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iOS Intermediate Swift 2 Properties Property Observers

Posted by patrick ridd
patrick ridd
21,011 Points

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
21,729 Points
Schaffer Robichaux
Schaffer Robichaux
21,729 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()
    }
}
patrick ridd
patrick ridd
21,011 Points

Okay that makes more sense now. Thanks Schaffer!