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iOS Object-Oriented Swift Inheritance Inheritance and Initializers

Posted by Brendan Drake
Brendan Drake
4,162 Points

Code Challenge Object Oriented Swift; Inheritance

The prompt is too problem solve and figure out why the code will not work. I added an super.init into my initializer for the subclass. Not sure what is going on here.

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

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

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

class RoundButton: Button {
  var cornerRadius: Double = 5.0

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

4 Answers

agreatdaytocode
agreatdaytocode
24,757 Points

Brendan,

Give this a try:

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){
    width += points
    height += points
  }
}
Brendan Drake
Brendan Drake
4,162 Points

Thanks again!!

agreatdaytocode
agreatdaytocode
24,757 Points

Anytime!

Eric Caine
Eric Caine
1,659 Points
Eric Caine
Eric Caine
1,659 Points

Why does this work? It doesn't seem to be what the challenge is asking for...? (But it does work!)

Peter Do
Peter Do
12,294 Points
Peter Do
Peter Do
12,294 Points

yeah I was trying the same as Brendan - I feel the same way Eric, I'm not sure that's what the question was asking for... but the code worked for the challenge?

Jacqueline Brehmer
Jacqueline Brehmer
1,336 Points
Jacqueline Brehmer
Jacqueline Brehmer
1,336 Points

I tried the code here for the challenge and it did not work. My initial stabs at it followed the same logic as Brendan's (almost the exact same code). Can anybody provide guidance on this one?