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iOS Object-Oriented Swift Inheritance Overriding Methods

Posted by Karl Bjorkman
Karl Bjorkman
1,808 Points

Ahh! What is wrong with my code here? I'm looking at the override method in my subclass.

Any suggestions will be much appreciated.

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 += points
    height += points
  }
}

class RoundButton: Button {
  var cornerRadius: Double = 5.0

  override func incrementBy(points: Double = 7.0) -> Double {
    return super.incrementBy(points)
  }

}

1 Answer

William Li
PLUS
William Li
Courses Plus Student 26,868 Points
William Li
William Li
Courses Plus Student 26,868 Points

Hi, there, there're errors in 3 spots.

  • You need to put in an underscore _ in the argument passing for overriding incrementBy function.
  • This function doesn't have a return type
  • and doesn't need the return keyword.
    override func incrementBy(_ points: Double = 7.0) {
      super.incrementBy(points)
  }