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iOS Object-Oriented Swift Properties Getter and Setter Methods

Alex Bruce
Alex Bruce
1,622 Points

Please take a look at my code and tell me whats up.

Please just tell me what I did wrong?

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

1 Answer

You're pretty close here. Your get method works great, it accesses the value and returns it. Your set method however is fundamentally incorrect. When writing a set method, you must remember that a value inside of this class is going to be changed by an outside source. Your current setup will just return a value, which is what a get method would do. To properly use the set method, you'll need to assign the argument given externally to a variable inside your class, and in this case it's your celsius variable.

So you know that you'll start your set method like this -

celsius = 

Now you'll need to remember the default name of the argument passed in, which is newValue. so celsius = newValue is the gist of what you need, but that's still not the correct answer. This is where it gets a little tricky, because you need to calculate the newValue passed in to convert it to Celsius. The formula for this is Celsius = (Fahrenheit - 32) / 1.8 (as per the challenge description).

Since you are converting a Fahrenheit number to a Celsius number with this setter method, do you see which part needs to be replaced with newValue? Try that, and if done properly, you should have your solution!