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iOS Intermediate Swift 2 Properties Property Observers

Property Observers Code challenge in Intermediate Swift.

My code is compiling and the conditional statements are correct, but it still says I'm not setting the colors correctly?

observer.swift
class TemperatureController: UIViewController {
    var temperature: Double = 0 {
      didSet(newValue) {
        if newValue > 80.0 {
          self.view.backgroundColor = UIColor.redColor()
        } else if newValue < 40.0 {
         view.backgroundColor = UIColor.blueColor() 
        } else {
          view.backgroundColor = UIColor.greenColor()
        }
      }
    }

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

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

1 Answer

Schaffer Robichaux
Schaffer Robichaux
21,728 Points

Patrick, looks like you are setting your boolean comparisons in the if...else property observer to didSet's default property newValue; however, the comparison should be with the temperature variable. -Cheers

import UIKit

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

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

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

Okay that makes more sense now. Thanks Schaffer!