JRadioButton

 

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

 

public class RadioButtonTest extends JFrame

  {

   private JTextField t;

   private Font plainFont, boldFont,

                italicFont, boldItalicFont;

   private JRadioButton plain, bold, italic, boldItalic;

   private ButtonGroup radioGroup;

 

   public RadioButtonTest()

   {

      super( "RadioButton Test" );

 

      Container c = getContentPane();

      c.setLayout( new FlowLayout() );

 

      t = new JTextField( "Watch the font style change", 25 );

      c.add( t );

 

      // Create radio buttons

      plain = new JRadioButton( "Plain", true );

      c.add( plain );

      bold = new JRadioButton( "Bold", false);

      c.add( bold );

      italic = new JRadioButton( "Italic", false );

      c.add( italic );

      boldItalic = new JRadioButton( "Bold/Italic", false );

      c.add( boldItalic );

 

      // register events

      RadioButtonHandler handler = new RadioButtonHandler();

      plain.addItemListener( handler );

      bold.addItemListener( handler );

      italic.addItemListener( handler );

      boldItalic.addItemListener( handler );

 

      // create logical relationship between JRadioButtons

      radioGroup = new ButtonGroup();

      radioGroup.add( plain );

      radioGroup.add( bold );

      radioGroup.add( italic );

      radioGroup.add( boldItalic );

 

      plainFont = new Font( "TimesRoman", Font.PLAIN, 14 );

      boldFont = new Font( "TimesRoman", Font.BOLD, 14 );

      italicFont = new Font( "TimesRoman", Font.ITALIC, 14 );

      boldItalicFont =

         new Font( "TimesRoman", Font.BOLD + Font.ITALIC, 14 );

      t.setFont( plainFont );

 

      setSize( 300, 100 );

      show();

   }

 

   public static void main( String args[] )

   {

      RadioButtonTest app = new RadioButtonTest();

 

      app.addWindowListener(

         new WindowAdapter()

        {

            public void windowClosing( WindowEvent e )

            {

               System.exit( 0 );

            }

         }

      );

   }

 

   private class RadioButtonHandler implements ItemListener

     {

      public void itemStateChanged( ItemEvent e )

      {

         if ( e.getSource() == plain )

            t.setFont( plainFont );

         else if ( e.getSource() == bold )

            t.setFont( boldFont );

         else if ( e.getSource() == italic )

            t.setFont( italicFont );

         else if ( e.getSource() == boldItalic )

            t.setFont( boldItalicFont );

 

         t.repaint();

      }

   }

}