an error in paint method

[hopey]

hi all ,
i am having an error
but can't solve it

here it is:

protected void paint(Graphics g)
1 error

i am drawing a circle by using the mouse
my class is:

public class Circle_mousedraw extends JFrame implements MouseListener,MouseMotionListener

so the program give this error when i run it

can any one help me?

[Fubarable]

You need to post more of the error message and more of your code otherwise I doubt anyone will be able to guess what is wrong based on the information presented.

One problem I see off the bat though is that you seem to be drawing directly to the JFrame. Don't do that. You are far better off extending a JPanel and drawing in that by overriding its paintComponent method. For one, by doing this you automatically get double-buffering.

Good luck!

[hopey]

ok this is my code

/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/

package javaapplication21;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.geom.GeneralPath;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JLabel;

/**
*
* @author Free User
*/
public class Circle_mousedraw extends JPanel implements MouseListener,MouseMotionListener {

Point[] points;
GeneralPath circle;
final int INC = 8;
JLabel statusBar; //mouse coordinate bar
// our constructor

public Circle_mousedraw()
{
initPoints();
// to fill the circle we need to make something
// that we can fill: a geometry primitive
initCircle();
// the stauts bar of the mouse
statusBar = new JLabel("mouse outside the panel");
add(statusBar,BorderLayout.SOUTH);
//adding mouse events
addMouseListener(this);
addMouseMotionListener(this);

}

//here we will substitute in the circle equation

private void initPoints()
{
int numberOfPoints = 360/INC;
points = new Point[numberOfPoints];
double cx = 200.0;
double cy = 200.0;
double r = 100.0;
int count = 0;
for(int theta = 0; theta < 360; theta+=INC)
{
int x = (int)(cx + r * Math.cos(Math.toRadians(theta)));
int y = (int)(cy + r * Math.sin(Math.toRadians(theta)));
points[count++] = new Point(x, y);
}
}

//we begine the first step of the circle drawing

private void initCircle()
{
circle = new GeneralPath();
for(int j = 0; j < points.length; j++)
{
if(j == 0)
circle.moveTo(points[j].x, points[j].y);
else
circle.lineTo(points[j].x, points[j].y);
}
circle.closePath();
}



////////////////


// @Override
@Override
protected void paintComponent (Graphics g)
{
super.paint(g);
Graphics2D g2 = (Graphics2D)g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASIN G,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setPaint(Color.white);
g2.fill(circle);
g2.setPaint(Color.BLUE);
Point p1 = points[0];
for(int j = 1; j <= points.length; j++)
{
Point p2 = points[j % points.length];
g2.drawLine(p1.x, p1.y, p2.x, p2.y);
p1 = p2;
}
}



// handel event when mouse is clicked

public void mouseClicked(MouseEvent mouse) {
//show the coordinates of x&y when the mouse clicked
statusBar.setText(String.format("clicked at [%d, %d]", mouse.getX(),mouse.getY()));
// Get the location of the current mouse click.
int cx = mouse.getX();
int cy = mouse.getY();
// Tell the panel that we need to redraw things.
repaint();
}



// handel event when mouse is pressed


public void mousePressed(MouseEvent mouse) {

//show the coordinates of x&y when the mouse pressed
statusBar.setText(String.format("presed at [%d, %d]", mouse.getX(),mouse.getY())); }
// handel event when mouse is released

public void mouseReleased(MouseEvent mouse) {

//show the coordinates of x&y when the mouse pressed
statusBar.setText(String.format("presed at [%d, %d]", mouse.getX(),mouse.getY())); }


// handel event when mouse is entered the area

public void mouseEntered(MouseEvent mouse) {

//show the coordinates of x&y when the mouse pressed
statusBar.setText(String.format("presed at [%d, %d]", mouse.getX(),mouse.getY())); }


//when the mouse exit the area

public void mouseExited(MouseEvent mouse) {

statusBar.setText("exit"); }



////////////////////////


//Mousemotionlistener event handlers

public void mouseDragged(MouseEvent mouse) {
//show the coordinates of x&y when the mouse dragged
statusBar.setText(String.format("draged at [%d, %d]", mouse.getX(),mouse.getY())); }

public void mouseMoved(MouseEvent mouse) {
//show the coordinates of x&y when the mouse moved
statusBar.setText(String.format("moved at [%d, %d]", mouse.getX(),mouse.getY())); }



//////////////



public static void main(String[] args) {
Circle_mousedraw c1 = new Circle_mousedraw ();


c1.setVisible(true);
JFrame f = new JFrame("my circle");
f.setContentPane(new Circle_mousedraw());
f.setSize(400,400);
f.setLocation(200,200);
f.setVisible(true);
}


}

and this is the error

Exception in thread "AWT-EventQueue-0" java.lang.StackOverflowError

the program run but it seems to be a run time error
the window appear but nothing happen in it

i don't know why?

[Fubarable]

You're calling the wrong super method here:

  protected void paintComponent(Graphics g)
  {
    super.paint(g);
    //....

Since paint calls paintComponent, this will result in an endless loop and a heap overrun.

Much better is to call the super method of the same painting type method, paintComponent,

  protected void paintComponent(Graphics g)
  {
    super.paintComponent(g);
    //....

[hopey]

oh wht a mistake

thanks alot

the code run but didn't make wht i need

i need to draw the circle by the mouse
(as in paint program)

if u have any idea how to do this i will be thankful really

[rexicon]

Worked for me

[Fubarable]

rexicon, why are you spamming the fora with these non-sense posts?

[hopey]

sorry can i ask once more?

the code i wrote
draw the circle with constant radius and center

i want to make them variables
also i need the circle be drawn using the mouse not automatically

can u help me ?
this is the last code i have wrote

/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/

package javaapplication21;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
//import java.awt.RenderingHints;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.geom.GeneralPath;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JLabel;

/**
*
* @author Free User
*/
public class Circle_mousedraw extends JPanel implements MouseListener,MouseMotionListener {

Point[] points;
GeneralPath circle;
final int INC = 3;
JLabel statusBar; //mouse coordinate bar
// constructor
public Circle_mousedraw()
{
initPoints();
// to fill the circle we need to make something
// that we can fill: a geometry primitive
initCircle();

// the stauts bar of the mouse
statusBar = new JLabel("mouse outside the panel");
add(statusBar,BorderLayout.SOUTH);

//adding mouse events
addMouseListener(this);
addMouseMotionListener(this);

}

//here we will substitute in the circle equation
public void initPoints()
{
int numberOfPoints = 360/INC;
points = new Point[numberOfPoints];
double cx = 200.0;
double cy = 200.0;
double r = 100.0;
int count = 0;
for(int theta = 0; theta < 360; theta+=INC)
{
int x = (int)(cx + r * Math.cos(Math.toRadians(theta)));
int y = (int)(cy + r * Math.sin(Math.toRadians(theta)));
points[count++] = new Point(x, y);
}
}


//we begine the first step of the circle drawing
public void initCircle()
{
circle = new GeneralPath();
for(int j = 0; j < points.length; j++)
{
if(j == 0)
circle.moveTo(points[j].x, points[j].y);
else
circle.lineTo(points[j].x, points[j].y);
}
circle.closePath();
}





////////////////


// @Override
@Override
protected void paintComponent (Graphics g)
{
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;
// g2.setRenderingHint(RenderingHints.KEY_ANTIALIASIN G,
// RenderingHints.VALUE_ANTIALIAS_ON);
g2.setPaint(Color.white);
g2.fill(circle);
g2.setPaint(Color.BLUE);
Point p1 = points[0];
for(int j = 1; j <= points.length; j++)
{
Point p2 = points[j % points.length];
g2.drawLine(p1.x, p1.y, p2.x, p2.y);
p1 = p2;
}
}



// handel event when mouse is clicked

public void mouseClicked(MouseEvent mouse) {
//show the coordinates of x&y when the mouse clicked
statusBar.setText(String.format("clicked at [%d, %d]", mouse.getX(),mouse.getY()));
}



// handel event when mouse is pressed


public void mousePressed(MouseEvent mouse) {

//show the coordinates of x&y when the mouse pressed
statusBar.setText(String.format("presed at [%d, %d]", mouse.getX(),mouse.getY()));

// Get the location of the current mouse click.
int x = mouse.getX();
int y = mouse.getY();
int r = mouse.getX();
}


// handel event when mouse is released

public void mouseReleased(MouseEvent mouse) {

//show the coordinates of x&y when the mouse pressed
statusBar.setText(String.format("presed at [%d, %d]", mouse.getX(),mouse.getY()));

// Get the location of the current mouse click.
int x = mouse.getX();
int y = mouse.getY();
int r = mouse.getX();
// Tell the panel that we need to redraw things.
repaint();
}


// handel event when mouse is entered the area

public void mouseEntered(MouseEvent mouse) {

//show the coordinates of x&y when the mouse pressed
statusBar.setText(String.format("presed at [%d, %d]", mouse.getX(),mouse.getY())); }

//when the mouse exit the area

public void mouseExited(MouseEvent mouse) {

statusBar.setText("exit"); }



////////////////////////


//Mousemotionlistener event handlers

public void mouseDragged(MouseEvent mouse) {
//show the coordinates of x&y when the mouse dragged
statusBar.setText(String.format("draged at [%d, %d]", mouse.getX(),mouse.getY()));

// Get the location of the current mouse click.
int x = mouse.getX();
int y = mouse.getY();
int r = mouse.getX();

// Tell the panel that we need to redraw things.
repaint();

}

public void mouseMoved(MouseEvent mouse) {
//show the coordinates of x&y when the mouse moved
statusBar.setText(String.format("moved at [%d, %d]", mouse.getX(),mouse.getY())); }



//////////////



public static void main(String[] args) {
Circle_mousedraw c1 = new Circle_mousedraw ();


c1.setVisible(true);
JFrame f = new JFrame("my circle");
f.setContentPane(new Circle_mousedraw());
f.setSize(400,400);
f.setLocation(200,200);
f.setVisible(true);
}


}

i hope i find the true answer
thanks in advance