Thread: MeteorDodger Game JPanel Help (Timer?)

I made a game that creates meteors in random places at the top of the window, they fall, and you have to avoid them. The only problem is, it doesn't work right. There are no errors, it just doesn't work as intended. I think it has to to with the Timer and my inexperience with it, but I don't know.

import javax.swing.*;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Event;
import java.awt.Graphics; 
import java.awt.MouseInfo;
import java.awt.Point;
import java.awt.PointerInfo;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseMotionListener;
import java.awt.event.MouseMotionAdapter;
import java.util.ArrayList;
public class MeteorDodger {
	public static void main(String[] args) {
 
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createInterface(); 
            }
        });
    }
	private static void createInterface() {
        JFrame f = new JFrame("METEOR DODGER");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
        f.add(new MyPanel());
        f.setSize(500,500);
        f.setVisible(true);
    }
 
}
class MyPanel extends JPanel implements ActionListener {
 
    Meteor meteor = new Meteor();
    Player player = new Player();
    boolean gameOver = false;
    boolean isCollide = false;
    ArrayList<Meteor> meteorList = new ArrayList<Meteor>();
    int score = 0;
    int playerX = player.getMousePositionX();
	int playerY = player.getMousePositionY();
    Timer timer = new Timer(100, this);
 
    public MyPanel() {
 
        setBorder(BorderFactory.createLineBorder(Color.white));
        setBackground(Color.black);
 
    }
    //make meteor fall
    private void fall(Meteor m){
        final int FALL_DIST = 5;
            repaint(m.getX(), m.getY(), m.getRadius(), m.getRadius());
            m.setY(m.getY() + 5);
            repaint(m.getX(), m.getY() + FALL_DIST, m.getRadius(), m.getRadius());
    }
    //repaint the player if its moved
    private void repaintPlayer(){
 
    	if(playerX != player.getMousePositionX() && playerY != player.getMousePositionY()){
    		repaint(playerX, playerY, 20, 20);
    		repaint(player.getMousePositionX(), player.getMousePositionY(), 20, 20);
    	}
    }
    //creates a list of meteors and adds them to screen
    private void createMeteor(){
		meteorList.add(meteor);
		while(!(gameOver)){
			for (int i = 0; i < meteorList.size(); i++){
				meteorList.add(new Meteor());
				updateMeteorList();
			}
		}
 
	}
    //checks if meteor is off screen
    private void updateMeteorList(){
    	for (int i = 0; i < meteorList.size(); i++){
    		if((meteorList.get(i).isOutOfFrame())){
    			meteorList.remove(i);
    			//reset meteorList to check again(-1 accounts for increment of I after iteration is complete on next line)
    			i = -1;
    		}
    	}
    }
    //test if player touched a meteor
    private boolean collision(){
    	for (int i = 0; i < meteorList.size(); i++){
	    	int pX = player.getMousePositionX();
			int pY = player.getMousePositionY();
			int mX = meteorList.get(i).getX();
			int mY = meteorList.get(i).getY();
			if(pX > mX - 5 && pX < mX + 5){
				if(pY > mY - 5 && pY < mY + 5){
					isCollide = true;
					return isCollide;
				}
			}
			else{
				isCollide = false;
			}
 
    	}
    	return isCollide;
    }
 
    private boolean testGameOver(){
    	if(isCollide == true){
    		gameOver = true;
    		timer.stop();
    	}
    	return gameOver;
    }
 
    //increment score by 5
    private int scoreIncrement(){
    	if((gameOver)){
    		return score;
    	}
    	else{
    		return score+=5;
    	}
    }
 
    public Dimension getPreferredSize() {
        return new Dimension(250,200);
    }
    //Perform all actions ever 1/10 of a second
    @Override
    public void actionPerformed(ActionEvent e) {
		// TODO Auto-generated method stub
		createMeteor();
		for (int i = 0; i < meteorList.size(); i++){
			fall(meteorList.get(i));
		}
		repaintPlayer();
		scoreIncrement();
		collision();
		testGameOver();
		timer.restart();
 
	}  
 
    public void paintComponent(Graphics g) {
        super.paintComponent(g);       
        g.drawString("Score: " + score, 10 ,240);
        meteor.paintMeteor(g);
        player.paintPlayer(g);
        timer.start();
    }
 
 
}

import java.awt.Color;
import java.awt.Graphics;
import java.applet.*;
 
public class Meteor{
 
    private final int X = (int) (Math.random() * 250);
    private int y = 0;
    private int radius = 10;
 
    public int getX(){
        return X;
    }
 
    public void setY(int _y){
        this.y = _y;
    }
 
    public int getY(){
        return y;
    }
 
    public int getRadius(){
        return radius;
    }
    public boolean isOutOfFrame(){
    	if(getY() >= 250){
    		return true;
    	}
    	else{
    		return false;
    	}
    }
    public void paintMeteor(Graphics g){
        g.setColor(Color.white);
        g.fillOval(X, y, 2 * radius, 2 * radius); 
    }
}

import java.awt.Color;
import java.awt.Event;
import java.awt.Graphics;
import java.applet.Applet;
import java.awt.*;
import javax.swing.*;
 
public class Player {
	private int mousePositionX = getMousePositionX(), mousePositionY = getMousePositionY();
	public int getMousePositionX() {
		PointerInfo a = MouseInfo.getPointerInfo();
	    Point b = a.getLocation();
	    int x = (int) b.getX();
	    return x;
	}
 
	public int getMousePositionY() {
		PointerInfo a = MouseInfo.getPointerInfo();
	    Point b = a.getLocation();
	    int y = (int) b.getY();
	    return y;
	}
	//updates where the circle around your mouse is
	public void paintPlayer(Graphics g){
        g.setColor(Color.red);
        g.fillOval(getMousePositionX(), getMousePositionY(), 20, 20); 
    }
 
 
}

A single white ball appears at the top of the screen, and a red ball appears in the general area of where your mouse was when you ran the program. Nothing else happens.

I expect that several randomly placed(on the x axis) white balls will fall down, and the red ball follows your mouse. I expected that at least, i knew I would have to fix up a couple other glitches, but I knew Id cross that bridge once I got the majority of the program working. I also expect it to print "Score = 0" at the bottom of the screen but that isnt there either.

Just another thought. Could nothing happening also be the result of the repaint method call not working?

When I run your code it gets in a tight loop and I am unable to close the window.

Yeah me too. I dont know what thats about either. I have to force close it

Look at your logic for the createMeteor() method. It has loops that run forever.

Even when you fix that, i set it at 15 for example instead of meteorList.size(), and it still doesnt close or do anything.