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iOS Intermediate Swift Properties Property Observers

Arius Eich
Arius Eich
2,769 Points

Setting a back ground color based off temperature with a property observer

I don't understand why this challenge is incorrect. I believe I have done everything correctly but it still will not let me pass. It says "make sure to set the back ground color based off the temperature value." Please help, thank you!

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

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

1 Answer

Magnus Hållberg
Magnus Hållberg
17,232 Points

There is just a small mistake, you forgot an "else". It should read:

        {
        didSet {
        if temperature > 80.0 {
          view.backgroundColor = .red
        }
        else if temperature < 40.0 {
          view.backgroundColor = .blue
        }
        else {
         view.backgroundColor = .green
        }
      }
    }