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iOS Object-Oriented Swift Inheritance Inheritance and Initializers

Posted by Ceonn Bobst
Ceonn Bobst
1,788 Points

What is wrong

Dont understand the issue?

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

  super.init (width:Double,height:Double,cornerRadius:Double){
  self.width = width
  self.height = height
  self.cornerRadius = cornerRadius
  }  
}
Meek D
Meek D
3,457 Points

what is the error or problem that you are having?

1 Answer

Dylan Shine
Dylan Shine
17,565 Points
Dylan Shine
Dylan Shine
17,565 Points

You haven't defined a super.init that takes those three arguments. This pattern is seen in Objective-C, but you could do something like this (aka idk if this is Swift..y):

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

// or you could just override it

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