Solved

(URGENT!)How to draw multiple circles in java swing

Posted on 2006-11-22
8
843 Views
Last Modified: 2013-11-23
Hi there
Im doing a project, and i need to draw multiple circles that represent data; i get the coords and radius(as an arraylist)  from another program.

Im new and awful at java swing; and i need to write a method and constuctors to draw these circles, so i get the coords and radius from another program; i just dont know how to tell the java swing to draw all of them and i've been searching the sun website for days!

 Please may you post some demo code on how to draw circles in jswing to give me a nudge in the right direction??
Thanks in advance!
0
Comment
Question by:NadiaRashid
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 5
  • 3
8 Comments
 
LVL 5

Expert Comment

by:sivachirravuri
ID: 18000725
Hi NadiaRashid.

Check the following link or code. Here is the example.

http://forum.java.sun.com/thread.jspa?threadID=782595


Code:

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Point;
import java.awt.Shape;
import java.awt.Stroke;
import java.awt.event.MouseEvent;
import java.awt.geom.Ellipse2D;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
 
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.event.MouseInputAdapter;
 
public class CirclePanel extends JPanel
{
      private final Map shapesToLocations = new LinkedHashMap();
      private final Stroke stroke = new BasicStroke(3.0f);
      private final Paint paint = Color.BLACK;
 
      public static final void main(String[] args)
      {
            SwingUtilities.invokeLater(new Runnable()
            {
                  public void run()
                  {
                        CirclePanel p = new CirclePanel();
                        p.addShape(new Ellipse2D.Double(10.0, 10.0, 20.0, 20.0));
                        p.addShape(new Ellipse2D.Double(10.0, 40.0, 20.0, 20.0));
 
                        JFrame f = new JFrame();
                        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                        f.setContentPane(p);
                        f.setSize(300, 300);
                        f.setLocationRelativeTo(null);
                        f.setVisible(true);
                  }
 
            });
      }
 
      public CirclePanel()
      {
            MouseHandler h = new MouseHandler();
            addMouseListener(h);
            addMouseMotionListener(h);
      }
 
      public void paintComponent(Graphics g)
      {
            super.paintComponent(g);
            
            Graphics2D g2d = ((Graphics2D) g);
            Paint p = g2d.getPaint();
            Stroke s = g2d.getStroke();
            g2d.setPaint(this.paint);
            g2d.setStroke(this.stroke);
            for (Iterator i = this.shapesToLocations.keySet().iterator(); i.hasNext();)
            {
                  Shape shape = (Shape) i.next();
                  Point location = (Point) this.shapesToLocations.get(shape);
                  g2d.translate(location.x, location.y);
                  g2d.draw(shape);
                  g2d.translate(- location.x, - location.y);
            }
            g2d.setPaint(p);
            g2d.setStroke(s);
      }
 
      public void addShape(Shape shape)
      {
            this.shapesToLocations.put(shape, new Point());
      }
 
      public void removeShape(Shape shape)
      {
            this.shapesToLocations.remove(shape);
      }
 
      private final class MouseHandler extends MouseInputAdapter
      {
            private Shape dragShape = null;
            private Point lastPoint = null;
 
            public void mousePressed(MouseEvent e)
            {
                  lastPoint = e.getPoint();
                  Point p = new Point();
                  for (Iterator i = shapesToLocations.keySet().iterator(); (this.dragShape == null) && i.hasNext();)
                  {
                        Shape shape = (Shape) i.next();
                        Point location = (Point) shapesToLocations.get(shape);
                        p.x = lastPoint.x - location.x;
                        p.y = lastPoint.y - location.y;
                        if (shape.contains(p))
                        {
                              this.dragShape = shape;
                        }
                  }
            }
            
            public void mouseReleased(MouseEvent e)
            {
                  this.dragShape = null;
                  this.lastPoint = null;
            }
 
            public void mouseDragged(MouseEvent e)
            {
                  if (this.dragShape != null)
                  {
                        Point location = (Point) shapesToLocations.get(this.dragShape);
                        location.x += (e.getX() - lastPoint.x);
                        location.y += (e.getY() - lastPoint.y);
                        this.lastPoint = e.getPoint();
                        repaint();
                  }
            }
      }
}

0
 

Author Comment

by:NadiaRashid
ID: 18000766
Hi sivachirravuri

Thanx for such a prompt response. This posting is a bit complicated, could you break it down for me? i just need to understand how i write a method to draw a circle...im confused because some online examples use elipses and others use a Circle method...i really have no idea whats going on with swing.

thanks for your response once again....nadia
0
 

Author Comment

by:NadiaRashid
ID: 18000790
correction, i mean fillOval NOT elipses...ooops :)
0
Get 15 Days FREE Full-Featured Trial

Benefit from a mission critical IT monitoring with Monitis Premium or get it FREE for your entry level monitoring needs.
-Over 200,000 users
-More than 300,000 websites monitored
-Used in 197 countries
-Recommended by 98% of users

 
LVL 5

Accepted Solution

by:
sivachirravuri earned 500 total points
ID: 18001018
I'm only up to chapter four in this Lewis/Loftus book that has the exercise and I really have no intentions of looking into Swing since not much GUI usage is required for the cs class.

something like...

import java.awt.*;

public class Test
{
public Test()
{
}

public void drawCircle (Graphics circle, int xCenter, int yCenter, int radius, Color color)
{
circle.setColor (color);
circle.drawOval (xCenter-radius, yCenter-radius, 2*radius, 2*radius);
}
}

and then for a driver you just do something like...

import java.applet.Applet;
import java.awt.*;

public class Test1 extends Applet
{
public void paint (Graphics page)
{
Color bleh = Color.red;
Test blah = new Test();
Test.drawCircle( ????, 3 4, 6, bleh);
}
}

I know you said not to explicitly call paint (Graphics) but I was wondering if there was maybe a simpler yet possibly less practical way other than JPanel. As you can see, the ?'s show that my approach wasn't successful.
0
 

Author Comment

by:NadiaRashid
ID: 18001029
thankx...i found a graphics one too...from sun.com

public void paint(Graphics g) {
        // Dynamically calculate size information
        // (the canvas may have been resized externally...)
         Dimension size = getSize();
         int d = Math.min(size.width, size.height); // diameter
         int x = (size.width - d)/4;
         int y = (size.height - d)/4;
     
        // draw circle (color already set to foreground)
         g.fillOval(x, y, d, d);
         g.setColor(Color.black);
         g.drawOval(x, y, d, d);
     
      }

except now it's hiding all the other stuff i have in my GUI so i need to find a JPanel method for drawing a circle...anyone got anything???
 
thanks for your input sivachirravuri
cheers
0
 
LVL 5

Expert Comment

by:sivachirravuri
ID: 18001037
Welcome. Did you find my second input understandable...? I hope it will be useful
0
 

Author Comment

by:NadiaRashid
ID: 18001104
second input is understandable...now for this post i just put up...just realised its using graphics tooo...but i sorta have direction on how to draw a circle....so you certainly did help...thank you!
0

Featured Post

The Ultimate Checklist to Optimize Your Website

Websites are getting bigger and complicated by the day. Video, images, custom fonts are all great for showcasing your product/service. But the price to pay in terms of reduced page load times and ultimately, decreased sales, can lead to some difficult decisions about what to cut.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

In this post we will learn different types of Android Layout and some basics of an Android App.
Make the most of your online learning experience.
Six Sigma Control Plans
Progress

717 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question