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

Devin Scheu
Devin Scheu
66,191 Points
Posted by Devin Scheu
Devin Scheu
66,191 Points

Swift Help

Question: 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).

My Code:

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){
    width = self.points + width
    height = self.points + height
  }
}

1 Answer

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

points is a local parameter, not a property, so dont use self.points, just points. Also note the name needs to be incrementBy, not incrementBY:

func incrementBy(points:Double){
    width = points + width
    height = points + height
  }

another way to do the increment is to use +=, which is a bit cleaner:

func incrementBy(points:Double){
    width += points 
    height += points 
  }