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iOS Object-Oriented Swift Inheritance Overriding Methods

Posted by Timo Koko
Timo Koko
1,758 Points

Challenge compiler keeps returning the same error while the code is properly written according to Xcode

I have received the following error while the code works properly in my Xcode, I would not really know what they mean with this compiler error but it works properly in my Xcode version. Override, method signatures are correct. What would the problem be?

The compiler error (from the challenge): swift_lint.swift:21:17: error: argument names for method 'incrementBy(points:)' do not match those of overridden method 'incrementBy' override func incrementBy(points: Double = 7.0) ^ _

1 Answer

Marina Alenskaja
Marina Alenskaja
9,320 Points
Marina Alenskaja
Marina Alenskaja
9,320 Points

Hi!

This one is a bit tricky.. But you need to add the _ before the points argument in your method. This is due to the fact that you specify a default value in the method. So when using the method, the parentheses in it don't need to be filled - it will just use the default value. I hope that makes sense.. Like this:

class RoundButton: Button {
  var cornerRadius: Double = 5.0

  override func incrementBy(_ points: Double = 7.0){
    width += points
    height += points
  }
}

He actually talks about this in the video at 4:30 - and explains.

Timo Koko
Timo Koko
1,758 Points

Ah, thank you! I've re-watched the video, really helped me with understanding.