Swift – How to mutate a struct object when iterating over it

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struct are value types, thus in the for loop you are dealing with a copy.

Just as a test you might try this:

Swift 3:

struct Options {
   var backgroundColor = UIColor.black
}

var arrayOfMyStruct = [Options]()

for (index, _) in arrayOfMyStruct.enumerated() {
   arrayOfMyStruct[index].backgroundColor = UIColor.red
}

Swift 2:

struct Options {
    var backgroundColor = UIColor.blackColor()
}

var arrayOfMyStruct = [Options]()

for (index, _) in enumerate(arrayOfMyStruct) {
    arrayOfMyStruct[index].backgroundColor = UIColor.redColor() 
}

Here you just enumerate the index, and access directly the value stored in the array.

Hope this helps.

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