[swift] code log, day 3

iBooks 의 SWIFT 4 를 통해 언어 공부 중입니다. 이때 사용된 책 속의 코드 및 연습문제 등의 코드 로그입니다.

아래 코드들은 Github 에서도 다운받을 수 있습니다.

SWIFT_Playground_Excersice: https://github.com/youp-han/SWIFT_Playground_Excersice

//------------------------------------------------------------

// 코드 로그 입니다.

// Day 3

//Objects and Classes

class Shape{

    var numberOfSides = 0

    func simpleDescription() -> String {

        return "A shape with \(numberOfSides) sides."

    }

}

var shape = Shape()

shape.numberOfSides = 7

var shapeDescription = shape.simpleDescription();

print(shapeDescription)

//initializer

//when Initializing the class, the init variables must be declared

class NamedShape {

    var numberOfSides : Int = 0

    var name: String

    

    init(name: String){

        self.name = name

    }

    

    func simpleDescription() -> String{

        return "A Share with\(numberOfSides) sides, and the name is \(name)"

    }

}

var testname = NamedShape(name:"Mike")

print(testname.simpleDescription())

//superclass inherritance

class Square: NamedShape{

    var sideLength: Double

    init(sideLength: Double, name: String){

        self.sideLength = sideLength

        super.init(name: name)

        numberOfSides = 4

    }

    

    func area() -> Double {

        return sideLength * sideLength

    }

    

    override func simpleDescription() -> String {

        return "A square with sides of lengh \(sideLength)"

    }

}

let test = Square(sideLength: 5.2, name: "my Test Square")

print(test.area())

print(test.numberOfSides)

print(test.simpleDescription())

//excercise : area of Circle

class Circle: NamedShape{

    var radius: Double

    let pi: Double = 3.141592

    init(radius: Double, name: String){

        self.radius = radius

        super.init(name:name)

        numberOfSides = 0

    }

    

    func area() -> Double{

        return radius * radius * pi

    }

    

    override func simpleDescription() -> String {

        return "A circle with radius of \(radius)"

    }

}

var testCircle = Circle(radius: 4.0, name: "my Test Circle")

print(testCircle.area())

print(testCircle.simpleDescription())

//getter, setter of properties

class EquilateralTriangle: NamedShape{

    var sideLength: Double = 0.0

    

    init(sideLength: Double, name: String){

        self.sideLength = sideLength

        super.init(name: name)

        numberOfSides = 3

    }

    

    var perimeter: Double{

        get{

            return 3.0 * sideLength

        }

        set{

            sideLength = newValue / 3.0

        }

    }

    

    override func simpleDescription() -> String {

        return "An equilateral triangle with sides of length\(sideLength)"

    }

}

var triagle = EquilateralTriangle(sideLength: 3.1, name: "a Triagle")

print(triagle.perimeter)

triagle.perimeter = 9.9

print(triagle.sideLength)

class TriangleAndSquare{

    

    var triangle:EquilateralTriangle{

        willSet{

            square.sideLength = newValue.sideLength

        }

    }

    

    var square: Square{

        willSet{

            triagle.sideLength = newValue.sideLength

        }

    }

    

    init(size: Double, name: String){

        square = Square(sideLength: size, name: name)

        triangle = EquilateralTriangle(sideLength: size, name: name)

    }

}

var triangleAndSquare = TriangleAndSquare(size: 10, name: "Another Test Shape")

print(triangleAndSquare.square.sideLength)

print(triangleAndSquare.triangle.sideLength)

triangleAndSquare.square = Square(sideLength: 50, name: "Larger Square")

print(triangleAndSquare.triangle.sideLength)

print(triangleAndSquare.square.sideLength)

let optionalSquare: Square? = Square(sideLength: 2.5, name: "optional Square")

let sideLength = optionalSquare?.sideLength

print("optional sidelength = \(sideLength)")