How to add multiple listeners for multiple components in java

Question

i created a java swing application that have multiple jTables. I added multiple mouse listeners for making context menu with anonymous classes. But each time the action listeners are pointing to the first table only. Please help. Each time iam getting is the updated value for first table .

• i have 3 Jtables named jTableNum1, jTableNum2, jTableNum3.
• what i want is cut, copy, paste function for each cell in my three Jtables.
• so i created popumenus & called like:

---

     jTableNum1.addMouseListener(new MouseAdapter() {

               @Override
               public void mouseClicked(MouseEvent e) {
                     rowH = jTableNum1.getSelectedRow();
                    if (e.isPopupTrigger()) {
                       highlightRow(e);
                       doPopup(e);
                   }
               }

               @Override
               public void mouseReleased(MouseEvent e) {

                   if (e.isPopupTrigger()) {
                       highlightRow(e);

                       doPopup(e);
                   }
               }

               protected void doPopup(MouseEvent e) {
                  popupMenu.show(e.getComponent(), e.getX(), e.getY());
               }

               protected void highlightRow(MouseEvent e) {
                   JTable table = (JTable) e.getSource();
                   Point point = e.getPoint();
                   int row = table.rowAtPoint(point);
                   int col = table.columnAtPoint(point);

                   table.setRowSelectionInterval(row, row);
                   table.setColumnSelectionInterval(col, col);
               }

           });

   popupMenu1.add(new clearFuncs (1,rowH));// arg1=  tableNumber , arg2 = the highlighted row)

-

-// similiarly for jTableNum2 & jTableNum3

   public class clearFuncs extends AbstractAction {
   int num;
   int rowH;
   public clearFuncs (int num,int r) {
        this.num = num;
        this.rowH = r;
    putValue(NAME, "Clear");
    }public clearFuncs (int num) {
        this.num = num;
    putValue(NAME, "Clear");
    }


    @Override
    public void actionPerformed(ActionEvent e) {
        int row;
        switch(num){
        case 1: row = jTableNum1.getSelectedRow();
        System.out.println("row = "+rowH);
        jTableNum1.setValueAt("", row, 0);
                break;
        case 2: row = jTableNum2.getSelectedRow();
        System.out.println("row = "+row);
        jTableNum2.setValueAt("", row, 0);
        break;
        case 3: row = jTableNum3.getSelectedRow();
        System.out.println("row = "+row);
        jTableNum3.setValueAt("", row, 0);
        break;

        }          
    }

}               

-

Answer 1

I problem I see is that you are referencing the first table in the Action ClearFuncs. You could easily convert to a generic Action the will be used for all tables. Also same with the MouseAdapter. It couls easily be reconfigured to be used for all the tables, so to avoid repetition. See the example below where I do this. Leave a comment if you have any questions.

import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.Random;

import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPopupMenu;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.DefaultTableModel;

public class TableContextMenuDemo {

    @SuppressWarnings("serial")
    private JTable createTableWithRandomData(int tableNumber) {
        String[] cols = { "col 1", "col 2", "col 3" };
        JTable table = new JTable(new DefaultTableModel(getRandomData(10,
                cols.length), cols)) {
            @Override
            public Dimension getPreferredScrollableViewportSize() {
                return new Dimension(200, 150);
            }
        };
        ClearFuncs action1 = new ClearFuncs(tableNumber, table);
        SayHelloAction action2 = new SayHelloAction();
        JPopupMenu popupMenu = createPopupMenu(action1, action2);
        PopupAdapter listener = new PopupAdapter(popupMenu);
        table.addMouseListener(listener);
        return table;
    }

    class SayHelloAction extends AbstractAction {
        public SayHelloAction() {
            putValue(NAME, "Hello");
        }
        @Override
        public void actionPerformed(ActionEvent e) {
            System.out.println("Hello World");

        }
    }

    private Integer[][] getRandomData(int rows, int cols) {
        Random random = new Random();
        Integer[][] data = new Integer[rows][cols];
        for (int i = 0; i < data.length; i++) {
            for (int j = 0; j < data[i].length; j++) {
                data[i][j] = random.nextInt(Integer.MAX_VALUE);
            }
        }
        return data;
    }

    private JPopupMenu createPopupMenu(Action... actions) {
        JPopupMenu menu = new JPopupMenu();
        for (Action a : actions) {
            menu.add(a);
        }
        return menu;
    }

    class PopupAdapter extends MouseAdapter {
        JPopupMenu popupMenu;

        public PopupAdapter(final JPopupMenu popupMenu) {
            this.popupMenu = popupMenu;
        }

        @Override
        public void mouseClicked(MouseEvent e) {
            if (e.isPopupTrigger()) {
                highlightRow(e);
                doPopup(e);
            }
        }

        @Override
        public void mouseReleased(MouseEvent e) {
            if (e.isPopupTrigger()) {
                highlightRow(e);
                doPopup(e);
            }
        }

        protected void doPopup(MouseEvent e) {
            popupMenu.show(e.getComponent(), e.getX(), e.getY());
        }

        protected void highlightRow(MouseEvent e) {
            JTable table = (JTable) e.getSource();
            Point point = e.getPoint();
            int row = table.rowAtPoint(point);
            int col = table.columnAtPoint(point);

            table.setRowSelectionInterval(row, row);
            table.setColumnSelectionInterval(col, col);
        }

    }

    class ClearFuncs extends AbstractAction {
        int num;

        private JTable table;

        public ClearFuncs(int num, JTable table) {
            this.num = num;
            this.table = table;
            putValue(NAME, "Clear");
        }

        public ClearFuncs(int num) {
            this.num = num;
            putValue(NAME, "Clear");
        }

        @Override
        public void actionPerformed(ActionEvent e) {
            int col = table.getSelectedColumn();
            int row = table.getSelectedRow();
            System.out.println("row = " + row + ", col = " + col + ", table: " + num);
            table.setValueAt("", row, col);
        }
    }

    private void createAndShowGui() {
        JFrame frame = new JFrame();
        frame.setLayout(new FlowLayout());
        for (int i = 1; i <= 3; i++) {
            JTable table = createTableWithRandomData(i);
            JScrollPane scrollPane = new JScrollPane(table);
            scrollPane
                    .setBorder(BorderFactory.createLineBorder(Color.BLACK, 2));
            frame.add(scrollPane);
        }
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new TableContextMenuDemo().createAndShowGui();
            }
        });
    }
}