Why does the scroll disapear?

Question

Hello,
The initial state of this program is what I want.
But after I press on the "expand" / "collapse" the horizontal scroll disapears.
If I do manual resizing the scroll shows up.
What is wrong?
import javax.swing.*;
import javax.swing.table.AbstractTableModel;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
public class FixedColumnExample extends JFrame {
    Object[][] data;
    JTable[] tables = new JTable[3];
    JPanel panel = new JPanel() {
        public Dimension getPreferredSize() {
            //Dimension dimension = super.getPreferredSize();
            double height=0;
            double width=0;
            for (int i =0; i < getComponentCount(); i++){
                height += getComponent(i).getPreferredSize().getHeight();
                width = Math.max(width, getComponent(i).getPreferredSize().getWidth());
            return new Dimension((int)width, (int)height);
    public FixedColumnExample() {
        super("Fixed Column Example");
        setSize(400, 200);
        data = new Object[][]{{"1", "11", "A", "1", "1", "1", "1", "1"},
                {"2", "22", "2", "B", "2", "2", "2", "2"},
                {"3", "33", "3", "3", "C", "3", "3", "3"},
                {"4", "44", "4", "4", "4", "D", "4", "4"},
                {"5", "55", "5", "5", "5", "5", "E", "5"},
                {"6", "66", "6", "6", "6", "6", "6", "F"}};
        panel.setLayout(new BoxLayout(panel, BoxLayout.PAGE_AXIS));
        for (int i = tables.length - 1; i >= 0; i--) {
            addTable(i);
        adjustTablesWidth();
        getContentPane().add(panel);
        pack();
    public void pack() {
        super.pack();    //To change body of overridden methods use File | Settings | File Templates.
        setSize(500, (int) getSize().getHeight());
    private void addTable(final int currTable) {
        AbstractTableModel fixedModel = new AbstractTableModel() {
            public int getColumnCount() {
                return 2;
            public int getRowCount() {
                return data.length - currTable;
            public Object getValueAt(int row, int col) {
                return data[row][col];
        AbstractTableModel model = new AbstractTableModel() {
            public int getColumnCount() {
                return data[0].length - 2 - currTable;
            public int getRowCount() {
                return data.length - currTable;
            public Object getValueAt(int row, int col) {
                return data[row][col + 2];
            public void setValueAt(Object obj, int row, int col) {
                data[row][col + 2] = obj;
            public boolean CellEditable(int row, int col) {
                return true;
        tables[currTable] = new JTable(model) {
            public Dimension getPreferredScrollableViewportSize() {
                Dimension dimension = super.getPreferredSize();
                //System.out.println("table - " + dimension.getWidth());
                return dimension;
        tables[currTable].setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
        tables[currTable].setTableHeader(null);
        JScrollPane scroll = new JScrollPane(tables[currTable]) {
            public Dimension getPreferredSize() {
                Dimension dimension = super.getPreferredSize();
                dimension.setSize(dimension.getWidth(), dimension.getHeight() + getHorizontalScrollBar().getPreferredSize().getHeight());
                //System.out.println("scroll - " + dimension.getWidth());
                return dimension;
        JViewport viewport = new JViewport();
        JTable fixedTable = new JTable(fixedModel);
        fixedTable.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
        viewport.setView(fixedTable);
        viewport.setPreferredSize(fixedTable.getPreferredSize());
        scroll.setRowHeaderView(viewport);
        JPanel content = new JPanel();
        content.setLayout(new BoxLayout(content, BoxLayout.PAGE_AXIS));
        content.add(scroll);
        panel.add(new CollapsiblePanel(content, this));
    private void adjustTablesWidth() {
        int result = getMaxTableWidth();
        for (int i = 0; i < tables.length; i++)
            if (result != (int) tables.getPreferredSize().getWidth())
tables[i].setPreferredSize(new Dimension(result, (int) tables[i].getPreferredSize().getHeight()));
private int getMaxTableWidth() {
int result = 0;
for (int i = 0; i < tables.length; i++) {
result = Math.max(result, (int) tables[i].getPreferredSize().getWidth());
return result;
public static void main(String[] args) {
FixedColumnExample frame = new FixedColumnExample();
frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
frame.setVisible(true);
public class CollapseButton extends JButton implements ActionListener {
private Collapsible _collapsible;
public CollapseButton(Collapsible collapsible, int orientation) {
super();
_collapsible = collapsible;
setRolloverEnabled(true);
setFocusPainted(false);
setDefaultCapable(false);
setBorder(null);
setBorderPainted(false);
setMargin(new Insets(0, 0, 0, 0));
setToolTipText("Collapses/Expands Panel");
if (orientation == SwingConstants.VERTICAL) {
setText("collapse ");
} else {
setText("expand ");
addActionListener(this);
public void actionPerformed(ActionEvent evt) {
if (_collapsible.isCollapsed())
_collapsible.expand();
else
_collapsible.collapse();
public class CollapsiblePanel extends JPanel implements Collapsible {
private boolean _collapsed = false;
private JPanel _content;
private JFrame containingFrame;
private CollapseButton _collapseHorizontalButton;
private CollapseButton _collapseVerticalButton;
public CollapsiblePanel(JPanel content, JFrame containingFrame) {
_content = content;
this.containingFrame = containingFrame;
// Set layout direction
setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
setBackground(Color.red);
_collapseHorizontalButton = new CollapseButton(this, SwingConstants.HORIZONTAL);
_collapseVerticalButton = new CollapseButton(this, SwingConstants.VERTICAL);
expand();
public boolean isCollapsed() {
return _collapsed;
public boolean isCollapsible() {
return collapsible;
* Collapses the panel.
public void collapse() {
setVisible(false);
removeAll();
add(_collapseHorizontalButton);
_collapsed = true;
revalidate();
containingFrame.pack();
setVisible(true);
* Uncollapses the panel.
public void expand() {
setVisible(false);
removeAll();
add(_collapseVerticalButton);
add(_content);
_collapsed = false;
revalidate();
containingFrame.pack();
setVisible(true);
public Dimension getPreferredSize() {
Dimension dimension = super.getPreferredSize();
if (isCollapsed()) {
dimension.setSize(containingFrame.getSize().getWidth(), dimension.getHeight());
} else {
return dimension;

Answer 1

I do my set size because I want a fixed width and variable height.
Sorry for not including the Collapsible, this is the full program.
import javax.swing.*;
import javax.swing.table.AbstractTableModel;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
public class FixedColumnExample extends JFrame {
    Object[][] data;
    JTable[] tables = new JTable[3];
    JPanel panel = new JPanel() {
        public Dimension getPreferredSize() {
            //Dimension dimension = super.getPreferredSize();
            double height = 0;
            double width = 0;
            for (int i = 0; i < getComponentCount(); i++) {
                height += getComponent(i).getPreferredSize().getHeight();
                width = Math.max(width, getComponent(i).getPreferredSize().getWidth());
            return new Dimension((int) width, (int) height);
    public FixedColumnExample() {
        super("Fixed Column Example");
        setSize(500, 200);
        data = new Object[][]{{"1", "11", "A", "1", "1", "1", "1", "1"},
                {"2", "22", "2", "B", "2", "2", "2", "2"},
                {"3", "33", "3", "3", "C", "3", "3", "3"},
                {"4", "44", "4", "4", "4", "D", "4", "4"},
                {"5", "55", "5", "5", "5", "5", "E", "5"},
                {"6", "66", "6", "6", "6", "6", "6", "F"}};
        panel.setLayout(new BoxLayout(panel, BoxLayout.PAGE_AXIS));
        for (int i = tables.length - 1; i >= 0; i--) {
            addTable(i);
        adjustTablesWidth();
        getContentPane().add(panel);
        pack();
    public void pack() {
        super.pack();    //To change body of overridden methods use File | Settings | File Templates.
        setSize(500, (int) getSize().getHeight());
    private void addTable(final int currTable) {
        AbstractTableModel fixedModel = new AbstractTableModel() {
            public int getColumnCount() {
                return 2;
            public int getRowCount() {
                return data.length - currTable;
            public Object getValueAt(int row, int col) {
                return data[row][col];
        AbstractTableModel model = new AbstractTableModel() {
            public int getColumnCount() {
                return data[0].length - 2 - currTable;
            public int getRowCount() {
                return data.length - currTable;
            public Object getValueAt(int row, int col) {
                return data[row][col + 2];
            public void setValueAt(Object obj, int row, int col) {
                data[row][col + 2] = obj;
            public boolean CellEditable(int row, int col) {
                return true;
        tables[currTable] = new JTable(model) {
            public Dimension getPreferredScrollableViewportSize() {
                Dimension dimension = super.getPreferredSize();
                //System.out.println("table - " + dimension.getWidth());
                return dimension;
        tables[currTable].setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
        tables[currTable].setTableHeader(null);
        JScrollPane scroll = new JScrollPane(tables[currTable]) {
            public Dimension getPreferredSize() {
                Dimension dimension = super.getPreferredSize();
                dimension.setSize(dimension.getWidth(), dimension.getHeight() + getHorizontalScrollBar().getPreferredSize().getHeight());
                //System.out.println("scroll - " + dimension.getWidth());
                return dimension;
        JViewport viewport = new JViewport();
        JTable fixedTable = new JTable(fixedModel);
        fixedTable.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
        viewport.setView(fixedTable);
        viewport.setPreferredSize(fixedTable.getPreferredSize());
        scroll.setRowHeaderView(viewport);
        JPanel content = new JPanel();
        content.setLayout(new BoxLayout(content, BoxLayout.PAGE_AXIS));
        content.add(scroll);
        panel.add(new CollapsiblePanel(content, this));
    private void adjustTablesWidth() {
        int result = getMaxTableWidth();
        for (int i = 0; i < tables.length; i++)
            if (result != (int) tables.getPreferredSize().getWidth())
tables[i].setPreferredSize(new Dimension(result, (int) tables[i].getPreferredSize().getHeight()));
private int getMaxTableWidth() {
int result = 0;
for (int i = 0; i < tables.length; i++) {
result = Math.max(result, (int) tables[i].getPreferredSize().getWidth());
return result;
public static void main(String[] args) {
FixedColumnExample frame = new FixedColumnExample();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
/*frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
frame.setVisible(true);
public class CollapseButton extends JButton implements ActionListener {
private Collapsible _collapsible;
public CollapseButton(Collapsible collapsible, int orientation) {
super();
_collapsible = collapsible;
setRolloverEnabled(true);
setFocusPainted(false);
setDefaultCapable(false);
setBorder(null);
setBorderPainted(false);
setMargin(new Insets(0, 0, 0, 0));
setToolTipText("Collapses/Expands Panel");
if (orientation == SwingConstants.VERTICAL) {
setText("collapse ");
} else {
setText("expand ");
addActionListener(this);
public void actionPerformed(ActionEvent evt) {
if (_collapsible.isCollapsed())
_collapsible.expand();
else
_collapsible.collapse();
public class CollapsiblePanel extends JPanel implements Collapsible {
private boolean _collapsed = false;
private JPanel _content;
private JFrame containingFrame;
private CollapseButton _collapseHorizontalButton;
private CollapseButton _collapseVerticalButton;
public CollapsiblePanel(JPanel content, JFrame containingFrame) {
_content = content;
this.containingFrame = containingFrame;
// Set layout direction
setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
setBackground(Color.red);
_collapseHorizontalButton = new CollapseButton(this, SwingConstants.HORIZONTAL);
_collapseVerticalButton = new CollapseButton(this, SwingConstants.VERTICAL);
expand();
public boolean isCollapsed() {
return _collapsed;
public boolean isCollapsible() {
return collapsible;
* Collapses the panel.
public void collapse() {
setVisible(false);
removeAll();
add(_collapseHorizontalButton);
_collapsed = true;
revalidate();
containingFrame.pack();
setVisible(true);
* Uncollapses the panel.
public void expand() {
setVisible(false);
removeAll();
add(_collapseVerticalButton);
add(_content);
_collapsed = false;
revalidate();
containingFrame.pack();
setVisible(true);
public Dimension getPreferredSize() {
Dimension dimension = super.getPreferredSize();
if (isCollapsed()) {
dimension.setSize(containingFrame.getSize().getWidth(), dimension.getHeight());
} else {
return dimension;
public interface Collapsible {
final boolean collapsible = true;
public void collapse();
public void expand();
public boolean isCollapsible();
public boolean isCollapsed();