UnexpectedOpposites.swift

let trumpImage = UIImage(named: "trump")
let borisImage = UIImage(named: "boris")

var personIsBoris = true
@IBOutlet weak var personImageView: UIImageView!

@IBOutlet weak var temperatureLabel: UILabel!

/// off = Celsius, on = Fahrenheit
var temperatureSwitchIsOn = true
@IBOutlet weak var temperatureSwitch: UISwitch!

@IBAction func temperatureSwitchToggled(_ sender: Any) {
    temperatureSwitchIsOn = temperatureSwitch.isOn
    personIsBoris = temperatureSwitch.isOn

    if temperatureSwitchIsOn {
        temperatureLabel.text = "32 °F"
    } else {
        temperatureLabel.text = "0 °C"
    }

    if personIsBoris {
        personImageView.image = borisImage
    } else {
        personImageView.image = trumpImage
    }
}