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iOS Intermediate Swift 2 Properties Property Observers

gurminder thind
gurminder thind
Courses Plus Student 10,062 Points

Help with Property Observer Challenge in Intermediate Swift

In Intermediate Swift 2.0 how to change background colour of the view based on didSet property of the temperature

class TemperatureController: UIViewController {
    var temperature: Double

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

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

2 Answers

John Roque Jorillo
John Roque Jorillo
13,117 Points

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

here hope this will help, please revisit the videos for better understanding :)