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iOS Object-Oriented Swift Complex Data Structures Methods

Kanish Chhabra
Kanish Chhabra
2,151 Points
Posted by Kanish Chhabra
Kanish Chhabra
2,151 Points

What are getter and setter properties?

I need an explanation of getter and setter properties with and example, I read about on Apple's website which was linked in the teacher's notes but they've not used simple language so I was not able to understand it. Please help :)

Lukas G.
Lukas G.
4,842 Points
Lukas G.
Lukas G.
4,842 Points

Hello Kanish, I hope I can clean things up. I think you are talking about calculated values here. 1) getter - getter is what you... well, get when you access a property. Example:

var someProperty = 4
var calculatedProperty: Int {
   get {
      return someProperty * 2
   }
}

let answer = calculatedProperty

In this case you get 8 back. 2) setter - the name setter could be a little misleading, since you don't set calculated values. What is does is, it sets other values when the calculatedProperty is calculated. 

var someProperty = 4
var anotherProperty = 0

var calculatedProperty: Int {
   get {
      return someProperty * 2
   }
   set {
      anotherProperty = newValue / 4
   }
}

Now, when you calculate "anotherProperty" will also be set. You can access the newly calculated value with "newValue". You can also explicitly give it a name by: 

set (myCustomName) {
   print(myCustomName)
}