patterns/observer/currentconditionsdisplay.d

module observer.currentconditionsdisplay;

import observer.displayelement;
import observer.observer;
import observer.weatherdata;
import std.stdio : writeln;
import std.format : format;

class CurrentConditionsDisplay : Observer, DisplayElement
{
private:
    float temperature;
    float humidity;
    WeatherData weatherData;
public:
    this(WeatherData weatherData)
    {
        this.weatherData = weatherData;
        weatherData.registerObserver(this);
    }

    override void update()
    {
        this.temperature = weatherData.getTemperature;
        this.humidity = weatherData.getHumidity;
        display();
    }

    override void display()
    {
        writeln("Current conditions: %3.1f".format(temperature), "F degrees and %3.1f%% humidity".format(humidity));
    }
}