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iOS Object-Oriented Swift Classes and Objects Classes and Their Methods

Alex Nelsen
Alex Nelsen
Courses Plus Student 2,977 Points

What is going on here?

In this challenge, unlike others before there seem to be a few leaps that I am missing. I have looked for clues in other questions and I get this far. But it seems that the Button.incrementBy is looking for type Button and it fails both on Xcode and in the exercise. (Sometimes, due to the updates I assume, this is not so. the playground fails but the exercise does not)

Any help will be appreciated.

class Button {

    var width: Double
    var height: Double

    init(width: Double, height: Double) {
        self.width = width
        self.height = height
    func incrementBy(points: Double)  {
       self.width = width + points
        self.height = height + points
var newButton = Button(width: 3, height: 10)

1 Answer

Hi Alex,

The incrementBy function is not a "class/type method", instead it is an "instance method". Because of this, you want to call incrementBy on the instance that you created.

For example:


Hope this helps.