How to override setter in Swift
What do you want to do with your custom setter? If you want the class to do something before/after the value is set, you can use willSet/didSet:
class TheSuperClass { var aVar = 0 } class SubClass: TheSuperClass { override var aVar: Int { willSet { print("WillSet aVar to \(newValue) from \(aVar)") } didSet { print("didSet aVar to \(aVar) from \(oldValue)") } } } let aSub = SubClass()aSub.aVar = 5Console Output:
WillSet aVar to 5 from 0
didSet aVar to 5 from 0
If, however, you want to completely change how the setter interacts with the superclass:
class SecondSubClass: TheSuperClass { override var aVar: Int { get { return super.aVar } set { print("Would have set aVar to \(newValue) from \(aVar)") } } } let secondSub = SecondSubClass()print(secondSub.aVar)secondSub.aVar = 5print(secondSub.aVar)Console output:
0
Would have set aVar to 5 from 0
0