How to reset JTable column arrows

Question

I'm using sortable columns for my JTable:

table.setAutoCreateRowSorter(true);

The issue is that after the user click on a column header there's no way to remove the arrow. Even If I delete all the rows in the table.

I tried to do the opposite but it didn't work:

table.setAutoCreateRowSorter(false);

Answer 1

The fact the arrow is not removed seem to be a painting issue. Calling table.getTableHeader().repaint() seems to make the arrow go away.

Full example:

public class JTableSortRestore {
    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> {
            runGui();
        });
    }

    private static void runGui() {
        JFrame frame = new JFrame("");
        frame.setLayout(new BorderLayout());

        DefaultTableModel model = new DefaultTableModel();
        model.addColumn("Col");
        model.addRow(new String[] { "BBB" });
        model.addRow(new String[] { "AAA" });
        model.addRow(new String[] { "CCC" });
        JTable table = new JTable(model);
        table.setAutoCreateRowSorter(true);

        frame.add(new JScrollPane(table));

        JButton restoreButton = new JButton("Restore sorting");
        restoreButton.addActionListener(e -> {
            table.setAutoCreateRowSorter(false);

            table.setAutoCreateRowSorter(true);
            table.getTableHeader().repaint();
        });

        frame.add(restoreButton, BorderLayout.PAGE_END);

        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }
}