Thread: paintComponent error

i am painting a rect in player.java and i want to print in main.java class.
in main i am using paintComponent but in player class iam using paint method.

my 1st question is that shoud i use paintComponent in both classes? or is it right that way i have it.

my 2nd question is that. i have a error:
The method paint(Graphics, main) in the type player is not applicable for the arguments (Graphics, main.Display)

error on line: player_class.paint(g, this)

note if i send 'this' to different class than i get error. but if i only send 'g' than it works fine.
main.java

public class main extends JApplet
{   
    Timer timer;
    Display display_class;
    player player_class;
 
 
    /*** init method ***/
    public void init()
    {
        setSize(800, 400);
        display_class = new Display(); 
        setContentPane(display_class);  
    }/*** end of init method ***/
 
 
 
    /*** stat method ***/
    public void start()
    {   player_class = new player();
        timer = new Timer(30, this);  
        timer.start();               
    }/*** end of start method ***/
 
 
 
    /*** game loop ***/
    public void actionPerformed(ActionEvent e)
    {   
        repaint();
    }/*** end of run method ***/
 
 
 
    /*** paint method ***/ 
    public class Display extends JPanel
    {
        public void paintComponent(Graphics g)
        {   
            super.paintComponent(g);     
 
            player_class.paint(g, this);   
        }/** end of paint component method ***/
     }/*** end of display class ***/
}/*** end of main class ***/

player.java

public class player
{
    /*** PLAYER VARIABLES ***/
    private int x = 10;
    private int y = 200;
    private int width = 15;
    private int height = 100;
 
 
    /*** CONSTRUCTOR METHOD ***/
    public player()
    {
 
    }
 
 
    public void paint(Graphics g, main m)
    {
        g.setColor(Color.red);
        g.fillRect(x, y, width, height); 
    }   
}

thanks got it to working. just one last question. i didnt want to post another theard bc its kind of same code so ill post it there.

problem is the my keyListener is not working. i doesnt even go in method public void keyPressed(KeyEvent e). any idea why is this happening. may be this is bc of paintComponent?
note ActionListener, MouseListener, MouseMotionListener seem to be working fine.

i made a smaller program that u can run. i added print statment flag1 and flag2 in keypressed methods. it doesnt out when i press the up key.

also i put @Override on almost every method in main.java. i am not sure if i need them?

main.java

import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
 
import javax.swing.JApplet;
import javax.swing.JPanel;
import javax.swing.Timer;
 
 
public class aaa extends JApplet implements ActionListener, KeyListener, MouseListener, MouseMotionListener
{
 
	/*** class variables ***/
	Display display_class;
 
 
	/*** Timer variable ***/
	Timer timer_class;
 
 
	//###########################################################################################################
	/*** init method ***/
	@Override
	public void init()
	{
		setSize(900, 500);
		display_class = new Display(); 
		setContentPane(display_class);  
		addKeyListener(this);                 //keys
		addMouseListener(this);               //clicking
		addMouseMotionListener(this);         //mouse motion
	}/*** end of init method ***/
 
 
 
 
	//###########################################################################################################
	/*** start method ***/
	@Override
	public void start()
	{
 
		/*** start timer ***/
		if(timer_class == null)
		{
			timer_class = new Timer(20, this); //set up timer only onces
 
		}
		else
		{
			timer_class.stop();
		}
		timer_class.start();                   //start timer jump inside actionperformed method
	}/*** end of start method ***/
 
 
 
	//###########################################################################################################
	/*** game loop ***/
	@Override
	public void actionPerformed(ActionEvent e)
	{
		repaint();
	}/*** end of run method ***/
 
 
 
 
	//###########################################################################################################
	/*** paint method ***/ 
	public class Display extends JPanel
	{
		public void paintComponent(Graphics g)
		{
			super.paintComponent(g);       //redraw paint method. so it doesnt draw on top of each other
 
 
		}/** end of paint method ***/
	}/*** end of display method ***/
 
 
 
 
 
	//###########################################################################################################
		/*** KEY PRESSED ***/
		@Override
		public void keyPressed(KeyEvent e)
		{
			int keys = e.getKeyCode();
 
			System.out.println("flag 1");
				if(keys == KeyEvent.VK_UP)
				{
					System.out.println("flag 2");
				}
		}/*** end of key pressed method ***/
 
		/*** KEY RELEASED ***/
		@Override
		public void keyReleased(KeyEvent e)
		{
			int keys = e.getKeyCode();
 
				if(keys == KeyEvent.VK_UP) { }
				else if(keys == KeyEvent.VK_DOWN) { }
				else if(keys == KeyEvent.VK_E) { }
				else if(keys == KeyEvent.VK_D) { }
		}/*** end of key pressed method ***/
 
		/*** KEY TYPED ***/
		public void keyTyped(KeyEvent e){}
		/*** end of key typed method ***/
 
 
 
 
 
		//###########################################################################################################
		/****** MOUSE *******/
		@Override
		public void mousePressed(MouseEvent e) { }
		public void mouseReleased(MouseEvent e) { }
		public void mouseClicked(MouseEvent e){}
		public void mouseEntered(MouseEvent e) {} //mouse enter applet window
		public void mouseExited(MouseEvent e){}   //mouse exit applet window
 
 
 
 
 
 
		//###########################################################################################################
		/****** MOUSE MOSTION *******/
		@Override
		public void mouseDragged(MouseEvent e){ } //mouse drag
		@Override
		public void mouseMoved(MouseEvent e) {}
}

i did

setFocusable(true);

and it works fine. how about @Override? can you explain which method to use them on?

so there is no harm of using @Override before every methods in project?

but if u mispell class name. wont that give u a error? u end up fixing the class name any way. can i just not use @Override? or is that bad to not use override

if u have a error than the eclipse will tell u that u have a error. even u dont have override. so i dont underend why use orride.

no i am trying to understand why would you want to put override if eclipse or any txt editor tell you the error.

You would use @Override before any method that you believe overrides a parent method. This way you will find out at compile time whether your assumption about the method being a true override is correct. Otherwise you won't know if you are correct until run time, or sometimes never at all.

got it