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

Posted by Michael McKinley
Michael McKinley
1,476 Points

Why can't I use the "+" symbol in this instance? Can someone please explain to me how to code this, I feel like I'm clos

prompt:

"We need to provide a means to increase the size of our Button. So we are going to add a method named incrementBy which will accept a parameter named points. (Within the method add points to the width and height properties)."

Button.swift 
class Button {
  var width: Double
  var height: Double

  init(width:Double, height:Double){
    self.width = width
    self.height = height
  }

func incrementBy(points: Double) {
  return (points + width) 
}
}
let button = Button(width: 8.0, height: 6.0)
button.incrementBy(4.0)

1 Answer

Aimee Ault
Aimee Ault
29,193 Points

Hey Michael!

So you've got the idea almost right, but just one small issue!

The incrementBy function doesn't return anything (the signature doesn't have a return type specified). Instead, you want to assign a new value to self.width and self.height (which are members of the Button class), like this:

self.width += points
self.height += points

Instead of returning a value :)