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iOS Intermediate Swift 2 Properties Property Observers

My answer isn't being accepted?

The error message is telling me to assign correct background color depending on the temperature... which I think I'm doing it correctly

class TemperatureController: UIViewController {
var temperature: Double = 0.0 {
didSet {
    if temperature > 80.0 {
        view.backgroundColor = UIColor.redColor()
    if temperature < 40.0 {
        view.backgroundColor = UIColor.greenColor()

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

    override func viewDidLoad() {
        view.backgroundColor = UIColor.whiteColor()

1 Answer


Check out the directions one more time. You should have 3 checks. To set the background color to red, blue, and green. You can use else if statement to solve this:

    var temperature: Double {
        didSet {
            if temperature > 80 {
                view.backgroundColor = UIColor.redColor() // red
            } else if temperature < 40 {
                view.backgroundColor = UIColor.blueColor() // blue
            } else {
                view.backgroundColor = UIColor.greenColor() // green

Awesome. Thanks Gary!