Change the background color of a row in a JTable

Question

I have a JTable with 3 columns  I ve set the TableCellRenderer for all the 3 columns like this  maybe not very effective      for  int i   0  i  lt  3  i           myJTable getColumnModel   getColumn i  setCellRenderer renderer        The getTableCellRendererComponent   returns a Component with a random background color for each row  How could I change the background to an other random color while the program is running

User · Answer

The call to getTableCellRendererComponent      includes the value of the cell for which a renderer is sought    You can use that value to compute a color  If you re also using an AbstractTableModel  you can provide a value of arbitrary type to your renderer   Once you have a color  you can setBackground   on the component that you re returning

User · Answer

This is basically as simple as repainting the table   I haven t found a way to selectively repaint just one row column cell however   In this example  clicking on the button changes the background color for a row and then calls repaint   public class TableTest       public static void main String   args            JFrame frame   new JFrame            frame setDefaultCloseOperation JFrame EXIT ON CLOSE            final Color   rowColors   new Color                     randomColor    randomColor    randomColor                      final JTable table   new JTable 3  3           table setDefaultRenderer Object class  new TableCellRenderer                  Override             public Component getTableCellRendererComponent JTable table                      Object value  boolean isSelected  boolean hasFocus                      int row  int column                    JPanel pane   new JPanel                    pane setBackground rowColors row                    return pane                                    frame setLayout new BorderLayout              JButton btn   new JButton  Change row2 s color            btn addActionListener new ActionListener                 public void actionPerformed ActionEvent e                    rowColors 1    randomColor                    table repaint                                       frame add table  BorderLayout NORTH           frame add btn  BorderLayout SOUTH           frame pack            frame setVisible true              private static Color randomColor             Random rnd   new Random            return new Color rnd nextInt 256                   rnd nextInt 256   rnd nextInt 256

User · Answer

One way would be store the current colour for each row within the model  Here s a simple model that is fixed at 3 columns and 3 rows   static class MyTableModel extends DefaultTableModel        List lt Color gt  rowColours   Arrays asList          Color RED          Color GREEN          Color CYAN             public void setRowColour int row  Color c            rowColours set row  c           fireTableRowsUpdated row  row              public Color getRowColour int row            return rowColours get row               Override     public int getRowCount             return 3              Override     public int getColumnCount             return 3              Override     public Object getValueAt int row  int column            return String format   d  d   row  column             Note that setRowColour calls fireTableRowsUpdated  this will cause just that row of the table to be updated   The renderer can get the model from the table   static class MyTableCellRenderer extends DefaultTableCellRenderer         Override     public Component getTableCellRendererComponent JTable table  Object value  boolean isSelected  boolean hasFocus  int row  int column            MyTableModel model    MyTableModel  table getModel            Component c   super getTableCellRendererComponent table  value  isSelected  hasFocus  row  column           c setBackground model getRowColour row            return c            Changing a row s colour would be as simple as   model setRowColour 1  Color YELLOW

User · Answer

The other answers given here work well since you use the same renderer in every column   However  I tend to believe that generally when using a JTable you will have different types of data in each columm and therefore you won t be using the same renderer for each column  In these cases you may find the Table Row Rendering approach helpfull

User · Answer

Resumee of Richard Fearn s answer   to make each second line gray   jTable setDefaultRenderer Object class  new DefaultTableCellRenderer          Override     public Component getTableCellRendererComponent JTable table  Object value  boolean isSelected  boolean hasFocus  int row  int column                final Component c   super getTableCellRendererComponent table  value  isSelected  hasFocus  row  column           c setBackground row   2    0   Color LIGHT GRAY   Color WHITE           return c

[java] Change the background color of a row in a JTable

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