JTable Focus Rectangle

Question

When navigating around my table the focus recatangle is not shown - but the correct cell is selected.
A single click selects a cell, but I need to double click to see the focus triangle.
I would like the focus rectangle to appear when the cell is selected.
Any ideas?

Answer 1

Actually I was't thinking clearly when you asked about a "focus rectangle (which is why I always recommend a simple demo program that shows your problem). I thought you where asking about the "dotted line focus rectangle" that appears on components like JButton.
Anyway here is a simple table and not that the "focus rectangle" appears on all cells except the column with boolean values.
import java.awt.*;
import java.util.*;
import javax.swing.*;
public class TableBasic extends JFrame
     public TableBasic()
          String[] columnNames = {"Date", "String", "Integer", "Boolean"};
          Object[][] data =
               {new Date(), "A", new Integer(1), Boolean.TRUE },
               {new Date(), "B", new Integer(2), Boolean.FALSE},
               {new Date(), "C", new Integer(9), Boolean.TRUE },
               {new Date(), "D", new Integer(4), Boolean.FALSE}
          JTable table = new JTable(data, columnNames)
               //  Returning the Class of each column will allow different
               //  renderers to be used based on Class
               public Class getColumnClass(int column)
                    return getValueAt(0, column).getClass();
          table.setPreferredScrollableViewportSize(table.getPreferredSize());
          JScrollPane scrollPane = new JScrollPane( table );
          getContentPane().add( scrollPane );
     public static void main(String[] args)
          TableBasic frame = new TableBasic();
          frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
          frame.pack();
          frame.setLocationRelativeTo( null );
          frame.setVisible(true);
}The default renderer for boolean values uses a JCheckBox to render the value. the check box uses setBorderPainted(false), which is why "focus rectangle" is not painted. Personally, I think this is a bug.
Anyway, if you want the "focus rectangle" then you would need to create your own Boolean renderer, setBorderPainted(true) and provide a default EmptyBorder for the check box:
Border noFocusBorder = new EmptyBorder(1, 1, 1, 1);