Displaying Image to Column Header,Setting Icon to Column Head,Setting an Icon with Text in a Column Head of JTable

Setting an Icon with Text in a Column Head of JTable

In this section, you will learn how to set an icon with text in a column head of JTable component. But what is icon?

Icon: This is a graphical user interface (GUI). An image or picture available on the screen that helps you to identify file, folder, directory and window etc.

Description of program:

First of all this program creates a JTable containing some data and column with column header. After that you will set the icons in column header. For this you will need an image or icon that have '.gif' extension. Here you will see the SetIcon method applied for setting the icon with text in column header. This method uses the setHeaderRenderer and setHeaderValue methods that helps you setting the icon and text in column header. After doing entire process, you will get the first and second column header having icon with text.

Description of code:

setText():
This is the method that is used to set the given text in specified location.

setIcon():
This method helps you to set the given icon on the specified location.

Here is the code of program:


import javax.swing.*;

import javax.swing.table.*;

import java.awt.*;



public class IconColumnHeader{

  JTable table;

  JTableHeader header;

  ImageIcon imageIcon;

  public static void main(String[] args) {

    new IconColumnHeader();

  }



  public IconColumnHeader(){

    JFrame frame = new JFrame("An Icon in a Column Head of a JTable!");

    JPanel panel = new JPanel();

    String data[][] = {{"Vinod","Computer","3"},

                      
{"Rahul","History","2"},

                      
{"Manoj","Biology","4"},

                      
{"Sanjay","PSD","5"}};

    String col [] = {"Name","Course","Year"};

    DefaultTableModel model = new DefaultTableModel(data,col);

    table = new JTable(model);

    imageIcon = new ImageIcon("bt_home.gif");

    SetIcon(table, 1, imageIcon,"Home");

    imageIcon = new ImageIcon("icon_evil.gif");

    SetIcon(table, 0, imageIcon,"Name");

    header = table.getTableHeader();

    header.setBackground(Color.yellow);

    JScrollPane pane = new JScrollPane(table);

    panel.add(pane);

    frame.add(panel);

    frame.setSize(500,150);

    frame.setUndecorated(true);

    frame.getRootPane().setWindowDecorationStyle(JRootPane.PLAIN_DIALOG);

    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    frame.setVisible(true);

  }



  public void SetIcon(JTable table, int col_index, ImageIcon icon,String name){

    table.getTableHeader().getColumnModel().getColumn(col_index).setHeaderRenderer

(new iconRenderer());

    table.getColumnModel().getColumn(col_index).setHeaderValue(new txtIcon(name, icon));

  }

  

  public class iconRenderer extends DefaultTableCellRenderer{

        public Component getTableCellRendererComponent(JTable table, 

Object obj,boolean isSelected, boolean hasFocus, int row, int column) {

      txtIcon i = (txtIcon)obj;

            if (obj == i) {

               setIcon(i.imageIcon);

               setText(i.txt);

            }

            setBorder(UIManager.getBorder("TableHeader.cellBorder"));

            setHorizontalAlignment(JLabel.CENTER);

            return this;

        }

    }



  public class txtIcon {

    String txt;

    ImageIcon imageIcon;

    txtIcon(String text, ImageIcon icon) {

      txt = text;

            imageIcon = icon;

        }

  }

}

Output of program:

Before setting an icon:

After setting an icon with text: