

Data can be many different

types.

There is a method that allows for updating key value pairs, it is called:

updateValue. myDictionary.updateValue("News you can use", forKey: "DB")

enum initializer

use init method inside enum: init(){ self = .Sunday } var today = Day() // results in Sunday as value gives the enum an initial value, this way you don't have to specify a value.

How to retrieve raw value

use keyword rawValue -- ex: Coin.Penny.rawValue

hierarchical

users make one choice per screen until they reach their destination

Stored properties store a:

value

We can return more than one:

value from a function using a tuple. Specify a tuple in the return type: func doStuff(stuff stuff:String = "Walk dog", stuff2:String = "Walk dog Again") -> (String, String){ return(stuff, stuff2) } doStuff()

Structures are passed by:

value — in other words when assigned to another variable or passed to a function, a structures value is copied

To create an instance of the struct named Lasagne:

var pastaDinner = Lasagne()

random number

var randNum = Int(arc4random_uniform(10))

Tuple return mult results

var result = getCurrentSongAndDuration() println("THE SONG IS \(result.0) and it's \(result.1)") Or, give names to the parameters: func getCurrentSongAndDuration() -> (name:String, length:Int){ return("Moonlight in Vermont", 210) } var result = getCurrentSongAndDuration() println("THE SONG IS \(result.name) and it's \(result.length)")

AnyObject and Any

var someObject : AnyObject var something : Any These are types, we can create variables and contstants of type AnyObject or

example of an optional with the if let syntax:

var temp: Int? temp = 10 if (temp != nil) { print(temp) } // optional binding if let theTemp = temp { print(temp) }

Structs and Classes are:

very similar

You can initiate multiple segues from a single

view controller

decompose tuple

ways to access individual items in tuple. One way is to assign a tuple to a tuple let myTuple = ("Jane", "Scott") let (myTuple1, myTuple2) = myTuple let (name, length) = getCurrentSongAndDuration() // names can be what ever you want

the keyword func indicates

we are declaring a new function

Request/response model:

we make a request in a certain place in a certain format

We need to pass a value to our initializer unless:

we provide initial values upon declaration or the variable is an optional

the curly braces are where

we specify our custom code

in order to keep parameters in the correct order

we use labels on the parameters

To pass information from one view controller to another using a segue

we use the current view controller's prepareforSegue:sender: method

'passing a parameter' is

whatever we specify between the parenthesis

A designated initializer is the main initializer to be used

when creating an instance of a class. There must be one for a class

orphaned outlet

when you create outlet and delete it in the code without getting rid of the interface builder connection

Initializer method with emum

whenever you create an instance with that enum, it will default to same value

loops

while, repeat while, and for. While example: var x = 0 while x <= 20 { print(x) x++ } repeat { statements } while condition

Each app has at least one:

window

A view manages a rectangular area within the

window in your app

for-in loop

works great for collection

can a subclass have its own initializer

yes

you must use string interpolation when

you are combining types

Struct Methods

you can create custom methods to extend its functionality or manipulate the data. func returnName() -> String { return self.firstName + " " + self.lastName }

Example of closure expressions

{(parameters) -> return type in statements }

Good candidates for emums

• Drop down menus for filters

Enum overview

• Let's you create a data type with possible values • Members can have raw values • Members can have associated values when creating an instance of that enum

enumerated types

• Lets you create a data type with possible values • Members can have Raw values • Members can have Associated values Great for limited set of values

overriding methods

• must use keyword override • the method signatures must match • when referring to the super class, use the keyword super


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