Java Swing table coloring

[Aeren]

Hi everyone!

I would like to know if it's possible, to change the color(for- or background) of one cell.
Anyone ever tried that before?

 

[bassman]

Derive a from DefaultTableCellRenderer and override getTableCellRendererComponent().

class MyTableCellRenderer extends DefaultTableCellRenderer
{
  public Component getTableCellRendererComponent(JTable table,
    Object value, boolean isSelected,boolean hasFocus,int row, int col)
  {
    Component comp = super.getTableCellRendererComponent(table,
      value, isSelected, hasFocus, row, col);

    setBackground(/*color*/);

    return comp;
  }
}

Set the renderer using JTable.setDefaultRenderer().

 

[Aeren]

Derive a from DefaultTableCellRenderer and override getTableCellRendererComponent().

class MyTableCellRenderer extends DefaultTableCellRenderer
{
  public Component getTableCellRendererComponent(JTable table,
    Object value, boolean isSelected,boolean hasFocus,int row, int col)
  {
    Component comp = super.getTableCellRendererComponent(table,
      value, isSelected, hasFocus, row, col);

    setBackground(/*color*/);

    return comp;
  }
}

Set the renderer using JTable.setDefaultRenderer().

What can i do if i already extend from JFrame?
This is my code so far.

import java.util.*;
import java.util.Vector.*;
import javax.swing.*;
import javax.swing.table.*;
import java.awt.GridLayout;
import java.awt.Dimension;

public class View extends JFrame {
  private JFrame myFrame;
  private JTabbedPane tabbedPane;
  private JTable myTable;
  private JScrollPane scrollPane;

  public View( int size ) {
    super("Changes");
    try {
      UIManager.setLookAndFeel(
      UIManager.getSystemLookAndFeelClassName( ) );
    } catch ( Exception e ) { System.out.println( e.getMessage( ) ); }
    myTable = new JTable( size, 2 );
    myTable.setRowHeight( 20 );
    scrollPane = new JScrollPane( myTable, ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED, ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED );
    scrollPane.setPreferredSize( new Dimension( 640, 480 ) );
  }

  public void addLine( String whichSide, int whichRow, String content ) {
    if( whichSide.equals( "source" ) ) {
      myTable.setValueAt( content,whichRow ,0 );
    } else {
      myTable.setValueAt( content,whichRow ,1 );
    }
  }

  public void showAll( ) {
    this.getContentPane( ).add( scrollPane );
    this.setSize( 640,480 );
    this.setLocationRelativeTo( null );
    this.setDefaultCloseOperation( JFrame.DISPOSE_ON_CLOSE );
    this.setVisible( true );
  }

}

The function addLine should be the one to set the color to green. How can i do that?

Thanks
Aeren

 

[bassman]

Having an external method (addLine) is not the way to do this. JTable colors each cell when it is rendered. By using an overridden DefaultTableCellRenderer, you hook directly in to the cell rendering in a nice, encapsulated, object-oriented way.

 

[Aeren]

Having an external method (addLine) is not the way to do this. JTable colors each cell when it is rendered. By using an overridden DefaultTableCellRenderer, you hook directly in to the cell rendering in a nice, encapsulated, object-oriented way.

Ok, i have another problem then:
Unlike List, the size of JTable can't be changed after it's constructed(at least i didn't find a way to do it). The function addLine only writes in a cell, "Line" only indicates that i write in a line of information. I have to make my program in MVC model, and this is the View part. The information is in Model, that's why i'm having this function to transfer the information.

 

[bassman]

So should the cells be colored differently based on their value?