//constructor sets default subject and output
        public WeatherDisplay(IWeatherSubject subject, ListBox output)
        {
            this.output = output;

            //adds observer to monitor
            subject.AddObserver(this);

            //sets values to 0
            currentHumidity = 0;
            currentPressure = 0;
            currentTemp     = 0;
        }
        //constructor sets default subject and output
        public WeatherDisplay(IWeatherSubject subject, ListBox output)
        {
            this.output = output;

            //adds observer to monitor
            subject.AddObserver(this);

            //sets values to 0
            currentHumidity = 0;
            currentPressure = 0;
            currentTemp = 0;
        }
 public WeatherObserver(IWeatherSubject weatherSubject)
 {
     measurements = new Measurements();
     weatherSubject.AddObserver(this);
 }