Change background color of JTable row based on column value

Question

hi i am new in java jtable cellrendered. I am looking for a way that works in my program but i dont have any luck finding it. Here is my Jtable

Employee ID   |   Name     |   Status    |   Position
  00565651        Roger       Active        Manager
  00565652        Gina        Active        Crew
  00565652        Alex        Inactive      Crew
  00565652        Seph        Active        Manager    

the data came from ms access database but i want to change the background/foreground of the rows which has a value of "inactive" in status column. I found many examples in the internet but all of it is not possible in my program. Can someone help me? This is my model

String[] columnNames = {"Employee ID","Name", "Status", "Position"};
DefaultTableModel model = new DefaultTableModel(columnNames, 0);

and this is the way to create my table and how i am fetching data from database

public MyList(){//my constructor
    frame();
    loadListFromDB();
}
public void frame(){//
   //codes for frame setsize,titles etc...
   tblList = new JTable();
   tblList.getTableHeader().setPreferredSize(new Dimension(100, 40));
   tblList.getTableHeader().setFont(new Font("SansSerif", Font.BOLD, 25));
   tblList.setAutoCreateRowSorter(true);
   tblList.setModel(model);
   scrollPane.setViewportView(tblList);
   loadListFromDB();

}
public void loadListFromDB(){
   String sql = "SELECT emp_id,lname,fname,positional_status from tblEmployee";
    try{
        PreparedStatement ps = conn.prepareStatement(sql);
        ResultSet rs = ps.executeQuery();
        while (rs.next()){
            Vector row = new Vector();
            for (int i = 1; i <= 4; i++){
                row.addElement( rs.getObject(i) );
            }
            model.addRow(row);
        }
    }catch(Exception err){
        //for error code
    }
}

How am i suppose to add the tableredered in this way?Can anyone give simple example to change the color of row? Thanks in advance.. My program stop in this problem.

Solution

"i want to change the background/foreground of the rows which has a value of "inactive" in status column"

It's really just a matter of getting the value from table/model. if the status for that row is inactive, then set the background/foreground for every every cell in that row. Since the renderer is rendered for every cell, then basically you need to get the value of the [row][statusColumn], and that will be the status value for each row. Something like

table.setDefaultRenderer(Object.class, new DefaultTableCellRenderer(){
    @Override
    public Component getTableCellRendererComponent(JTable table,
            Object value, boolean isSelected, boolean hasFocus, int row, int col) {

        super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, col);

        String status = (String)table.getModel().getValueAt(row, STATUS_COL);
        if ("active".equals(status)) {
            setBackground(Color.BLACK);
            setForeground(Color.WHITE);
        } else {
            setBackground(table.getBackground());
            setForeground(table.getForeground());
        }       
        return this;
    }   
});

Here's a simple example

import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;

import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.DefaultTableModel;

public class TableRowDemo {

    private static final int STATUS_COL = 1;

    private static JTable getTable() {
        final String[] cols = {"col 1", "status", "col 3"};
        final String[][] data = {
                {"data", "active", "data"},
                {"data", "inactive", "data"},
                {"data", "inactive", "data"},
                {"data", "active", "data"}
        };
        DefaultTableModel model = new DefaultTableModel(data, cols);
        return new JTable(model) {
            @Override
            public Dimension getPreferredScrollableViewportSize() {
                return new Dimension(350, 150);
            }
        };
    }

    private static JTable getNewRenderedTable(final JTable table) {
        table.setDefaultRenderer(Object.class, new DefaultTableCellRenderer(){
            @Override
            public Component getTableCellRendererComponent(JTable table,
                    Object value, boolean isSelected, boolean hasFocus, int row, int col) {
                super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, col);
                String status = (String)table.getModel().getValueAt(row, STATUS_COL);
                if ("active".equals(status)) {
                    setBackground(Color.BLACK);
                    setForeground(Color.WHITE);
                } else {
                    setBackground(table.getBackground());
                    setForeground(table.getForeground());
                }       
                return this;
            }   
        });
        return table;
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable(){
            public void run() {
                JOptionPane.showMessageDialog(null, new JScrollPane(getNewRenderedTable(getTable())));
            }
        });
    }
}

Another option is to @Override prepareRenderer of the table. It will give you the same result.

import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;

import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableCellRenderer;

public class TableRowDemo {

    private static final int STATUS_COL = 1;

    private static JTable getTable() {
        final String[] cols = {"col 1", "status", "col 3"};
        final String[][] data = {
                {"data", "active", "data"},
                {"data", "inactive", "data"},
                {"data", "inactive", "data"},
                {"data", "active", "data"}
        };
        DefaultTableModel model = new DefaultTableModel(data, cols);
        return new JTable(model) {
            @Override
            public Dimension getPreferredScrollableViewportSize() {
                return new Dimension(350, 150);
            }
            @Override
            public Component prepareRenderer(TableCellRenderer renderer, int row, int col) {
                Component c = super.prepareRenderer(renderer, row, col);
                String status = (String)getValueAt(row, STATUS_COL);
                if ("active".equals(status)) {
                    c.setBackground(Color.BLACK);
                    c.setForeground(Color.WHITE);
                } else {
                    c.setBackground(super.getBackground());
                    c.setForeground(super.getForeground());
                }
                return c;
            }
        };
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable(){
            public void run() {
                JOptionPane.showMessageDialog(null, new JScrollPane(getTable()));
            }
        });
    }
}

Comments

[Mohammed Mohammed]

Great answer I was looking for that. can we change the Table's Headers Style at the same time?

[Aequitas]

@peeskillet how can the prepare renderer method be modified to change the column instead of the row's background colour?

[Amr Saber]

@peeskillet when I used your code, the selection of my table changed; it was set to select row now it selects a cell, also the color of the selected cell changed, not the default color anymore

[Hachachin]

i get Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at the line of getting the value of row, String entry = (String) table.getModel().getValueAt(row, 2), any help please, thanks.

[Candamir]

In the getTableCellRendererComponent method, does it make a difference whether I (a) simply invoke super.getTableCellRendererComponent and then make my format changes by invoking methods of super or this and then return this (as this answer does) or (b) declare a new Component x = super.getTableCellRendererComponent and then make the format changes to x and return x?