I'm programming a version of Pong, and I have almost everything sorted out except the scoreboard. I'm not very good at doing scoreboards, so I compared a lot of different ones from different projects I have saved and tried to throw together one of my own. When I can get it to compile, it never displays the scoreboard properly, so I think I wrote it incorrectly, but my biggest problem right now is that it compiles with no syntax errors, but every time I try and add it to the world I get a nullPointerException, and I can't figure out why. Can anyne help me with this?? I'll post the source code for the ScoreBoard class below:
import greenfoot.*; // (World, Actor, GreenfootImage, Greenfoot and MouseInfo)
import java.awt.Font;
import java.awt.Color;
import java.lang.String;
/**
* Write a description of class ScoreBoard here.
*
* @author Emily Sullivan
* @version 1.0
*/
public class ScoreBoard extends Actor
{
private String text1 = "Player 1 : ";
private String text2 = "Player 2 : ";
private int score1;
private int score2;
private String player1score = String.valueOf(score1);
private String player2score = String.valueOf(score2);
// I have no clue if these last two variables are used correctly or if I need them or anything, I just tried it because I saw it somewhere and I needed to try something different, because what I was doing wasn't working.
/**
* Constructor for initial scoreboard.
*/
public ScoreBoard()
{
player1score = "0";
player2score = "0";
updateImage();
}
/**
* Constructor for ScoreBoard.
* @param: Name "Player 1", player 1's score, "player 2", player 2's score
*/
public ScoreBoard(String text1, String score1, String text2, String score2)
{
this.text1 = text1;
this.text2 = text2;
player1score = score1;
player2score = score2;
updateImage();
}
/**
* Act - do whatever the ScoreBoard wants to do. This method is called whenever
* the 'Act' or 'Run' button gets pressed in the environment.
*/
public void act()
{
updateImage();
}
/**
* Update the scoreboard to show the current score.
*/
private void updateImage()
{
GreenfootImage image = new GreenfootImage(550, 40);
Font font = new Font("Courier", Font.BOLD, 15);
image.setColor(Color.YELLOW);
image.setFont(font);
image.drawString(text1 + player1score, 0, 0);
image.drawString(text2 + player2score, getWorld().getWidth()/2 + 2, 0);
setImage(image);
}
}
