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iOS Intermediate Swift Properties Property Observers

Gabriel Walsh
Gabriel Walsh
21,531 Points
Posted by Gabriel Walsh
Gabriel Walsh
21,531 Points

error: 'required' initializer 'init(coder:)' must be provided by subclass of 'UIViewController'

This passes the challenge but doesn't compile.

observer.swift 
class TemperatureController: UIViewController {
    var temperature: Double {
        didSet {
            if temperature > 80.0 {
                view.backgroundColor = UIColor.red
            } else if temperature < 40.0 {
                view.backgroundColor = UIColor.blue
            } else {
                view.backgroundColor = UIColor.green
            }
        }
    }

        init(temperature: Double) {
            self.temperature = temperature
            super.init()
        }

        override func viewDidLoad() {
            super.viewDidLoad()
            view.backgroundColor = .white
        }
}

2 Answers

Jonathan Ruiz
Jonathan Ruiz
2,998 Points
Jonathan Ruiz
Jonathan Ruiz
2,998 Points

Hi Gabriel do you mean it passed the challenge but doesn't compile in Xcode ? Did you import UIKIt in the Xcode playground ? you would need to to access the items like UIColor in that framework

Gabriel Walsh
Gabriel Walsh
21,531 Points
Gabriel Walsh
Gabriel Walsh
21,531 Points

Jonathan -

Thanks so much for your answer. I did indeed import UIKit to a single playground.

Thanks!

Jonathan Ruiz
Jonathan Ruiz
2,998 Points
Jonathan Ruiz
Jonathan Ruiz
2,998 Points

Hey Gabriel thats awesome ! I have had that issue before I wasn't sure but it sounded like that was the problem happy to help. Im still wrapping my head around this stuff to but I know that in order to access certain methods and code you have to use frameworks. Happy coding !