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iOS Object-Oriented Swift Inheritance What is Inheritance?

Posted by Zachary Dorcinville
Zachary Dorcinville
1,659 Points

Not sure what the instance is supposed to consist of?

I'm not sure what to call in the instance.

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

  init(width:Double, height:Double){
    self.width = width
    self.height = height
  }
}
class RoundButton: Button {
var cornerRadius = 5.0
}
let rounded = RoundButton(cornerRadius: 5.0, height: Double, width: Double)

1 Answer

Stephen McMillan
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.a{fill-rule:evenodd;}techdegree seal-36
Stephen McMillan
iOS Development with Swift Techdegree Graduate 33,994 Points
Stephen McMillan
.a{fill-rule:evenodd;}techdegree seal-36
Stephen McMillan
iOS Development with Swift Techdegree Graduate 33,994 Points

You don't need to assign anything to the corner radius property because it has a default value set and there isn't an init for the RoundButton class. However because the RoundButton is a subclass of Button you still need to pass in the width and height.

let rounded = RoundButton(width: 5, height:5)