Below is an easy counter code for basic programming.
First subclass Code:
((Counter)getWorld().getObjects(Counter.class).get(0)).add(1);
Second subclass Code:
import greenfoot.*; // (World, Actor, GreenfootImage, Greenfoot and MouseInfo)
import java.awt.Color;
/**
* A simple counter with graphical representation as an actor on screen.
*
* @author mik
* @version 1.0
*/
public class Counter extends Actor
{
private static final Color transparent = new Color(0,0,0,0);
private GreenfootImage background;
private int value;
private int target;
/**
* Create a new counter, initialised to 0.
*/
public Counter()
{
background = getImage(); // get image from class
value = 0;
target = 0;
updateImage();
}
/**
* Animate the display to count up (or down) to the current target value.
*/
public void act()
{
if (value < target) {
value++;
updateImage();
}
else if (value > target) {
value--;
updateImage();
}
}
/**
* Add a new score to the current counter value.
*/
public void add(int score)
{
target += score;
}
/**
* Return the current counter value.
*/
public int getValue()
{
return value;
}
/**
* Set a new counter value.
*/
public void setValue(int newValue)
{
target = newValue;
value = newValue;
updateImage();
}
/**
* Update the image on screen to show the current value.
*/
private void updateImage()
{
GreenfootImage image = new GreenfootImage(background);
GreenfootImage text = new GreenfootImage("" + value, 22, Color.BLACK, transparent);
image.drawImage(text, (image.getWidth()-text.getWidth())/2,
(image.getHeight()-text.getHeight())/2);
setImage(image);
}
}
