Freeze Pane in JTable

[John Jai]

Hi,

I have a JTable that has many number of columns with the CheckBox at the first column of each row. I can delete / commit changes by selecting the check box at the the first column. Since my Jtable has many columns, users have to navigate to the far left to check the CheckBox after making modifications in the row.

Is there a Freeze Pane (as in Microsoft Excel) for columns concept in JTable? The JTable is in a scroll pane so if I move to the far right of the JTable will the check box first column also come along?

Note - I use CheckBoxRenderer to get the CheckBox in the first column.

Thanks,
John

[Darryl Burke]

You could try Rob Camick's Fixed Column Table.

[Arun Chidam]

Also you could customize your contentpane to add 2 Jtables, one with checkbox and 2nd Jtabel with rest of the columns, when you scroll your horizontal bar, capture the mouse click event and reset the coordinates for Jtable1 to be in a visiable area.....

Sounds more complicated then previous post...but this also resolves your issue.

[John Jai]

I tried Rob Camick's Fixed Column Table but ran to some issues.

1. Since my first column Header is rendered by CheckBoxRenderer. Now if I check CheckBox in the first column header currently it selects all the check box in the first column (its a Check All / Deselect All) Check Box. This functionality does not work if I integrate with FixedColumnTable code like below

		FixedColumnTable fixedColumnTable = new FixedColumnTable(1, resultScrollPane);

2. Some of the check boxes in the bottom go missing in the first column - Please see attached Screen Shot.

3. The first column goes till the scroll pane length and not stop with JTable's length - Please see attached Screen Shot.

I will try the second solution ( making 2 Jtables in my code) and let you know the results.

Thanks both of you for your replies.

[John Jai]

Hi,

I fixed the issues i ran while trying to implement Rob Camick's FixedColumnTable. My bad - the issues were due to my custom main table configurations & were rather easy to fix.

Ok now the stupid fixes -

1. Removed CheckBoxRenderer from my main table & gave it to the Fixed Table
2. Made the row height of both main table & Fixed Table to be the same. This ensures check box & other columns were in same line
3. Changed Fixed Table's Background to match the main table background + scrollpane background and thus the grey shade went away.

One more issue if faced & fixed ->
4. While sorting on the main table, the sort does not apply to the checkbox column in the Fixed Table. Solution is to assign the main table sorter to the Fixed Table Sorter.

Thanks to Darryl Bruke to lead me to the solution & Arun for giving an alternative.

I would like to leave the modified code here.

package com.wk.cat.ui;

import java.awt.Color;

import java.awt.Component;
import java.awt.Font;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

import javax.swing.AbstractButton;
import javax.swing.JCheckBox;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JViewport;
import javax.swing.UIManager;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import javax.swing.table.JTableHeader;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableColumn;
import javax.swing.table.TableColumnModel;


/*
 *  Prevent the specified number of columns from scrolling horizontally in
 *  the scroll pane. The table must already exist in the scroll pane.
 *
 *  The functionality is accomplished by creating a second JTable (fixed)
 *  that will share the TableModel and SelectionModel of the main table.
 *  This table will be used as the row header of the scroll pane.
 *
 *  The fixed table created can be accessed by using the getFixedTable()
 *  method. will be returned from this method. It will allow you to:
 *
 *  You can change the model of the main table and the change will be
 *  reflected in the fixed model. However, you cannot change the structure
 *  of the model.
 */
@SuppressWarnings("serial")
public class FixedColumnTable  implements ChangeListener, PropertyChangeListener, ItemListener
{
	private CheckBoxHeaderRenderer rendererComponent; 

	private JTable main;
	private JTable fixed;
	private JScrollPane scrollPane;

	/*
	 *  Specify the number of columns to be fixed and the scroll pane
	 *  containing the table.
	 */
	public FixedColumnTable(Color tableColor, int fixedColumns, JScrollPane scrollPane)
	{
		this.scrollPane = scrollPane;

		main = ((JTable)scrollPane.getViewport().getView());
//		main.setAutoCreateColumnsFromModel( false );
		main.addPropertyChangeListener(this);

		//  Use the existing table to create a new table sharing
		//  the DataModel and ListSelectionModel

//		int totalColumns = main.getColumnCount();

		fixed = new JTable();
		fixed.setAutoCreateColumnsFromModel( false );
		fixed.setModel( main.getModel() );
		fixed.setSelectionModel( main.getSelectionModel() );
		fixed.setFocusable( false );
		fixed.setBackground(tableColor);
		fixed.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
		fixed.setDragEnabled(false);
		fixed.getTableHeader().setReorderingAllowed(false);
		fixed.setFont(new Font("Tahoma",Font.PLAIN,12));
		fixed.setRowHeight(20);

		//  Remove the fixed columns from the main table
		//  and add them to the fixed table

		for (int i = 0; i < fixedColumns; i++)
		{
	        TableColumnModel columnModel = main.getColumnModel();
	        TableColumn column = columnModel.getColumn( 0 );
    	    columnModel.removeColumn( column );
			fixed.getColumnModel().addColumn( column );
		}
		
		TableColumn checkBoxColumn = fixed.getColumnModel().getColumn(0);  
		checkBoxColumn.setHeaderRenderer(new CheckBoxHeaderRenderer(this));			
		
		fixed.setRowSorter(main.getRowSorter());
		main.setUpdateSelectionOnSort(true);
		fixed.setUpdateSelectionOnSort(false);

		//  Add the fixed table to the scroll pane

        fixed.setPreferredScrollableViewportSize(fixed.getPreferredSize());
		scrollPane.setRowHeaderView( fixed );
		scrollPane.setCorner(JScrollPane.UPPER_LEFT_CORNER, fixed.getTableHeader());

		// Synchronize scrolling of the row header with the main table

		scrollPane.getRowHeader().addChangeListener( this );
	}

	/*
	 *  Return the table being used in the row header
	 */
	public JTable getFixedTable()
	{
		return fixed;
	}
//
//  Implement the ChangeListener
//
	public void stateChanged(ChangeEvent e)
	{
		//  Sync the scroll pane scrollbar with the row header

		JViewport viewport = (JViewport) e.getSource();
		scrollPane.getVerticalScrollBar().setValue(viewport.getViewPosition().y);
	}
//
//  Implement the PropertyChangeListener
//
	public void propertyChange(PropertyChangeEvent e)
	{
		//  Keep the fixed table in sync with the main table

		if ("selectionModel".equals(e.getPropertyName()))
		{
			fixed.setSelectionModel( main.getSelectionModel() );
		}

		if ("model".equals(e.getPropertyName()))
		{
			fixed.setModel( main.getModel() );
		}
	}
	
	/**
	 * This is the Check Box Renderer class that provides the Select All CheckBox Renderer for the Table
	 *
	 */
	class CheckBoxHeaderRenderer extends JCheckBox implements TableCellRenderer, MouseListener {     
		protected int column;     
		protected boolean mousePressed = false;    
		ItemListener it1;
		
		/**
		 * Constructor method that sets the ItemListener for ItemState changed events 
		 * @param itemListener
		 */
		public CheckBoxHeaderRenderer(ItemListener itemListener) {     
			setRendererComponent(this);  
			this.it1 = itemListener;  
			rendererComponent.addItemListener(it1);     
		}     
		
		/**
		 * This is the Renderer method that returns the rendering component
		 */
		public Component getTableCellRendererComponent(JTable table, Object value,boolean isSelected, boolean hasFocus, int row, int column) {  
			if (table != null) {     
				JTableHeader header = table.getTableHeader();    
				if (header != null) {     
					rendererComponent.setForeground(header.getForeground());     
					rendererComponent.setBackground(header.getBackground());     
					rendererComponent.setFont(header.getFont());  
					header.addMouseListener(rendererComponent);     
				}     
			}     
			setColumn(column);     
			setBorder(UIManager.getBorder("TableHeader.cellBorder"));     
			return rendererComponent;     
		}     
		protected void setColumn(int column) {     
			this.column = column;     
		}     
		public int getColumn() {     
			return column;     
		}     
		protected void handleClickEvent(MouseEvent e) {     
			if (mousePressed) {  
				mousePressed=false;           
				JTableHeader header = (JTableHeader)(e.getSource());     
				JTable tableView = header.getTable();     
				TableColumnModel columnModel = tableView.getColumnModel();     
				int viewColumn = columnModel.getColumnIndexAtX(e.getX());     
				int column = tableView.convertColumnIndexToModel(viewColumn);     
				if (viewColumn == this.column && e.getClickCount() == 1 && column != -1) {     
					doClick();     
				}   
			}     
		}     
		public void mouseClicked(MouseEvent e) {     
			handleClickEvent(e);     
			//((JTableHeader)e.getSource()).repaint();     
		}     
		public void mousePressed(MouseEvent e) {     
			mousePressed = true;     
		}     
		public void mouseReleased(MouseEvent e) {     
		}     
		public void mouseEntered(MouseEvent e) {     
		}     
		public void mouseExited(MouseEvent e) {     
		}   
	} 
	
	/**
	 * Getter method of the CheckBox Renderer component
	 * @return
	 */
	public CheckBoxHeaderRenderer getRendererComponent() {  
		return rendererComponent;  
	}  
	
	/**
	 * Sets the Renderer Component to CheckBoxHeaderRenderer
	 * @param rendererComponent
	 */
	public void setRendererComponent(CheckBoxHeaderRenderer rendererComponent) {  
		rendererComponent.setText("");  
		this.rendererComponent = rendererComponent;  
	}
	
	/**
	 * Item State Changed Event which is used to capture "Select All" Check Box Header selections
	 */
	public void itemStateChanged(ItemEvent e) {  
		Object source = e.getSource();  
		if (source instanceof AbstractButton == false) return;  
		if(source instanceof CheckBoxHeaderRenderer){
			boolean checked = e.getStateChange() == ItemEvent.SELECTED;			
			int column = ((CheckBoxHeaderRenderer)source).column;
			for(int x = 0, y = fixed.getRowCount(); x < y; x++)  
			{  
				fixed.setValueAt(new Boolean(checked),x,column);  
			}
			fixed.getTableHeader().repaint();
		}  
	}
	
}

[Sharad Kharya]

Hi, I found this post very useful as it met my requirements. But i am blocked only at one point.
Grey colour is not getting removed from my fixed Table.
I am attaching the screenshots. please let me know, how this can be achieved.

[Darryl Burke]

Try fixed.setFillsViewportHeight(true);

[Sharad Kharya]

Thanks it worked.
Just curious to know. can't the 1 horizontal scrollbar is viewable commonly in fixed + main table. And keep 1st column as fixed.