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iOS Intermediate Swift Properties Property Observers

swift_lint.swift:74:28: error: use of unresolved identifier 'CGFloat' view.backgroundColor = CGFloat(temperature)

what's the point?

observer.swift
class TemperatureController: UIViewController {
    var temperature: Double = 0.0 {

    didSet {

    view.backgroundColor = CGFloat(temperature)
    }

    }

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

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

        if temperature <= 80 {

         view.backgroundColor = .red

        } else if temperature >= 40 {

        view.backgroundColor = .blue

    } else {
    view.backgroundColor = .green

    }
}

2 Answers

tromben98
tromben98
13,273 Points
class TemperatureController: UIViewController {
    var temperature: Double {

   didSet {

            if temperature > 80 {
                view.backgroundColor = .red
            } else if temperature < 40 {
                view.backgroundColor = .blue
            }
            else {
                view.backgroundColor = .green
            }

        }
}

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

    override func viewDidLoad() {
        super.viewDidLoad()


}
}

thks again