How to Display Row Header on JTable Instead of Column Header
This is a proof of concept only
Disclaimer: Before I get a bunch of hate mail about the, obviously, horrible things I've done to make this work, I stole most of the painting code straight out of the source, this is how it's actually done within the look and feel code itself :P
I've also gone to the nth degree, meaning that I've literally assumed that you wanted the row headers to look like the column headers. If this isn't a requirement, it would be SO much easier to do...
Okay, this is a basic proof of concept, which provides the means to generate the row header and render them the same way as they are normally, just as row headers instead.
Things that need to be added/supported:
Detect when the table model is changed (that is, a new table model is set to the table)
Detect when the column model is changed (that is, a new column model is set to the table)
Much of this functionality would probably need to be added to the TableWithRowHeader implementation...
Basically, what this "tries" to do, is create a custom row header, based on a JTableHeader, remove the existing column header and add itself into the row header view position of the enclosing JScrollPane.
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagConstraints;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JViewport;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
import javax.swing.event.TableColumnModelEvent;
import javax.swing.event.TableColumnModelListener;
import javax.swing.table.DefaultTableColumnModel;
import javax.swing.table.JTableHeader;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableColumn;
import javax.swing.table.TableColumnModel;
public class TableRowHeaderTest {
public static void main(String[] args) {
new TableRowHeaderTest();
}
public TableRowHeaderTest() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
Object rowData1[][]
= {
{"", "", "", ""},
{"", "", "", ""},
{"", "", "", ""},
{"", "", "", ""}
};
Object columnNames1[] = {"HEADER 1", "HEADER 2", "HEADER 3", "HEADER 4"};
JTable table1 = new TableWithRowHeader(rowData1, columnNames1);
table1.getColumnModel().getColumn(0).setPreferredWidth(120);
JScrollPane scrollPane1 = new JScrollPane(table1);
scrollPane1.setColumnHeaderView(null);
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(scrollPane1);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TableWithRowHeader extends JTable {
private TableRowHeader rowHeader;
public TableWithRowHeader(final Object[][] rowData, final Object[] columnNames) {
super(rowData, columnNames);
rowHeader = new TableRowHeader(this);
}
@Override
protected void configureEnclosingScrollPane() {
// This is required as it calls a private method...
super.configureEnclosingScrollPane();
Container parent = SwingUtilities.getUnwrappedParent(this);
if (parent instanceof JViewport) {
JViewport port = (JViewport) parent;
Container gp = port.getParent();
if (gp instanceof JScrollPane) {
JScrollPane scrollPane = (JScrollPane) gp;
JViewport viewport = scrollPane.getViewport();
if (viewport == null || SwingUtilities.getUnwrappedView(viewport) != this) {
return;
}
scrollPane.setColumnHeaderView(null);
scrollPane.setRowHeaderView(rowHeader);
}
}
}
}
public class TableRowHeader extends JTableHeader {
private JTable table;
public TableRowHeader(JTable table) {
super(table.getColumnModel());
this.table = table;
table.getColumnModel().addColumnModelListener(new TableColumnModelListener() {
@Override
public void columnAdded(TableColumnModelEvent e) {
repaint();
}
@Override
public void columnRemoved(TableColumnModelEvent e) {
repaint();
}
@Override
public void columnMoved(TableColumnModelEvent e) {
repaint();
}
@Override
public void columnMarginChanged(ChangeEvent e) {
repaint();
}
@Override
public void columnSelectionChanged(ListSelectionEvent e) {
// Don't care about this, want to highlight the row...
}
});
table.getSelectionModel().addListSelectionListener(new ListSelectionListener() {
@Override
public void valueChanged(ListSelectionEvent e) {
repaint();
}
});
}
public JTable getTable() {
return table;
}
@Override
public Dimension getPreferredSize() {
Dimension size = new Dimension();
JTable table = getTable();
if (table != null) {
TableColumnModel model = table.getColumnModel();
if (model != null) {
for (int index = 0; index < model.getColumnCount(); index++) {
TableColumn column = model.getColumn(index);
TableCellRenderer renderer = column.getHeaderRenderer();
if (renderer == null) {
renderer = getDefaultRenderer();
}
Component comp = renderer.getTableCellRendererComponent(table, column.getHeaderValue(), false, false, -1, index);
size.width = Math.max(comp.getPreferredSize().width, size.width);
size.height += table.getRowHeight(index);
}
}
}
return size;
}
/**
* Overridden to avoid propagating a invalidate up the tree when the
* cell renderer child is configured.
*/
@Override
public void invalidate() {
}
/**
* If the specified component is already a child of this then we don't bother doing anything - stacking order doesn't matter for cell renderer components
* (CellRendererPane doesn't paint anyway).
*/
@Override
protected void addImpl(Component x, Object constraints, int index) {
if (x.getParent() == this) {
return;
} else {
super.addImpl(x, constraints, index);
}
}
@Override
protected void paintComponent(Graphics g) {
// super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
g2d.setColor(getBackground());
g2d.fillRect(0, 0, getWidth(), getHeight());
JTable table = getTable();
if (table != null) {
int width = getWidth();
TableColumnModel model = table.getColumnModel();
if (model != null) {
for (int index = 0; index < model.getColumnCount(); index++) {
TableColumn column = model.getColumn(index);
TableCellRenderer renderer = column.getHeaderRenderer();
if (renderer == null) {
renderer = getDefaultRenderer();
}
boolean selected = table.getSelectedRow() == index;
Component comp = renderer.getTableCellRendererComponent(table, column.getHeaderValue(), selected, false, 0, index);
add(comp);
comp.validate();
int height = table.getRowHeight(index) - 1;
comp.setBounds(0, 0, width, height);
comp.paint(g2d);
comp.setBounds(-width, -height, 0, 0);
g2d.setColor(table.getGridColor());
g2d.drawLine(0, height, width, height);
g2d.translate(0, height + 1);
}
}
}
g2d.dispose();
removeAll();
}
}
}
Disclaimer: This is likely to blow up in your face. I make no checks for preventing the header from responding to things like changes to the column row sortering and ... in theory ... it shouldn't try and "resize" the column but I didn't test that...
https://stackoverflow.com/questions/26248084/how-to-display-row-header-on-jtable-instead-of-column-header
java
·
Jan. 12, 2023, 1:36 a.m.