Change row height of a table by dragging

Question

Hi,
One of my swing projects has a requirement that the user should be able to resize the height of individual rows of a table by dragging the row separator with the mouse.
JTable by default allows us to drag the column separators and change the column width. But the row heights are not adjustable in a similar way.
Is it possible to do so? I guess I will have to write a listener for the rows, don't know how to go about it though.
Any help in this regard would be highly appreciated.
Thanks.

Answer 1

Hi,
Well here is the table you're talkking about. I tried adding the cellrender and listen to the drag event. Could not proceed much though. I am still trying. In the mean time if any of you can progress on this then please let me know.
I've attached my full code listing here.
Thanks.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.table.*;
import java.awt.Cursor;
public class LineNumberTable extends JTable
     private JTable mainTable;
     public LineNumberTable(JTable table){
          super();
          mainTable = table;
          setAutoCreateColumnsFromModel(false);
          setModel(mainTable.getModel());
          setSelectionModel(mainTable.getSelectionModel());
          setAutoscrolls( false );
          addColumn(new TableColumn());
          getColumnModel().getColumn(0).setCellRenderer( mainTable.getTableHeader().getDefaultRenderer());
          //Attaching my cell renderer
          getColumnModel().getColumn(0).setCellRenderer(new myCellRenderer());
          getColumnModel().getColumn(0).setPreferredWidth(10);
          setPreferredScrollableViewportSize(getPreferredSize());
     public boolean isCellEditable(int row, int column) {
          return false;
     public Object getValueAt(int row, int column) {
          return new Integer(row + 1);
     public int getRowHeight(int row) {
          return mainTable.getRowHeight();
     public static void main(String[] args) throws Exception {
          DefaultTableModel model = new DefaultTableModel(100, 5);
          JTable table = new JTable(model);
          JScrollPane scrollPane = new JScrollPane( table );
          JTable lineTable = new LineNumberTable( table );
          scrollPane.setRowHeaderView( lineTable );
          JFrame frame = new JFrame( "Line Number Table" );
          frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
          frame.getContentPane().add(scrollPane, BorderLayout.CENTER);
          frame.setSize(400, 300);
          frame.setVisible(true);
     class myCellRenderer extends DefaultTableCellRenderer implements MouseListener, MouseMotionListener {
          private Point start;
          private Point end;
          public void mouseClicked(MouseEvent e) {
          public void mouseDragged(MouseEvent e) {
          public void mouseEntered(MouseEvent e) {
               setCursor(new Cursor(java.awt.Frame.N_RESIZE_CURSOR));
          public void mouseExited(MouseEvent e) {
               setCursor(new Cursor(java.awt.Frame.N_RESIZE_CURSOR));
          public void mouseMoved(MouseEvent e) {
          public void mousePressed(MouseEvent e) {
               start = e.getPoint();
           public void mouseReleased(MouseEvent e) {
                end = e.getPoint();
                int inc = end.y - start.y;
                LineNumberTable.this.setRowHeight(inc + LineNumberTable.this.getRowHeight());
}