Class, Objects, Methods & Properties

Question 1

What is a Class?

Answer 1

A blueprint that we create to describe a component of our app.

Question 2

How do you create a Class? 2 Steps.

Answer 2

1. ) Type “Class” and give it a name.

2. ) Open { } and type: init ( ) { }

Question 3

What is init?

Answer 3

It’s an initializer. It’s a special type of method.

Question 4

What is init used for?

Answer 4

All Classes must have an initializer. Any code you put in-between the curly brackets within init, gets executed when a new object of a certain class is created.

Question 5

What is an object?

Answer 5

Objects are always created from the Class.

Question 6

How do you create an object?

Answer 6

Class name followed by ( )

Question 7

What is the easiest way to reference an object? Please give an example.

Answer 7

Turn the object into a variable.

Example: 
var a = Person( )

Question 8

What does the print line statement provide? Give it’s form.

Answer 8

Print Line statements are made to call out a newly created object.

Form: println (“This is what will print”)

Question 9

What is a method and what is it used for?

Answer 9

A named set of instructions that will be executed when called. They are created using the “func” keyword.
Expression:

func GiveMethodName ( ) { }

Question 10

What is written in the curly brackets of the method expression?

Answer 10

Inside the curly braces you write the code to execute when the method is called.

Question 11

The code inside the curly braces of the method expression would yield:

Answer 11

Println(“CalledMethod”) This line of code will only be executed if the func method is called.

Question 12

Once a method is created, how would you call it? Give an example.

Answer 12

Object.MethodName( ) The var is the object you created from the Class.

Example: Since I created the var to easily reference the object, it would be called by:

a.Walk( )

Question 13

Where are Properties created within a class? First, Second or Last?

Answer 13

Properties are always

Question 14

How do you call a method from the initializer?

Answer 14

Go up to inti ( ) { } and type:

self.MethodName( ) - self means call a method you own yourself.

Question 15

Give the expression for a Property. And give an example.

Answer 15

• var PropertyName: The data the property is going to store/track = an initial value

var Name:String = “Initial Name”

Question 16

What can be said about String?

Answer 16

**String is just a piece of text.

Question 17

What are the differences between the var declaration and a property declaration?

Answer 17

• Properties are used within the Class created

- Variables are used within the Method created.

Question 18

What expression would you use to call a property?

Answer 18

In order to call a property, it follows the same format as the method call.

object.propertyName

Question 19

What is a SubClass and why is it helpful?

Answer 19

A subclass inherits the properties and methods of another class. It allows you not to duplicate code.

Question 20

How would on create a subclass? Give one benefit of this subclass.

Answer 20

class Subclass Name : ParentClassName { }

This allows you to build new functionality within the subclass.

Question 21

What is another name for the parent class?

Answer 21

Super Class.

Question 22

How would you override a function of the parent class?

Answer 22

override func ParentClass Method( ) { }

Question 23

How do you call both functions of the Parent and Sub Class?

Answer 23

super.nameofthefunction within the subclass.