Grid header for JTable

[Zach Donovan]

How do i create a grid header on the top left corner of a jtable?
Clicking on it will highlight every cell in the jtable.

[Craig Wood]

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.table.DefaultTableModel;
 
public class GridHeader implements ActionListener
{
    JTable table;
 
    public void actionPerformed(ActionEvent e)
    {
        ListSelectionModel lsm = table.getSelectionModel();
        if(lsm.isSelectionEmpty())
            lsm.setSelectionInterval(0, table.getRowCount()-1);
        else
            lsm.clearSelection();
    }
 
    private JScrollPane getContent()
    {
        JButton gridControl = new JButton("select");
        gridControl.addActionListener(this);
        JPanel rowHeader = new JPanel();
        Dimension d = rowHeader.getPreferredSize();
        d.width = gridControl.getPreferredSize().width;
        rowHeader.setPreferredSize(d);
        table = new JTable(new DefaultTableModel(16, 4));
        d = table.getTableHeader().getPreferredSize();
        d.height = gridControl.getPreferredSize().height;
        table.getTableHeader().setPreferredSize(d);
        JScrollPane scrollPane = new JScrollPane(table);
        scrollPane.setRowHeaderView(rowHeader);
        scrollPane.setCorner(JScrollPane.UPPER_LEFT_CORNER, gridControl);
        return scrollPane;
    }
 
    public static void main(String[] args)
    {
        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.getContentPane().add(new GridHeader().getContent());
        f.setSize(400,400);
        f.setLocation(200,200);
        f.setVisible(true);
    }
}

[Zach Donovan]

Thanks Craig for the fast reply...thats exactly what i need

Cheers

[Zach Donovan]

Hi,

is there another way of highlighting...instead of selecting every cell
i just want to highlight them, not selecting all?

[Craig Wood]

    public void actionPerformed(ActionEvent e)
    {
        TableCellRenderer renderer = table.getCellRenderer(0,0);
        Component c = table.prepareRenderer(renderer, 0, 0);
        Color bg = table.getBackground();
        if( c.getBackground().equals(Color.yellow) )
            c.setBackground(bg);
        else
            c.setBackground(Color.yellow);
        table.repaint();
    }

[Zach Donovan]

Hi Craig,

if i want individual cell selection to work, i set table.setCellSelectionEnabled(true);

in this case the selection of the whole grid doesn't work anymore.

how do i make it work?

thanks in advance.
cheers

[Craig Wood]

    /** from <a href="http://javaalmanac.com/egs/javax.swing.table/Sel.html" target="_blank" rel="nofollow">Programmatically Making Selections in a JTable Component</a> */
    public void actionPerformed(ActionEvent e)
    {
        if(table.getSelectedRows().length < table.getRowCount())
        {
            boolean toggle = false;
            boolean extend = false;
            table.changeSelection(0,0,toggle,extend);
            extend = true;
            int row = table.getRowCount()-1;
            int col = table.getColumnCount()-1;
            table.changeSelection(row, col, toggle, extend);
        }
        else
            table.clearSelection();
        table.repaint();
    }