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iOS Object-Oriented Swift Properties Getter and Setter Methods

Shawn Fair
Shawn Fair
1,651 Points

Getter and Setter Methods Swift

What am i doing wrong

Temperature.swift
class Temperature {
    var celsius: Float = 0.0
    var fahrenheit: Float {
        get {
        return (celsius - 32)/1.8)
    } set { 
    fehrenheit: 90.0
    }
    }
}

1 Answer

Jhoan Arango
Jhoan Arango
14,575 Points

Hello there

  • Computed Properties

β€œIn addition to stored properties, classes, structures, and enumerations can define computed properties, which do not actually store a value. Instead, they provide a getter and an optional setter to retrieve and set other properties and values indirectly.”

So we know that a computed property is just a read-only property, where you can’t capture the value and use it somewhere else, it ONLY computes something and displays it (if you can say it like that).

class Temperature {
    var celsius: Float = 0.0
    var fahrenheit: Float {
    get {
        return (celsius * 1.8) + 32.0
        }
    set {
        celsius = (newValue - 32)/1.8 
    }
    }    
}

var temp = Temperature()

temp.fahrenheit = 89 // newValue being passed

In this challenge in order for us to set a value to the celsius property we can use the newValue keyword, this will set the value passed through the fahrenheit computed property.

Hope you understand a bit more.