Change column header in a JTable

Question

This is my table right now :

This is the code that I can change the column title:

table.getColumnModel().getColumn(0).setHeaderValue("Lecturersssss");

But the column title would not change until I hover the mouse on the Lecturer column header.

Even when i use table.repaint() after this code, it won't change. Do you guys have any idea how can I solve this issue ?

Thanks.

Are you using a `MouseEvent` to do this? – chalitha geekiyanage Feb 05 '16 at 06:11 — chalitha geekiyanage, Feb 05 '16 at 06:11
no, i have that code inside an actionlistener of a button – Nathan Drake Feb 05 '16 at 06:14 — Nathan Drake, Feb 05 '16 at 06:14

score 4 · Accepted Answer · answered Feb 05 '16 at 06:32

4

JTableHeader header= table.getTableHeader();
TableColumnModel colMod = header.getColumnModel();
TableColumn tabCol = colMod.getColumn(0);
tabCol.setHeaderValue("Lecturersssss");
header.repaint();

answered Feb 05 '16 at 06:32

chalitha geekiyanage

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This should work. It is probably not even necessary to repaint. – Costis Aivalis Feb 05 '16 at 07:29
i still have the same issue – Nathan Drake Feb 05 '16 at 09:13
i have a messy code: http://pastebin.com/phFGAaXV i don't know whether it can helps or not – Nathan Drake Feb 05 '16 at 09:21

score 2 · Answer 2 · answered Feb 05 '16 at 10:19

Chalita's suggestion should work. Here's sanity check short demonstration program. Click the button to change the column header text. Works on my environment at least...

import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import javax.swing.table.*;

public class TTT extends JFrame {
    JTable t;
    public TTT() {
        setLayout(new BorderLayout());
        Object[] cols= new Object[]{"Col1","Col2","Col3"};
        Object[][] vals= new Object[][]{{5,6,7}};
        t = new JTable(vals,cols);
        add(new JScrollPane(t),BorderLayout.CENTER);
        JButton b = new JButton("Change Column Header");
        b.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent arg0) {
                Random r = new Random();
                Enumeration<TableColumn> e = t.getColumnModel().getColumns();
                while( e.hasMoreElements( ) )
                    e.nextElement().setHeaderValue("Col"+Math.abs(r.nextInt()));
                t.getTableHeader().repaint();
            }
        });
        b.setPreferredSize(new Dimension(1,25));
        add(b,BorderLayout.SOUTH);
        setSize(500,150);
    }
    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new TTT().setVisible(true);
            }
        });
    }
}

thanks for your example, instead of table.getTableHeader().repaint(); i've been used table.repaint(); problem solved — Nathan Drake, Feb 05 '16 at 10:53
under jdk 8 thet table.repaint() doesn't change anything. sigh... :'( — gumuruh, Dec 06 '20 at 15:31
@gumuruh I would expect this to work also in JDK8, perhaps a new question is in order? — TT., Dec 06 '20 at 15:56

Change column header in a JTable

2 Answers2