JTable with custom column model and table model not showing table header

Question

Hello,
I am creating a JTable with a custom table model and a custom column model. However the table header is not being displayed (yes, it is in a JScrollPane). I've shrunk the problem down into a single compileable example:
Thanks for your help.
import javax.swing.*;
import javax.swing.table.*;
public class Test1 extends JFrame
     public static void main(String args[])
          JTable table;
          TableColumnModel colModel=createTestColumnModel();
          TestTableModel tableModel=new TestTableModel();
          Test1 frame=new Test1();
          table=new JTable(tableModel, colModel);
          frame.getContentPane().add(new JScrollPane(table));
          frame.setSize(200,200);
          frame.setVisible(true);
     private static DefaultTableColumnModel createTestColumnModel()
          DefaultTableColumnModel columnModel=new DefaultTableColumnModel();
          columnModel.addColumn(new TableColumn(0));
          return columnModel;
     static class TestTableModel extends AbstractTableModel
          public int getColumnCount()
               return 1;
          public Class<?> getColumnClass(int columnIndex)
               return String.class;
          public String getColumnName(int column)
               return "col";
          public int getRowCount()
               return 1;
          public Object getValueAt(int row, int col)
               return "test";
          public void setValueAt(Object aValue, int rowIndex, int columnIndex)
}Edited by: 802416 on 14-Oct-2010 04:29
added                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        

Answer 1

Kleopatra wrote:
jduprez wrote:
See http://download.oracle.com/javase/6/docs/api/javax/swing/table/TableColumn.html#setHeaderValue(java.lang.Object)
When the TableColumn is created, the default headerValue  is null
So, the header ends up rendered as an empty label (probably of size 0 if the JTable computes its header size based on the renderer's preferred size).nitpicking (can't resist - the alternative is a cleanup round in some not so nice code I produced recently <g>):
- it's not the JTable's business to compute its headers size (and it doesn't, the header's the culprit.) *> - the header should never come up with a zero (or near-to) height: even if there is no title shown, it's still needed as grab to resize/move the columns. So I would consider this sizing behaviour a bug.*
- furthermore, the "really zero" height is a longstanding issue with MetalBorder.TableHeaderBorder (other LAFs size with the top/bottom of their default header cell border) which extends AbstractBorder incorrectly. That's easy to do because AbstractBorder itself is badly implemented
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6459419
Thanks for the opportunity to have some fun :-)
JeanetteNo problem, thanks for the insight :)