Thread: Mutiple classfile, JPanel nothing shows up

I had 2 .java files and I decided it was too much stuff in two file .java so I made more class but now nothing is showing up :\


myFrame.java

import javax.swing.*;
import java.awt.event.*;
 
 
public class myFrame extends JPanel implements ActionListener,KeyListener {
	private static final long serialVersionUID = 1L;
 
	Timer t = new Timer(5, this);
 
	public myFrame() {
		t.start();
		addKeyListener(this);
		setVisible(true);
		setFocusable(true);
		setFocusTraversalKeysEnabled(false);		
	}
 
 
	public void actionPerformed(ActionEvent e) {
		// TODO Auto-generated method stub
 
	}
 
 
	@Override
	public void keyPressed(KeyEvent e) {
		// TODO Auto-generated method stub
 
	}
 
 
	@Override
	public void keyReleased(KeyEvent e) {
		// TODO Auto-generated method stub
 
	}
 
 
	@Override
	public void keyTyped(KeyEvent e) {
		// TODO Auto-generated method stub
 
	}	
}

arkanoidGame.java

import javax.swing.JFrame;
 
public class arkanoidGame {
 
 
	public static void main(String[] args) {
		JFrame frame = new JFrame();
		myFrame s = new myFrame();
		Ball b = new Ball();
		pad p = new pad();
		frame.add(p);
		frame.add(b);
		frame.add(s);
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.setSize(800,600);
		frame.setVisible(true);
	}	
}

ball.java

import javax.swing.*;
import java.awt.*;
 
 
public class Ball extends JPanel implements Runnable{
 
	private static final long serialVersionUID = 1L;
	int ballX = 60;
	int ballY = 60;
	int ballWH = 25;
 
 
	public void init() { 
		setBackground(Color.BLUE);
	}
 
	public void start() {
		// define a new thread 
		Thread th = new Thread (this); 
		// start this thread 
		th.start (); 
		} 
 
 
	public void stop() { } 
 
	public void destroy() { } 
 
 
 
	public void paint (Graphics g) {
		super.paint(g);
		g.setColor(Color.blue);
		g.fillOval(ballX-ballWH,ballY-ballWH,2*ballWH,2*ballWH);
	} 
 
 
 
	public void run() {
		// lower ThreadPriority 
		Thread.currentThread().setPriority(Thread.MIN_PRIORITY); 
 
		// run a long while (true) this means in our case "always" 
		while (true) 
		{ 
			ballX++;
			ballY++;
			repaint(); 
 
		try 
		{
		// Stop thread for 20 milliseconds 
		Thread.sleep (20); 
		} 
		catch (InterruptedException ex) 
		{
		// do nothing 
		} 
 
		// set ThreadPriority to maximum value 
		Thread.currentThread().setPriority(Thread.MAX_PRIORITY); 
 
		}
 
	}
}

pad.java

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.geom.Rectangle2D;
import javax.swing.JPanel;
import javax.swing.Timer;
 
 
public class pad extends JPanel implements KeyListener, ActionListener {
 
	Timer t = new Timer(5, this);
 
	double rectX = 15;
	double rectY = 540;
	int rectWidth = 80;
	int rectHeight = 20;
	double rectVeloX = 0.0;
	double rectVeloY = 0.0;
 
	private static final long serialVersionUID = 1L;
 
	public void paint(Graphics draw2D){		
 
		super.paint(draw2D);
		Graphics2D draw = (Graphics2D) draw2D;
		draw.setColor(Color.red);
		draw.fill(new Rectangle2D.Double(rectX,rectY, rectWidth, rectHeight));
		draw.getClipBounds(); 
 
	}
 
	public void actionPerformed (ActionEvent e) {
	   	repaint();
		rectX += rectVeloX;
		rectY += rectVeloY;		
	}
	public void keyPressed(KeyEvent e) {
		int key = e.getKeyCode();
 
		   if (key == KeyEvent.VK_RIGHT ) {
			   if ((rectX+rectWidth) >= 800)
			   {
				   rectVeloX = 0;
				   rectX = 800-rectWidth;
			   }
			   else {
			   rectVeloX = 1.5;
			   rectVeloY = 0;
			   }
 
	    }  if (key == KeyEvent.VK_LEFT ) {
	    		if (rectX <= 0) 
	    		{
	    			rectVeloX = 0;
	    			rectX = 0;
	    		}
	    		else {
				   rectVeloX = -1.5;
				   rectVeloY = 0;
	    		}
	    }
 
	}
 
	public void keyReleased(KeyEvent e) {
		int key = e.getKeyCode();
 
			if (key == KeyEvent.VK_RIGHT) {
				rectVeloX = 0;
				rectVeloY = 0;
 
			}
 
			if (key == KeyEvent.VK_LEFT) {
				rectVeloX = 0;
				rectVeloY = 0;
			}
	}
 
	public void keyTyped(KeyEvent e) {}		
 
}

No errors... The windows opens but nothing in it.

Originally Posted by Norm

Use paintCompoment not PaintComponent

Sorry it was a typo... I used paintComponent and the rectangle let a footprints on his side when I moved it around

I tryed the drawLine method and nothing appears on the screen.

I don't use a layout manager. I guess that my problem... in my arkanoidGame.java I do :

JFrame frame = new JFrame();

frame.setBounds(0,0,800,600); does it set the bounds?

Nothing prints out

Originally Posted by Norm

If you print the bounds of the components from their paint()

Just to be sure how do I print out those bounds? Inside the paintComponent method?

public void paintComponent(Graphics draw2D) {
............
............
System.out.println(..........);
} ???

Originally Posted by Norm

What is the MyFrame class used for? It does not have an override for the paint() method but it extends JPanel so I assume it should be showing something.

myFrame is the frame.... extend JPanels to use

addKeyListener(this);
setVisible(true);
setFocusable(true);
setFocusTraversalKeysEnabled(false);

Originally Posted by Norm

So it does not display anything on the screen?

Right nothing,

I added : System.out.println("myFrame bounds = " + getBounds());
on the public myFrame constructor and I got :
myFrame bounds = java.awt.Rectangle[x=0,y=0,width=800,height=600]

none of all other class printed anything

Originally Posted by Norm

Add a paintComponent() method with that println of the bounds to the MyFrame class and see if it is called and prints anything.

myFrame bounds = java.awt.Rectangle[x=0,y=0,width=792,height=573] It prints it twice.

Originally Posted by Norm

Did you look at the layout manager part?
If you give several components to the layout manager and tell it to put them all in the same place, only the last one added will be shown. The ones added earlier will be overlain/replaced by the later ones.

Your code uses the default so all the components go to the same place and the last one added is the one that is left.

Change the order that the components are added to see if the printout changes.

JFrame frame = new JFrame();
myFrame s = new myFrame();
ball b = new ball();
pad p = new pad();
frame.add(p);
frame.add(b);
frame.add(s);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOS E);
frame.setSize(800,600);

So I guess that only the frame.add(s); works in there right?...

So I overrides the first 2?

I changed it for :

public static void main(String[] args) {
JFrame frame = new JFrame();
myFrame s = new myFrame();
ball b = new ball();
pad p = new pad();
frame.add(s);
frame.add(p);
frame.add(b);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOS E);
frame.setSize(800,600);

and the ball appeared... but the pad didn't since the ball override the pad....

public class arkanoidGame {

public static void main(String[] args) {
JFrame frame = new JFrame();
JPanel panel = new JPanel();
myFrame s = new myFrame();
ball b = new ball();
pad p = new pad();
panel.add(s);
panel.add(p);
panel.add(b);
frame.add(panel);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOS E);
frame.setSize(800,600);
frame.setVisible(true);
}
}

I Added a panel and the bounds changed to :
myFrame bounds = java.awt.Rectangle[x=376,y=5,width=10,height=10] Why?

Originally Posted by Norm

One of the magic events caused by a layout manager. The JPanel has a different default layout manager from the JFrame.

You need to figure out what layout you want to use for those 3 components.
Have you seen the tutorial:
A Visual Guide to Layout Managers (The Java™ Tutorials > Creating a GUI With JFC/Swing > Laying Out Components Within a Container)

Well the ball as to go anywhere....

The pad can stay at the bottom

And the bricks at the top...

3 Different Layout?

Ok!, I got rid of my myFrame class I think it was pretty much useless so now I got my arkanoidGame ,pad and ball Class

I tryed the System.out.println in the addComponentsToPane and it gives me
myFrame bounds = java.awt.Rectangle[x=0,y=0,width=0,height=0]

So I don't really know why It's 0.......I did set the size and bounds in createAndShowGui

import java.awt.*;
import javax.swing.*;
 
 
public class arkanoidGame extends JFrame {
	FlowLayout layout = new FlowLayout();
 
	private static final long serialVersionUID = 1L;
 
 
	public arkanoidGame(String name) {	
		super(name);
 
	}
	public void addComponentsToPane(final Container pane) {
 
		final JPanel panel = new JPanel();		
		panel.setLayout(layout);
		panel.add(new ball());
		panel.add(new pad());	
		System.out.println("myFrame bounds = " + getBounds());
	}
 
	private static void createAndShowGui() {
		arkanoidGame frame = new arkanoidGame("Arkanoid Game");
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.addComponentsToPane(frame.getContentPane());				
		frame.pack();
		frame.setSize(800,600);
		frame.setBounds(0,0,800,600);	
		frame.setFocusable(true);
		frame.setFocusTraversalKeysEnabled(false);
		frame.setVisible(true);		
	}
 
	public static void main(String[] args) {
		try {
            //UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
            UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
        } catch (UnsupportedLookAndFeelException ex) {
            ex.printStackTrace();
        } catch (IllegalAccessException ex) {
            ex.printStackTrace();
        } catch (InstantiationException ex) {
            ex.printStackTrace();
        } catch (ClassNotFoundException ex) {
            ex.printStackTrace();
        }
		  UIManager.put("swing.boldMetal", Boolean.FALSE);
 
	        javax.swing.SwingUtilities.invokeLater(new Runnable(){
	            public void run() {
	                createAndShowGui();
	            }	
 
	        });
	}
}