This is the thread to make the numbers show up:
class CoOrdCounter extends Thread{
public void run(){
try{
while(true){
Thread.sleep(500);
printX = cow.x;
printY = cow.y;
}
}catch(Exception e){}
}
}
//Of course I also have CoOrdCounter co = new CoOrdCounter; co.start();
And then...
g.drawString("Co-ords: ("+printX+","+printY+")",50,100);
It always displays (0,0)
, probably because of int printX = 0, printY = 0;
. So that means the variables were NOT changed at all... Why? And how should I make this work...?
[PLEASE] I know I shouldn't use paint() but I'm beginner-intermediate so...
[EDIT] And now that MadProgrammer mentions it, I do get an EventDispatchThread error.
[EDIT 2] I understand to use a Timer
but @MadProgrammer
how do I get cow.x
and cow.y
by using your code snippet?
[EDIT 3] If you type the key p
the KeyListener
will start the instance of the Thread
Slider
, thread
.
[UPDATE CLASS 2 (the real thing)]
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.util.*;
import java.io.*;
import java.net.*;
@SuppressWarnings({"serial","rawtypes","unchecked"})
public class CowbenderI extends JFrame implements MouseListener, KeyListener{
CoOrdCounter co;
Counter cnt;
Icon icon = new ImageIcon("resources/img/cow.png");
int focusX = 0, focusY = 0, counter = 0;
ArrayList lines = new ArrayList();
Point2D.Double start;
final Color BROWN = new Color(156,93,82);
Slider thread;
Rectangle cow = null;
boolean drawGuy = false, useFinal = false, checkedForWin = false, alive = true;
int finalTime = 0;
int printX = 0, printY = 0;
public CowbenderI(){
super("Cowbender I - \"Slope Run\"");
setSize(700,700);
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
addMouseListener(this);
addKeyListener(this);
cnt = new Counter();
cnt.go = false;
cnt.start();
co = new CoOrdCounter();
co.go = false;
co.start();
}
public void paint(Graphics g){
super.paint(g);
try{
g.setColor(Color.WHITE);
g.fillRect(-2000, -2000, 5000, 5000);
URL url = this.getClass().getResource("resources/img/world/slope.png");
Image bckgrnd = Toolkit.getDefaultToolkit().getImage(url);
g.drawImage(bckgrnd,0,0,this);
}catch(Exception e){}
g.setColor(BROWN);
for(int i = 0; i < lines.size(); i++){
Line2D.Double temp = (Line2D.Double) lines.get(i);
int x1 = Integer.parseInt(""+Math.round(temp.getX1()));
int x2 = Integer.parseInt(""+Math.round(temp.getX2()));
int y1 = Integer.parseInt(""+Math.round(temp.getY1()));
int y2 = Integer.parseInt(""+Math.round(temp.getY2()));
g.drawLine(x1-focusX,y1-focusY,x2-focusX,y2-focusY);
}
if(drawGuy){
try{
g.setFont(new Font("Arial",Font.BOLD,16));
if(useFinal == false) g.drawString("Current Time: "+counter,50,50);
else g.drawString("Current Time: "+finalTime,50,50);
g.drawString("Co-ords: ("+printX+","+printY+")",50,100);
if(alive == true){
URL url = this.getClass().getResource("resources/img/world/char.png");
Image image = Toolkit.getDefaultToolkit().getImage(url);
g.drawImage(image, cow.x-focusX, cow.y-focusY, this);
}
else{
URL url = this.getClass().getResource("resources/img/world/deadchar.png");
Image image = Toolkit.getDefaultToolkit().getImage(url);
g.drawImage(image, cow.x-focusX, cow.y-focusY, this);
if(checkedForWin == false){
finalTime = counter;
useFinal = true;
checkWin();
}
}
} catch(Exception exc){}
focusX = cow.x-100;
focusY = cow.y-100;
}
}
public void checkWin(){
if(finalTime >= 45){
JOptionPane.showMessageDialog(null,"You won!\nThe farmer got tired and ran back!","Cowbender I - The Slope",JOptionPane.INFORMATION_MESSAGE,icon);
System.exit(0);
}
}
public void mouseClicked(MouseEvent e){}
public void mouseEntered(MouseEvent e){}
public void mouseExited(MouseEvent e){}
public void mousePressed(MouseEvent e){
start = new Point2D.Double(e.getX()+focusX,e.getY()+focusY);
}
public void mouseReleased(MouseEvent e){
Point2D.Double end = new Point2D.Double(e.getX()+focusX,e.getY()+focusY);
lines.add(new Line2D.Double(start,end));
repaint();
}
public void keyPressed(KeyEvent e){}
public void keyReleased(KeyEvent e){}
public void keyTyped(KeyEvent e){
if(e.getKeyChar()=='w'||e.getKeyChar()=='W'){
focusY-=100;
repaint();
}
if(e.getKeyChar()=='a'||e.getKeyChar()=='A'){
focusX-=100;
repaint();
}
if(e.getKeyChar()=='s'||e.getKeyChar()=='S'){
focusY+=100;
repaint();
}
if(e.getKeyChar()=='d'||e.getKeyChar()=='D'){
focusX+=100;
repaint();
}
if(e.getKeyChar()=='p'||e.getKeyChar()=='P'){
alive = true;
counter = 0;
cnt.go = true;
co.go = true;
useFinal = false;
thread = new Slider();
thread.start();
thread.action(true);
}
if(e.getKeyChar()=='z'||e.getKeyChar()=='Z'){
lines.remove(lines.size()-1);
repaint();
}
if(e.getKeyChar()=='x'||e.getKeyChar()=='X'){
int response = milkSwing.confirmBox(null, "Do you really want to remove all of your summoned earth?", "Cowbender - The Slope", JOptionPane.YES_NO_OPTION);
if(response == JOptionPane.YES_OPTION) lines.clear();
repaint();
}
if(e.getKeyChar()=='q'||e.getKeyChar()=='Q'){
System.exit(0);
}
}
class CoOrdCounter extends Thread{
public boolean go = true;
public void run(){
try{
while(true){
if(go){
Thread.sleep(500);
printX = cow.x;
printY = cow.y;
repaint();
}
}
}catch(Exception e){}
}
}
class Counter extends Thread{
public boolean go = true;
public void run(){
try{
while(true){
if(go){
Thread.sleep(1000);
counter++;
}
}
} catch(Exception e){}
}
}
private class Slider extends Thread{
double velocity, gravity;
boolean go = false;
public void run(){
if(go){
initGuy();
velocity = 0;
gravity = 1;
}
while(go){
try{
Line2D.Double lineTaken = null;
boolean onLine = false;
int firstOnLine = -1;
for(int i = lines.size()-1; i>=0; i--){
Line2D.Double temp = (Line2D.Double) lines.get(i);
if(temp.intersects(cow.x,cow.y,50,50)){
lineTaken = temp;
onLine = true;
if(firstOnLine!=i){
firstOnLine = i;
gravity = 0;
}
break;
}
}
if(onLine){
double grav = (lineTaken.y2-lineTaken.y1)/50;
double vlct = (lineTaken.x2-lineTaken.x1)/100;
if(velocity<5)velocity+=vlct;
if(gravity<2.5)gravity+=grav;
}
else{
gravity+=.2;
}
cow.x+=velocity;
cow.y+=gravity;
if(cow.x > 10000) alive = false;
Thread.sleep(75);
repaint();
}catch(Exception e){break;}
}
}
public void action(boolean b){
go = b;
}
public void initGuy(){
Line2D.Double firstLine = (Line2D.Double) lines.get(0);
int x = Integer.parseInt(""+Math.round(firstLine.x1));
int y = Integer.parseInt(""+Math.round(firstLine.y1));
cow = new Rectangle(x+90,y-60,50,50);
drawGuy = true;
}
}
/**
* @param args
*/
public static void main(String[] args) {
CowbenderI g = new CowbenderI();
}
}<br />
[EDIT 4] @MadProgrammer not working:
You need to tell Swing that you want to update the UI. In you're case that's going to present issues as it's possible to violate the contract with the Event Dispatching Thread (that you should never update the UI from any thread other then the Event Dispatching Thread)
The example I've done below uses a simple javax.swing.Timer
, which overcomes this issue
public class PrintNumbers {
public static void main(String[] args) {
new PrintNumbers();
}
public PrintNumbers() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new PrintPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class PrintPane extends JPanel {
private int printX;
private int printY;
public PrintPane() {
Timer timer = new Timer(500, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
printX = (int) Math.round(Math.random() * 1000);
printY = (int) Math.round(Math.random() * 1000);
repaint();
}
});
timer.setRepeats(true);
timer.setCoalesce(true);
timer.start();
}
@Override
public Dimension getPreferredSize() {
return new Dimension(100, 100);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
int width = getWidth() - 1;
int height = getHeight() - 1;
FontMetrics fm = g.getFontMetrics();
String text = printX + "x" + printY;
int x = (width - fm.stringWidth(text)) / 2;
int y = ((height - fm.getHeight()) / 2) + fm.getAscent();
g.drawString(text, x, y);
}
}
}
UPDATED
From the example code.
First, the list of things that are wrong with your sample code...
JFrame
or override the paint
method. You would better off extending from a JPanel
and overriding paintComponent
. Firstly this will provide you with automatic double buffering, secondly, it will provide you with the flexible deployment options (add the panel to a JFrame
or JApplet
) go
is false) is wasting CPU as these threads still need to be scheduled to run. Have a read through Concurrency , in particular Synchronization and locks KeyListener
. It has better focus control (the component doesn't have to have focus in order to trigger the actions) and produces pluggable and reusable code. catch (Exception e) {}
isn't going to tell you anything if something goes wrong. At the very least you should be logging the exception. As to your problem..
Start by making CoOrdCounter#go
, Counter#go
, Slider#go
and Cow
volatile .
I got away with CoOrdCounter#go
and was able to see the results printed to the console correctly (you graphics didn't work on my machine for reasons stated above)
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