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iOS

Posted by arnavthecoder
arnavthecoder
3,453 Points

Error! Getter and Setter

Here is the code:

class Temperature {
    var celsius: Float = 0.0
    var fahrenheit: Float {
        get {
        return (celsius * 1.8) + 32.0
        }

        set  {
          return (fahrenheit - 32) / 1.8
        }
    }    
}

The error is:

swift_lint.swift:11:36: error: cannot invoke '-' with an argument list of type '(($T5), FloatLiteralConvertible)'
          return (fahrenheit - 32) / 1.8
                 ~~~~~~~~~~~~~~~~~~^~~~~

The instructions is :

We need to add getter and setter methods to the fahrenheit property of the Temperature class. Add a getter method to the access the value of the fahrenheit property. Then add a setter method. When the user assigns a value to the fahrenheit property, the setter method will calculate and assign a value to the celsius property. (Note: Celsius = (Fahrenheit-32)/1.8))

1 Answer

William Li
William Li
Courses Plus Student 26,868 Points

Yeah, return (newValue - 32) / 1.8 do this instead, because when calling a setter, you're setting a new value

William Li
William Li
Courses Plus Student 26,868 Points

Hi, It is for setter, not getter.

arnavthecoder
arnavthecoder
3,453 Points

The code is like this 

class Temperature {
    var celsius: Float = 0.0
    var fahrenheit: Float {
        get {
        return (celsius * 1.8) + 32.0
        }

        set  {
          return (newValue - 32) / 1.8
        }
    }    
}
William Li
William Li
Courses Plus Student 26,868 Points

Sorry about that, miss a thing here.

set {
  celsius = (newValue - 32) / 1.8
}
arnavthecoder
arnavthecoder
3,453 Points

THANK YOU SO MUCH!

William Li
William Li
Courses Plus Student 26,868 Points

Just remember this, getter, gets a property stored in the object, so it needs to return something; but setter, its purpose is to set a particular property of the object only, it doesn't need return.

arnavthecoder
arnavthecoder
3,453 Points

Got it.