Value does not update in array

Question

When I searched on here I now know that almost everything in Swift is value based, not referenced base. I also have read that a class holds references. I tried my best, but below code will not print anything. If anyone could help me out printing out that line with the help of an array, that would be great :) (if it is possible ofcourse...).

Edit: I want 5 booleans in the array, in which they all have a didSet method. When I access them, that specific didSet will trigger. Is that possible?

class PowerUpBooleans{
    var boolean: Bool
    init(boolean: Bool){
        self.boolean = boolean
    }
}
var iWantToChangeThis = false{
        didSet{
            print("it worked")
        }
    }
    var powerUpBooleans = [PowerUpBooleans]()
override func viewDidLoad() {
        super.viewDidLoad()
        powerUpBooleans.append(PowerUpBooleans(boolean: iWantToChangeThis))
        powerUpBooleans[0].boolean = true
     }

@koropok yes but is there any to keep a reference to that boolean in an array? Or is this not possible at all? Thank you. — NoKey
– NoKey, Commented Aug 11, 2017 at 1:23
@koropok I will search for inout methods. I editted my question to make it more clear what I want. I want to have a didSet method on all the variables. — NoKey
– NoKey, Commented Aug 11, 2017 at 1:35
you can check this out. stackoverflow.com/questions/40745099/… — koropok
– koropok, Commented Aug 11, 2017 at 1:36

ribilynn · Accepted Answer · 2017-08-11 02:00:47Z

3

I guess you want set some booleans that have their own trigger.

As I known, making value type wrapped by class can only make it be reference type.

So try this.

class PowerUpBooleans{
  var boolean: Bool {
    didSet {
      trigger()
    }
  }
  var trigger: () -> ()

  init(boolean: Bool, trigger: @escaping () -> ()){
    self.boolean = boolean
    self.trigger = trigger
  }
}

let trigger1 = {
  print("one worked.")
}
let trigger2 = {
  print("two worked.")
}

var powerUpBooleans = [PowerUpBooleans]()
powerUpBooleans.append(PowerUpBooleans(boolean: false, trigger: trigger1))
powerUpBooleans.append(PowerUpBooleans(boolean: false, trigger: trigger2))
powerUpBooleans[0].boolean = true   // print one worked
powerUpBooleans[1].boolean = false  // print two worked

answered Aug 11, 2017 at 2:00

ribilynn

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Wyetro Over a year ago

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