Initialization in Swift allows structs, classes, and enums to set initial values for properties and perform other initialization tasks. Designated initializers must call a designated initializer from the superclass, while convenience initializers can call any initializer from the same class but must ultimately call a designated initializer. Initialization can include custom parameters, set default values, and return nil in failable initializers if initialization fails.

1. Initialization
Johnson

2. Introduction
What is initialization?
Initialization is preparing instance class, struct or
enumeration for use

3. Setting initial value
struct Hello {
let sayHello: String
init(){
sayHello = “hello!!”
}
}

4. Setting initial value
struct Hello {
var sayHello = “hello!!”
}
let hello = Hello()

5. Custom parameter
struct Hello {
var sayHello: String
init(whatToSay word: String) {
sayHello = word
}
init(anotherHello word: String) {
sayHello = word
}
}
let saySomething = Hello(whatToSay: “HELLO”)
let sayAnother = Hello(anotherHello: “GREETING”)

6. Custom parameter
struct Hello {
var helloOne, helloTwo: String
init(helloOne: String, helloTwo: String) {
self.helloOne = helloOne
self.helloTwo = helloTwo
}
}
let hello = Hello(helloOne: “HELLO”, helloTwo:
“GREETING”)

7. Custom parameter
struct Hello {
var helloOne, helloTwo: String
init(_ word1: String, _ word2: String) {
helloOne = word1
helloTwo = word2
}
}
let hello = Hello(“HELLO”, “GREETING”)

8. Initializing delegate
1. A designated initializer must call a designated
initializer from its immediate superclass.
2. A convenience initializer must call another initializer
from the same class.
3. A convenience initializer must ultimately call a
designated initializer.

9. Failable initialization
init?(hello: String){
if hello.isEmpty{return nil}
self.hello = hello
}