import Greenfoot.*;
import java.awt.Color;
 
public class GameOver extends Actor
{
    String msgTxt = "GAME OVER"
 
    public GameOver()
    {
        updateImage();
    }
 
    public GameOver(String txt)
    {
        msgTxt = txt;
        updateImage();
    }
 
    private void updateImage()
    {
        GreenfootImage image = new GreenfootImage(getWorld().getWidth(), getWorld().getHeight()); // or whatever size you want the object
        image.setColor(Color.cyan); // color of your choice
        image.fill();
        GreenfootImage txtImg = new GreenfootImage(msgTxt, 36, Color.black, new Color(0, 0, 0, 0)); // colors and font size of your choice
        image.drawImage(txtImg, (image.getWidth() - txtImg.getWidth()) / 2, (image.getHeight() - txtImg.getHeight) / 2);
        // whatever else you might want to do for the image
        setImage(image);
    }
}