How to keep and remove multiple graphic objects in

I have an image and I use pre-defined positions on it to create graphic objects with colors . With a mouse click I try to create some ovals on it with colors . Actually I couldn't achieve this objective. Because , when I click on a pre-defined position I could create an oval on it but when I click on another pre-defined position first oval has gone.

An oval can be removed by click on it twice.

Have look at this ,

public class PrintDialog extends javax.swing.JDialog{
private int count = 0;
private int count_1 = 0;

/**
 * Creates new form PrintFeetDialog
 */
public PrintDialog(java.awt.Frame parent, boolean modal)
{
    super(parent, modal);
    initComponents();
    ImagePanel panel = new ImagePanel("Areas.jpg");
    this.getContentPane().add(panel);
    this.setResizable(false);
    this.setLocationRelativeTo(panel);
    this.pack();
}

private void formMouseClicked(java.awt.event.MouseEvent evt)                                  
{                                      
    // TODO add your handling code here:
    System.out.println("Print y - " + evt.getY());
    System.out.println("Print x - " + evt.getX());

    if ((evt.getX() >= 68 && evt.getX() <= 84) && (evt.getY() >= 44 && evt.getY() <= 72))
    {
        Graphics g = getGraphics();
        count++;
        if (count == 1)
        {
            g.setColor(Color.red);
            g.fillOval(66, 52, 20, 20);
            //  repaint();
        } else if (count > 1)
        {
            g.setColor(new Color(-3692899));
            g.fillOval(66, 52, 20, 20);
            repaint();
            count = 0;
        }
        g.dispose();
    }

    if ((evt.getX() >= 137 && evt.getX() <= 157) && (evt.getY() >= 50 && evt.getY() <= 75))
    {
        Graphics g1 = getGraphics();
        count_1++;
        if (count_1 == 1)
        {
            g1.setColor(Color.RED);
            g1.fillOval(137, 54, 20, 20);
        } else if (count_1 > 1)
        {
            g1.setColor(new Color(-3692899));
            g1.fillOval(66, 52, 20, 20);
            repaint();
            count_1 = 0;
        }
        g1.dispose();
    }
}
}

image panel class

public class ImagePanel extends JPanel{

private Image img;

public ImagePanel(String img, String str)
{
    //this(new ImageIcon(img).getImage());    
}

public ImagePanel(String path)
{
    Image img = new ImageIcon(path).getImage();
    this.img = img;
    Dimension size = new Dimension(img.getWidth(null), img.getHeight(null));
    setPreferredSize(size);
    setMinimumSize(size);
    setMaximumSize(size);
    setSize(size);
    setLayout(null);

     try
    {
        BufferedImage image = ImageIO.read(new File(path));
        int rgb = image.getRGB(66, 52);
        System.out.println("Colour is: "+rgb);
    }
    catch(IOException e)
    {
        e.printStackTrace();
    }
}

public void paintComponent(Graphics g)
{
    super.paintComponent(g);
    g.drawImage(img, 0, 0, null);
}
}

Have any ideas please ?

Thank you .

Don't use getGraphics, this is not how custom painting works, see Painting in AWT and Swing and Performing Custom Painting for more details

The basic idea is, you need some kind of List, into which you add each shape. When the mouseClicked occurs, you iterate through list and check to see if the mouse clicked occur one of the shapes, if it was, you remove the shape from the List, if not, you create a new shape at the point it was clicked and add it to the List.

You then use this List inside the paintComponent method to physically paint the shapes.

This example extends your ImagePanel adding in the custom painting

import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Shape;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Ellipse2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class Test {

    public static void main(String[] args) {
        new Test();
    }

    public Test() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(new DrawPane("/Volumes/Disk02/Dropbox/MegaTokyo/thumnails/0.jpg"));
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class ImagePanel extends JPanel {

        private Image img;

        public ImagePanel(String img, String str) {
            //this(new ImageIcon(img).getImage());    
        }

        public ImagePanel(String path) {
            Image img = new ImageIcon(path).getImage();
            this.img = img;
            try {
                BufferedImage image = ImageIO.read(new File(path));
                int rgb = image.getRGB(66, 52);
                System.out.println("Colour is: " + rgb);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        @Override
        public Dimension getPreferredSize() {
            return img == null ? new Dimension(200, 200) : new Dimension(img.getWidth(this), img.getHeight(this));          
        }

        @Override
        public void paintComponent(Graphics g) {
            super.paintComponent(g);
            g.drawImage(img, 0, 0, null);
        }
    }

    public class DrawPane extends ImagePanel {

        private List<Shape> shapes;

        public DrawPane(String img, String str) {
            super(img, str);
            init();
        }

        public DrawPane(String path) {
            super(path);
            init();
        }

        protected void init() {
            shapes = new ArrayList<>(25);
            addMouseListener(new MouseAdapter() {
                @Override
                public void mouseClicked(MouseEvent e) {
                    boolean clicked = false;
                    Iterator<Shape> it = shapes.iterator();
                    while (it.hasNext()) {
                        Shape shape = it.next();
                        if (shape.contains(e.getPoint())) {
                            it.remove();
                            clicked = true;
                            break;
                        }
                    }
                    if (!clicked) {
                        shapes.add(new Ellipse2D.Double(e.getX() - 10, e.getY() - 10, 20, 20));
                    }
                    repaint();
                }

            });
        }

        @Override
        public void paintComponent(Graphics g) {
            super.paintComponent(g); 
            Graphics2D g2d = (Graphics2D) g.create();
            g2d.setColor(Color.RED);
            for (Shape shape : shapes) {
                g2d.draw(shape);
            }
            g2d.dispose();
        }

    }

}