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Why the character in my 2D game is not moving?

My program has 3 java files, namely Frame, Dude(which contains the character) and Board(which implements the actionListener). My program is not throwing any error and the images(background and character) are rendering good. But the character is not moving forward.
import javax.swing.*;
public class Frame {
public static void main(String[] args){
JFrame frame= new JFrame("2D Game");
frame.add(new Board());
frame.setVisible(true);
frame.setSize(1200, 600);
}
}
import java.awt.*;
import java.awt.event.KeyEvent;
import javax.swing.*;
public class Dude {
int x, dx, y;
Image still;
public Dude(){
ImageIcon i = new ImageIcon("/home/amitabh/Pictures/man1.jpg");
still= i.getImage();
x=10;
y=172;
}
public void move(){
x=x+dx;
}
public int getX(){
return x;
}
public int getY(){
return y;
}
public Image getImage(){
return still;
}
public void keyPressed(KeyEvent e){
int key= e.getKeyCode();
if(key== KeyEvent.VK_LEFT);
dx= -1;
if(key== KeyEvent.VK_RIGHT);
dx= 1;
}
public void keyReleased(KeyEvent e){
int key= e.getKeyCode();
if(key==KeyEvent.VK_LEFT);
dx=0;
if(key==KeyEvent.VK_RIGHT);
dx=0;
}
}
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Board extends JPanel implements ActionListener{
Image img;
Timer time;
Dude p;
public Board(){
p= new Dude();
addKeyListener(new AL());
setFocusable(true);
ImageIcon i= new ImageIcon("/home/amitabh/Pictures/game1.png");
img= i.getImage();
time= new Timer(5,this);
time.start();
}
#Override
public void actionPerformed(ActionEvent e) {
p.move();
repaint();
}
public void paint(Graphics g){
super.paint(g);
Graphics2D g2d= (Graphics2D)g;
g2d.drawImage(img, 0,0, null);
g2d.drawImage(p.getImage(), p.getX(), p.getY(), null);
}
public class AL extends KeyAdapter{
public void keyReleased(KeyEvent e){
p.keyReleased(e);
}
public void KeyPressed(KeyEvent e){
p.keyPressed(e);
}
}
}

Start by talking a very close look at:
if (key == KeyEvent.VK_LEFT);
Does that look funny to you?
if (key == KeyEvent.VK_LEFT); // <--- What's the ; doing here?
Change it to be more like...
if (key == KeyEvent.VK_LEFT) {
dx = 0;
}
And, yes, this is why you're encouraged to use { ... }
Next, take a closer look at...
public void KeyPressed(KeyEvent e) {
See anything wrong there? Why does it start with an uppercase K, that's not the correct method signature
Change to something more like...
#Override
public void keyReleased(KeyEvent e) {
p.keyReleased(e);
}
#Override
public void keyPressed(KeyEvent e) {
p.keyPressed(e);
}
Yes, this is why you're encouraged to use #Override ;)
And finally change your paint method to paintComponent
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
You are encouraged to override paintComponent when performing custom painting, it tends to cause less issues
I'd also encorage you to have a look at the Key Bindings API and favour it over KeyListener as it provides better control of the focus level required to trigger the key events
I'd also encourage your to override getPreferredSize of the Board and return your preferred size from there, rather then setting the frame's size. The frame size includes the frame's decorations, so you content is smaller then the frame size

I cannot draw objects and have them move on the screen

I can draw static things to the screen, but I want to make them move with user key input. I don't know what to do, I've been searching and searching and haven't come up with an answer yet. Please help!
package com.Game.game;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Game extends JFrame
{
final static int width = 500;
final static int height = 500;
public int x = 250;
public int y = 250;
public int changeX = 10;
public int changeY = 10;
public static void main(String[] args)
{
new Game();
}
public Game()
{
KeyListener listener = new KeyListening();
addKeyListener(listener);
setFocusable(true);
DrawingStuff drawingstuff = new DrawingStuff();
add(drawingstuff);
setSize(width, height);
setLocationRelativeTo(null);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}
public class DrawingStuff extends JPanel
{
public void paintComponent(Graphics g)
{
super.paintComponent(g);
g.drawString("Hey there!", 300, 300);
g.setColor(Color.RED);
g.fillRect(x, y, 50, 50);
}
}
public class KeyListening implements KeyListener
{
DrawingStuff drawingstuff = new DrawingStuff();
#Override
public void keyPressed(KeyEvent e)
{
if(e.getKeyCode() == KeyEvent.VK_UP)
{
y = y + changeY;
System.out.println("Hey");
drawingstuff.repaint();
}
}
#Override
public void keyReleased(KeyEvent e)
{
}
#Override
public void keyTyped(KeyEvent e)
{
}
}
public void update()
{
}
}
EDIT: Fixed it. I took away the key listener stuff in the constructor method, added a command to focus on "drawingstuff" in the constructor method, and, most importantly, added this bit of code to the end of the constructor method:
while(true)
{
drawingstuff.repaint();
}

The problem is that your KeyListening object has a reference to a different DrawingStuff object than the one you added to your UI inside the Game constructor.
public class KeyListening implements KeyListener
{
DrawingStuff drawingstuff = new DrawingStuff();
...
You should pass a DrawingStuff reference to the KeyListening instance so that it can tell the right object to repaint itself.

I need a little help implementing player movement on java grid

I need a little help with java, I am new to the language hence I have no idea on how to implement such.
I have already made a basic 15;40 grid JLabel Image, thanks to this site as well, what I need help with is about how to make a player(Supposed to be an Image, also shown on the grid) move around using either WASD(I don't know if Ascii-approach works on java) or Arrow Keys.
Here's my code for the Grid
public class GUI {
static Scanner cns = new Scanner(System.in);
JFrame frame = new JFrame();
ImageIcon ImageIcon = new ImageIcon("Grass.png");
JLabel[][] grid;
public GUI(int width, int length) {
Container pane = frame.getContentPane();
frame.setLayout(new GridLayout(width,length));
grid = new JLabel[width][length];
for(int y = 0; y < length; y++) {
for(int x = 0; x < width; x++) {
grid[x][y] = new JLabel();
grid[x][y].setBorder(BorderFactory.createLineBorder(Color.black));
grid[x][y].setBorder(BorderFactory.createEmptyBorder());
}
}
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
for(int y = 0; y < length; y++) {
for(int x = 0; x < width; x++) {
pane.add(grid[x][y]= new JLabel(new ImageIcon("Grass.png")));
grid[x][y].setBorder(BorderFactory.createLineBorder(Color.black));
grid[x][y].setBorder(BorderFactory.createEmptyBorder());
frame.add(grid[x][y]);
}
}
}
public static void main(String[] args) {
new GUI(15, 40);
}
}

Couple of suggestions here:
1 - Make GUI extend JFrame and implement KeyListener.
You have to override KeyListener methods (keyPressed, keyReleased, and keyTyped) and you should override repaint() from JFrame.
The repaint method should call super.repaint() at the end to update frames.
2 - Have the fields of GUI store data about the things that need to be drawn.
You probably should store the grid, or what's in the grid as fields.
3 - The constructor should initialize, not render.
Rendering should be done in repaint(). The constructor should do something like this:
super();
JPanel frame = new JPanel();
add(frame);
pack();
addKeyListener(this);
repaint();
This answer is kinda unfinished but I'll look more into it and update this. Particularly, the JPanel is an element in the JFrame.
UPDATE: Here is a small working example. Use WASD to move the rectangle around the screen.
This is the JFrame.
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JFrame;
public class MyJFrame extends JFrame implements KeyListener {
private MyJPanel frame;
public MyJFrame() {
super();
frame = new MyJPanel();
add(frame);
pack();
addKeyListener(this);
repaint();
}
public static void main(String[] args) {
MyJFrame window = new MyJFrame();
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setVisible(true);
window.setTitle("Test");
}
#Override
public void repaint() {
super.repaint();
}
#Override
public void keyPressed(KeyEvent e) {
frame.keyPressed(e);
repaint();
}
#Override
public void keyTyped(KeyEvent e) { }
#Override
public void keyReleased(KeyEvent e) { }
}
This is the JPanel.
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.KeyEvent;
import javax.swing.JPanel;
public class MyJPanel extends JPanel {
private int x = 0;
private int y = 0;
public MyJPanel() {
setPreferredSize(new Dimension(200,200));
}
#Override
public void update(Graphics g) {
paint(g);
}
#Override
public void paint(Graphics g) {
g.setColor(Color.red);
g.drawRect(x,y,20,20);
}
public void keyPressed(KeyEvent e) {
int k = e.getKeyCode();
switch (k) {
case KeyEvent.VK_D:
x++;
break;
case KeyEvent.VK_A:
x--;
break;
case KeyEvent.VK_W:
y--;
break;
case KeyEvent.VK_S:
y++;
break;
}
}
}
Good luck!

Sprite Movement in Java

I started learning java as a hobby a little while back because I wanted to make a little game. I learned the basics of java, and I decided that I would try to tackle game-dev. My JFrame and all is fine and I technically have no bugs, but my little rectangle guy won't move around the screen. Here's my code:
package main;
import java.awt.Color;
import java.awt.Container;
import java.awt.Graphics;
import java.awt.Rectangle;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JFrame;
public class Race extends JFrame {
public int speed=5;
public int up=1;
public int left=2;
public int down=3;
public int right=4;
public int direction=0;
Rectangle p1 = new Rectangle (500,400,20,40);
public Race()
{
super("Race");
setSize(1000,800);
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container cont=getContentPane();
cont.setBackground(Color.orange);
setResizable(false);
}
public void paint(Graphics g)
{
super.paint(g);
g.setColor(Color.red);
g.fillRect(p1.x, p1.y, p1.width, p1.height);
}
public class Move extends Thread implements KeyListener
{
public void run()
{
addKeyListener(this);
while(true)
{
try
{
repaint();
if(direction==up)
{
p1.y-=(int)speed;
}
if(direction==down)
{
p1.y+=(int)speed;
}
if(direction==right)
{
p1.x+=(int)speed;
}
if(direction==left)
{
p1.x-=(int)speed;
}
Thread.sleep(75);
}
catch (Exception e)
{
break;
}
}
}
#Override
public void keyPressed(KeyEvent event) {
// TODO Auto-generated method stub
}
#Override
public void keyReleased(KeyEvent event) {
// TODO Auto-generated method stub
}
#Override
public void keyTyped(KeyEvent event) {
// TODO Auto-generated method stub
if(event.getKeyChar()=='w')
{
direction = up;
}
if(event.getKeyChar()=='d')
{
direction = left;
}
if(event.getKeyChar()=='s')
{
direction = down;
}
if(event.getKeyChar()=='a')
{
direction = left;
}
}
}
public static void main(String[] args)
{
new Race();
}
}

There are a couple of problems:
You aren't creating a Move instance so nothing is listening to keys.
I don't think you even need a Move class that runs in a background thread. Take the KeyListener logic and put it in your Race class, then "enable" the keyListener by calling addKeyListener(this); so it starts listening to key presses.
Race extends JFrame implements KeyListener{
Race(){
...
addKeyListener(this);
}
#Override
public void keyTyped(KeyEvent event) {
if(event.getKeyChar()=='w')
{
direction = up;
}
if(event.getKeyChar()=='d')
{
direction = left;
}
if(event.getKeyChar()=='s')
{
direction = down;
}
if(event.getKeyChar()=='a')
{
direction = left;
}
repaint();
}
Also see this SO question : Unresponsive KeyListener for JFrame for more help.

If you call the Move class like this in the Race class:
public Move move;
and then call it under you Race constructor:
move = new Move();
in you Move class you make a constructor like this:
public Move()
{
run();
}
This should make it move :)
And for heads up, you need to change the keypress d to go to the right instead of left.

JButton isn't in the right place when a BufferedImage is used in it's container

I'm trying to create a simple game using AWT but I want to have some JButtons aswell to exit/reset the game. The problem is, I want the BufferedImage to be drawn inside the visible frame like so in my container I have this at the end:
g.drawImage(bf,getParent().getInsets().left,getParent().getInsets().top,null);
My problem is, when I add a JButton to that frame, it only detects rollover in space that doesn't take into account the offsetting, but is drawn in a space that does. This is the relevant code (con is the container).
private void addButtons()
{
reset = new JButton("reset");
reset.setBounds(180,460, 75,30);
reset.addActionListener( this );
con.add(reset);
exit = new JButton("exit");
exit.setBounds(290,460, 60,30);
exit.addActionListener( this );
con.add(exit);
con.repaint();
}
The paint method in the Container
public void paint(Graphics g)
{
bf = new BufferedImage(this.getWidth(), this.getHeight(), BufferedImage.TYPE_INT_RGB);
Graphics b = bf.getGraphics();
b.setColor(Color.GRAY);
b.fillRect(0, 0, this.getWidth(), this.getHeight());
b.setColor(Color.BLACK);
b.drawRect(0,0,420,420);
super.paint(b);
g.drawImage(bf,getParent().getInsets().left,getParent().getInsets().top,null);
}
How can I make the button be drawn and detected in the same spot?
here is a screenshot of the problem
As requested:
import java.awt.*;
import javax.swing.*;
import java.util.*;
import java.awt.image.*;
import java.awt.event.*;
import java.awt.Color;
public class Draw implements ActionListener{
private SnakeFrame frame;
private SnakeCon con;
JButton reset, exit;
private boolean res;
public Draw()
{
frame = new SnakeFrame("Snake");
frame.setResizable(false);
frame.setLayout(null);
frame.setSize(600,600);
frame.setVisible(true);
con = new SnakeCon();
con.setBounds(0,0,600,600);
frame.add(con);
}
private void addButtons()
{
reset = new JButton("reset");
reset.setBounds(180,460, 75,30);
reset.addActionListener( this );
con.add(reset);
exit = new JButton("exit");
exit.setBounds(290,460, 60,30);
exit.addActionListener( this );
con.add(exit);
con.repaint();
}
public void run()
{
addButtons();
res = false;
boolean dead = false;
while(!dead)
{
if( (res) )
dead = true;
if (!dead)
{
try{
Thread.sleep(100);
}
catch (Exception e)
{}
frame.repaint();
}
}
con.removeAll();
}
public void actionPerformed(ActionEvent e)
{
if (e.getSource() == reset)
res = true;
else if (e.getSource() == exit)
System.exit(0);
}
}
--
import java.awt.*;
import javax.swing.*;
import java.util.*;
import java.awt.image.*;
import java.awt.event.*;
import java.awt.Color;
public class SnakeCon extends Container{
private BufferedImage bf;
public SnakeCon()
{
super();
setBounds(0,0,600,600);
}
public void paint(Graphics g)
{
bf = new BufferedImage(this.getWidth(), this.getHeight(), BufferedImage.TYPE_INT_RGB);
Graphics b = bf.getGraphics();
b.setColor(Color.GRAY);
b.fillRect(0, 0, this.getWidth(), this.getHeight());
b.setColor(Color.BLACK);
b.drawRect(0,0,420,420);
super.paint(b);
g.drawImage(bf,getParent().getInsets().left,getParent().getInsets().top,null);
}
public void update(Graphics g)
{
paint(g);
}
}
--
import java.awt.*;
import javax.swing.*;
import java.util.*;
import java.awt.image.*;
import java.awt.event.*;
import java.awt.Color;
public class SnakeFrame extends Frame implements WindowListener{
private BufferedImage bf;
public SnakeFrame(String s)
{
super(s);
addWindowListener( this );
}
public void paint(Graphics g)
{
bf = new BufferedImage(this.getWidth(), this.getHeight(), BufferedImage.TYPE_INT_RGB);
Graphics b = bf.getGraphics();
super.paint(b);
g.drawImage(bf,0,0,null);
}
public void update(Graphics g)
{
paint(g);
}
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
public void windowClosed(WindowEvent e) { }
public void windowOpened(WindowEvent e) { }
public void windowIconified(WindowEvent e) { }
public void windowDeiconified(WindowEvent e) { }
public void windowActivated(WindowEvent e) { }
public void windowDeactivated(WindowEvent e) { }
}
--
public class Main {
public static void main(String[] args)
{
boolean never = false;
Draw d = new Draw();
while(!never)
{
d.run();
}
System.exit(0);
}
}

Im not sure exactly what is wrong/what you want (why do you have a loop to constantly drawing buttons and invoking removeAll()? etc but i cant shake the feeling it might be implemented in a more readable/efficient way)...
But here are some suggestions that can only help your code get better:
Dont use null/Absolute Layout choose an appropriate LayoutManager.
Do not override JFrame paint(..), rather add JPanel to JFrame and override paintComponent(Graphics g) of JPanel and do drawing there.(Do not forget to have super.paintComponent(..) as 1st call in overriden paintComponent method. See here for more: Performing Custom Painting
Do not set JFrame visible before adding all components to JFrame
Always create and manipulate Swing components on Event Dispatch Thread like so:
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
//create Swing components
}
});
Do not do long running tasks on Event Dispatch Thread rather use Swing Timer/Swing Worker
Do not call setSize(..) on JFrame rather override getPreferredSize() of JPanel and return Dimensions which fit all components (see here for reasoning), than call pack() on JFrame before setting it visible
Dont extend JFrame unnecessarily or Container!
Adding WindowListener for detecting JFrame exit is not worth the lines rather use:
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
to exit Swing application when X is pressed.