TITLE SHOULD ACTUALLY BE: how to get mouselistener to work on method in an class in java

If I click a circle it should change the color of the circle. But, I am having difficult getting it to work.
Help appreciated.

Main just calls this class and calls the init function.

/*
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 * and open the template in the editor.
 */

package hopfieldnet;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseListener;
import javax.swing.*;



public class hop2d extends JFrame{
    static final int MAXPATTERNS = 4;
    static final int ROWS = 8;                       // Dimensions of the images
    static final int COLS = 8;
    static final int MAINSCREEN = 0;        // Constants for drawing the screens
    static final int TRAINPATTS = 1;

    JButton viewTrainPattern;   // Click on this button to view the training patterns
    JButton singleStep;
    MyPanel patPanel ;// Click on this button to run a test one (more) step
    int trainPatterns[][][] = new int [MAXPATTERNS][COLS][ROWS];
    int testPattern[][] = new int [COLS][ROWS];
    int t[][][][] = new int [COLS][ROWS][COLS][ROWS];   // connection weights
    int screenMode = MAINSCREEN;

    public void init()
    {
        JFrame frame = new JFrame("Hopfield Net");
        JPanel panel = new JPanel();
        patPanel = new MyPanel(200, 300);
        JLabel panel1 = new JLabel();
        ItemHandler itemHandler = new ItemHandler();
        singleStep = new JButton("Single Step");
        viewTrainPattern = new JButton("View Train Pattern");
        singleStep.setSize(30, 15);
        viewTrainPattern.setSize(30,15);
        frame.setSize(600, 600);
        panel.setBounds(150, 100, 180 , 120);
        singleStep.addActionListener(itemHandler);
        viewTrainPattern.addActionListener(itemHandler);
        panel.add(singleStep);
        panel.add(viewTrainPattern);
        frame.getContentPane().add(panel, BorderLayout.NORTH);
        setupTrainingPatterns();
        // Initialise test pattern to blank
        for (int i = 0; i < COLS; i++)
            for (int j = 0; j < ROWS; j++)
                testPattern[i][j] = -1;
        panel1.setText(testPattern.toString());
        frame.getContentPane().add(patPanel, BorderLayout.CENTER);
        frame.setVisible(true);
    }
    


    public void setupTrainingPatterns ()
    {

        initialisePattern(0,"00000000","01111110","01000010","01000010","01000010","01000010","01111110","00000000");
        initialisePattern(1,"00000000","00010000","00010000","00010000","11111110","00010000","00010000","00010000");
        initialisePattern(2,"10011110","10010010","10010010","10010010","10010010","10010010","10010010","11110011");
        initialisePattern(3,"00000000","00010000","00011000","00100100","00100100","01000010","01000010","11111111");
        //retrain();
    }

    public void initialisePattern (int patNum, String line0, String line1, String line2, String line3,String line4, String line5, String line6, String line7)
    {
        initialiseline(patNum,0,line0);
        initialiseline(patNum,1,line1);
        initialiseline(patNum,2,line2);
        initialiseline(patNum,3,line3);
        initialiseline(patNum,4,line4);
        initialiseline(patNum,5,line5);
        initialiseline(patNum,6,line6);
        initialiseline(patNum,7,line7);
    }

    public void initialiseline (int patNum, int lineNum, String line)
    {
        for (int i = 0; i < line.length(); i++)
            if (line.charAt(i) == '1')
                trainPatterns[patNum][i][lineNum] = +1;
            else
                trainPatterns[patNum][i][lineNum] = -1;
    }

//    @Override
//    public void paint (Graphics g)
//    {
//        switch (screenMode)
//        {
//            case MAINSCREEN : drawMainScreen(g);  break;
//            case TRAINPATTS : drawTrainingPatterns(g); break;
//        }
//    }

//    public void drawMainScreen (Graphics g)
//    {
//        g.drawString("Test pattern",50,40);
//        for (int j = 0; j < ROWS; j++)
//            for (int i = 0; i < COLS; i++)
//                drawCell(g,testPattern[i][j],50 + 12 * i, 50 + 12 * j);
//    }

//    public void drawTrainingPatterns (Graphics g)
//    {
//        for (int pattern = 0; pattern < MAXPATTERNS; pattern++)
//        {
//            g.drawString("Pattern " + pattern, 5 + 110 * pattern, 45);
//            for (int i = 0; i < COLS; i++)
//                for (int j = 0; j < ROWS; j++)
//                drawCell(g, trainPatterns[pattern][i][j],5 + 110 * pattern + 12 * i, 50 + 12 * j);
//        }
//    }

    // Draw a particular value of 1 or -1
    public void drawCell (Graphics g, int value, int x, int y)
    {
        if (value == 1)
            g.setColor(Color.black);
        else
            g.setColor(Color.white);
            g.fillOval(x,y,12,12);         // Draws a white circle or a black one
            g.setColor(Color.black);
            g.drawOval(x,y,12,12);
    }

    public void runSingleStep ()
    {
        int new_mu[][] = new int[COLS][ROWS];   // Holds new values of mu before copying back
        int i,j,k,l;                                                           // FOR loop counters
        for (k = 0; k < COLS; k++)
            for (l = 0; l < ROWS; l++)
            {
                int sum = 0;
                for (i = 0; i < COLS; i++)
                    for (j = 0; j < ROWS; j++)
                        sum += t[i][j][k][l] * testPattern[i][j];
                        if (sum > 0)    // Pass through hard-limiting non-linearity
                            new_mu[k][l] = 1;
                        else
                            new_mu[k][l] = -1;
            }
            // Now copy the values present in new_mu back into the test pattern ready to be displayed
            for (i = 0; i < COLS; i++)
                for (j = 0; j < ROWS; j++)
                    testPattern[i][j] = new_mu[i][j];
           repaint();
    }

    public void retrain ()
    {
        for (int i = 0; i < COLS; i++)
            for (int j = 0; j < ROWS; j++)
                for (int k = 0; k < COLS; k++)
                    for (int l = 0; l < ROWS; l++)
                        if (i == k && j == l)
                            t[i][j][k][l] = 0;
                        else
                        {
                            int sum = 0;
                            for (int pattern = 0; pattern < MAXPATTERNS; pattern++)
                                sum += trainPatterns[pattern][i][j] * trainPatterns[pattern][k][l];
                                t[i][j][k][l] = sum;
                        }
    }
    
    

class ItemHandler implements ActionListener{
    public void actionPerformed(ActionEvent e)
    {
        if (e.getSource() == viewTrainPattern)
        {
            if (viewTrainPattern.getLabel() == "View Training Patterns")
            {
                viewTrainPattern.setLabel("View Main Screen");
                patPanel.setBackground(Color.red);
                screenMode = TRAINPATTS;
                patPanel.setScreenMode(screenMode);
                repaint();
            }
            else
            {
                viewTrainPattern.setLabel("View Training Patterns");
                patPanel.setBackground(Color.GREEN);
                screenMode = MAINSCREEN;
                patPanel.setScreenMode(screenMode);
                repaint();
            }
        }
        if (e.getSource() == singleStep)
        {
             runSingleStep();
             patPanel.setBackground(Color.BLUE);
             repaint();
        }
    }
}

    class MyPanel extends JPanel
    {
        private int width=100, height=100;
        public MyPanel(int w, int h)
        {
            width=(w>=0?w:100);
            height=(h>=0?h:100);
        }
        @Override
        public void paintComponent(Graphics g)
        {
            super.paintComponent(g);
            switch (screenMode)
            {
                case MAINSCREEN: drawMainScreen(g); break;
                case TRAINPATTS: drawTrainingPatterns(g); break;
            }
        }
        
        public void setScreenMode(int c){
            screenMode=c;
        }
        public void drawMainScreen (Graphics g){
            g.drawString("Test pattern",50,40);
            for (int j = 0; j < ROWS; j++)
                for (int i = 0; i < COLS; i++)
                    drawCell(g,testPattern[i][j],50 + 12 * i, 50 + 12 * j);
        }

        public void drawTrainingPatterns (Graphics g)    {
            for (int pattern = 0; pattern < MAXPATTERNS; pattern++)
            {
                g.drawString("Pattern " + pattern, 5 + 110 * pattern, 45);
                for (int i = 0; i < COLS; i++)
                    for (int j = 0; j < ROWS; j++)
                    drawCell(g, trainPatterns[pattern][i][j],5 + 110 * pattern + 12 * i, 50 + 12 * j);
            }
        }
    }
}

i have 2 panels because i have two windows...
The draw cell method creates a graphic object and i want to change color depending on if the graphic object is selected or not. I can't even create a handle to it.

Added mouse listener it works whenever I click anywhere not only when I click on the circles

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

package hopfieldnet;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.*;



public class hop2d extends JFrame{
    static final int MAXPATTERNS = 4;
    static final int ROWS = 8;                       // Dimensions of the images
    static final int COLS = 8;
    static final int MAINSCREEN = 0;        // Constants for drawing the screens
    static final int TRAINPATTS = 1;

    JButton viewTrainPattern;   // Click on this button to view the training patterns
    JButton singleStep;
    MyPanel patPanel ;// Click on this button to run a test one (more) step
    int trainPatterns[][][] = new int [MAXPATTERNS][COLS][ROWS];
    int testPattern[][] = new int [COLS][ROWS];
    int t[][][][] = new int [COLS][ROWS][COLS][ROWS];   // connection weights
    int screenMode = MAINSCREEN;

    public void init()
    {
        JFrame frame = new JFrame("Hopfield Net");
        JPanel panel = new JPanel();
        patPanel = new MyPanel(200, 300);
        JLabel panel1 = new JLabel();
        ItemHandler itemHandler = new ItemHandler();
        singleStep = new JButton("Single Step");
        viewTrainPattern = new JButton("View Train Pattern");
        singleStep.setSize(30, 15);
        viewTrainPattern.setSize(30,15);
        frame.setSize(600, 600);
        panel.setBounds(150, 100, 180 , 120);
        singleStep.addActionListener(itemHandler);
        viewTrainPattern.addActionListener(itemHandler);
        panel.add(singleStep);
        panel.add(viewTrainPattern);
        frame.getContentPane().add(panel, BorderLayout.NORTH);
        
        setupTrainingPatterns();
        // Initialise test pattern to blank
        for (int i = 0; i < COLS; i++)
            for (int j = 0; j < ROWS; j++)
                testPattern[i][j] = -1;
        panel1.setText(testPattern.toString());
        frame.getContentPane().add(patPanel, BorderLayout.CENTER);
        frame.setVisible(true);
    }



    public void setupTrainingPatterns ()
    {

        initialisePattern(0,"00000000","01111110","01000010","01000010","01000010","01000010","01111110","00000000");
        initialisePattern(1,"00000000","00010000","00010000","00010000","11111110","00010000","00010000","00010000");
        initialisePattern(2,"10011110","10010010","10010010","10010010","10010010","10010010","10010010","11110011");
        initialisePattern(3,"00000000","00010000","00011000","00100100","00100100","01000010","01000010","11111111");
        //retrain();
    }

    public void initialisePattern (int patNum, String line0, String line1, String line2, String line3,String line4, String line5, String line6, String line7)
    {
        initialiseline(patNum,0,line0);
        initialiseline(patNum,1,line1);
        initialiseline(patNum,2,line2);
        initialiseline(patNum,3,line3);
        initialiseline(patNum,4,line4);
        initialiseline(patNum,5,line5);
        initialiseline(patNum,6,line6);
        initialiseline(patNum,7,line7);
    }

    public void initialiseline (int patNum, int lineNum, String line)
    {
        for (int i = 0; i < line.length(); i++)
            if (line.charAt(i) == '1')
                trainPatterns[patNum][i][lineNum] = +1;
            else
                trainPatterns[patNum][i][lineNum] = -1;
    }

//    @Override
//    public void paint (Graphics g)
//    {
//        switch (screenMode)
//        {
//            case MAINSCREEN : drawMainScreen(g);  break;
//            case TRAINPATTS : drawTrainingPatterns(g); break;
//        }
//    }

//    public void drawMainScreen (Graphics g)
//    {
//        g.drawString("Test pattern",50,40);
//        for (int j = 0; j < ROWS; j++)
//            for (int i = 0; i < COLS; i++)
//                drawCell(g,testPattern[i][j],50 + 12 * i, 50 + 12 * j);
//    }

//    public void drawTrainingPatterns (Graphics g)
//    {
//        for (int pattern = 0; pattern < MAXPATTERNS; pattern++)
//        {
//            g.drawString("Pattern " + pattern, 5 + 110 * pattern, 45);
//            for (int i = 0; i < COLS; i++)
//                for (int j = 0; j < ROWS; j++)
//                drawCell(g, trainPatterns[pattern][i][j],5 + 110 * pattern + 12 * i, 50 + 12 * j);
//        }
//    }

    // Draw a particular value of 1 or -1
    public void drawCell (Graphics g, int value, int x, int y)
    {
        if (value == 1)
            g.setColor(Color.black);
        else
            g.setColor(Color.white);
            g.fillOval(x,y,12,12);         // Draws a white circle or a black one
            g.setColor(Color.black);
            g.drawOval(x,y,12,12);
    }


    public void runSingleStep ()
    {
        int new_mu[][] = new int[COLS][ROWS];   // Holds new values of mu before copying back
        int i,j,k,l;                                                           // FOR loop counters
        for (k = 0; k < COLS; k++)
            for (l = 0; l < ROWS; l++)
            {
                int sum = 0;
                for (i = 0; i < COLS; i++)
                    for (j = 0; j < ROWS; j++)
                        sum += t[i][j][k][l] * testPattern[i][j];
                        if (sum > 0)    // Pass through hard-limiting non-linearity
                            new_mu[k][l] = 1;
                        else
                            new_mu[k][l] = -1;
            }
            // Now copy the values present in new_mu back into the test pattern ready to be displayed
            for (i = 0; i < COLS; i++)
                for (j = 0; j < ROWS; j++)
                    testPattern[i][j] = new_mu[i][j];
           repaint();
    }

    public void retrain ()
    {
        for (int i = 0; i < COLS; i++)
            for (int j = 0; j < ROWS; j++)
                for (int k = 0; k < COLS; k++)
                    for (int l = 0; l < ROWS; l++)
                        if (i == k && j == l)
                            t[i][j][k][l] = 0;
                        else
                        {
                            int sum = 0;
                            for (int pattern = 0; pattern < MAXPATTERNS; pattern++)
                                sum += trainPatterns[pattern][i][j] * trainPatterns[pattern][k][l];
                                t[i][j][k][l] = sum;
                        }
    }



    class ItemHandler implements ActionListener{
        public void actionPerformed(ActionEvent e)
        {
            if (e.getSource() == viewTrainPattern)
            {
                if (viewTrainPattern.getLabel() == "View Training Patterns")
                {
                    viewTrainPattern.setLabel("View Main Screen");
                    patPanel.setBackground(Color.red);
                    screenMode = TRAINPATTS;
                    patPanel.setScreenMode(screenMode);
                    repaint();
                }
                else
                {
                    viewTrainPattern.setLabel("View Training Patterns");
                    patPanel.setBackground(Color.GREEN);
                    screenMode = MAINSCREEN;
                    patPanel.setScreenMode(screenMode);
                    repaint();
                }
            }
            if (e.getSource() == singleStep)
            {
                 runSingleStep();
                 patPanel.setBackground(Color.BLUE);
                 repaint();
            }
        }
    }

    class MyPanel extends JPanel
    {
        private int width=100, height=100;
        public MyPanel(int w, int h)
        {
            addMouseListener(new MouseAdapter() {
                @Override
            public void mousePressed(MouseEvent me) {
            System.out.println("This is working");
          }
        });

            width=(w>=0?w:100);
            height=(h>=0?h:100);
        }
        @Override
        public void paintComponent(Graphics g)
        {
            super.paintComponent(g);
            switch (screenMode)
            {
                case MAINSCREEN: drawMainScreen(g); break;
                case TRAINPATTS: drawTrainingPatterns(g); break;
            }
        }

        public void setScreenMode(int c){
            screenMode=c;
        }
        public void drawMainScreen (Graphics g){
            g.drawString("Test pattern",50,40);
            for (int j = 0; j < ROWS; j++)
                for (int i = 0; i < COLS; i++)
                    drawCell(g,testPattern[i][j],50 + 12 * i, 50 + 12 * j);
        }

        public void drawTrainingPatterns (Graphics g)    {
            for (int pattern = 0; pattern < MAXPATTERNS; pattern++)
            {
                g.drawString("Pattern " + pattern, 5 + 110 * pattern, 45);
                for (int i = 0; i < COLS; i++)
                    for (int j = 0; j < ROWS; j++)
                    drawCell(g, trainPatterns[pattern][i][j],5 + 110 * pattern + 12 * i, 50 + 12 * j);
            }
        }
    }
}

In the line 125 (drawCell-method) write

System.out.println(new Rectangle(x,y,12,12));

Inside this rectangles circles are drawn on the panel
If you pressed mouse, you know position of mouse

// convert mousePosition to i,j array indexes
    public void mousePressed(MouseEvent e) {

        Point p = e.getPoint();//mouse position
        System.out.println(p);
        Rectangle lastCircle = new Rectangle(134, 134, 12, 12); //test example

        boolean b = lastCircle.contains(p); //check, is point p inside rectangle?
        if (b) {
            System.out.println("Mouse is inside a last circle, table indexes i,j are ...");
        }
        // useing drawCell(g, testPattern[i][j], 50 + 12 * i, 50 + 12 * j); parameters
        // and g.drawOval(x, y, 12, 12); parameters
        // you can reverse calculate indexes i and j !
        // store i,j outside, and use them in other parts of program
       
    }
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