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iOS Object-Oriented Swift Properties Getter and Setter Methods

keith frazier
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keith frazier
Python Development Techdegree Student 5,771 Points
Posted by keith frazier
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keith frazier
Python Development Techdegree Student 5,771 Points

set method

Im trying to write a set method for a computed property, the preview tab is telling me "UInt8 is not convertible to 'double'", but every number in my code is already a double and the variables are also set to be doubles, so I do not understand what i have to correct.

Temperature.swift 
class Temperature {
    var celsius: Double = 0.0
    var fahrenheit: Double {
       get { return (celsius * 1.8) + 32.0 }
       set { celsius = (fahrenheit-32.0) / 1.8 (newValue) }
    }    
}
Dan Oswalt
Dan Oswalt
23,438 Points

Where is newValue declared? (I ask because I've never done getter / setter, I don't understand where this comes from)

keith frazier
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keith frazier
Python Development Techdegree Student 5,771 Points
keith frazier
.a{fill-rule:evenodd;}techdegree
keith frazier
Python Development Techdegree Student 5,771 Points

I have newValue declared after the calculation in the curly braces of the setter method so that the fahrenheit can be supplied to the class so the celsius could be indirectly set.

1 Answer

Mindy Sandilands
Mindy Sandilands
15,743 Points
Mindy Sandilands
Mindy Sandilands
15,743 Points 
import UIKit

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

The code above should work for this challenge. When using the setter for fahrenheit, the new value has the implicit name newValue. You are using the setter on fahrenheit so it should not be called within the setter.
Hope this helps, Mindy