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iOS Object-Oriented Swift Inheritance What is Inheritance?

Posted by Ceonn Bobst
Ceonn Bobst
1,788 Points

What is wrong?

?

Button.swift 
class Button {
  var width: Double
  var height: Double
  var cornerRadius: Double = 5.0

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

  let rounded = RoundButton
  }
  class RoundButton: Button {
  }  
}

2 Answers

Jonas Kristensen
Jonas Kristensen
2,738 Points
Jonas Kristensen
Jonas Kristensen
2,738 Points 
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
}

var rounded = RoundButton(width: 5.0, height: 5.0)
Jhoan Arango
Jhoan Arango
14,575 Points
Jhoan Arango
Jhoan Arango
14,575 Points

Hello Ceonn Bobst :

The challenge first ask you to create a class that inherits from the Button class, and then it ask you to give it a store property that must be a variable. Then at the end it tells you to create an instance of the RoundButton class that you created. 

class Button {
  var width: Double
  var height: Double

  init(width:Double, height:Double){
    self.width = width
    self.height = height
  }
}
// First part of the challenge
/* 
     We create a class called “RoundButton", and inherits from
     the class Button. So Button it’s the super class, and RoundButton 
     is the subclass. RoundButton is inheriting from it’s superclass. 
*/

class RoundButton: Button {
var cornerRadius = 5.0 // Stored property initialized with a value
}

// Then we create an instance of the class “RoundButton".

var rounded = RoundButton(width: 1.0 ,height: 2.0)

Any other questions please let me know :) Also if you find this the best answer, you can click the best answer option.