// Fig. 13.12: LookAndFeelDemo.java
// Changing the look and feel.

// Java core packages
import java.awt.*;
import java.awt.event.*;

// Java extension packages
import javax.swing.*;

public class LookAndFeelDemo extends JFrame {

   private String strings[] = { "Metal", "Motif", "Windows" };
   private UIManager.LookAndFeelInfo looks[];
   private JRadioButton radio[];
   private ButtonGroup group;
   private JButton button;
   private JLabel label;
   private JComboBox comboBox;

   // set up GUI
   public LookAndFeelDemo()
   {
      super( "Look and Feel Demo" );

      Container container = getContentPane();

      // set up panel for NORTH of BorderLayout
      JPanel northPanel = new JPanel();
      northPanel.setLayout( new GridLayout( 3, 1, 0, 5 ) );

      // set up label for NORTH panel
      label = new JLabel( "This is a Metal look-and-feel",
         SwingConstants.CENTER );
      northPanel.add( label );

      // set up button for NORTH panel
      button = new JButton( "JButton" );
      northPanel.add( button );

      // set up combo box for NORTH panel
      comboBox = new JComboBox( strings );
      northPanel.add( comboBox );
     
      // attach NORTH panel to content pane
      container.add( northPanel, BorderLayout.NORTH );

      // create array for radio buttons
      radio = new JRadioButton[ strings.length ];

      // set up panel for SOUTH of BorderLayout
      JPanel southPanel = new JPanel();
      southPanel.setLayout( 
         new GridLayout( 1, radio.length ) );

      // set up radio buttons for SOUTH panel
      radio = new JRadioButton[ strings.length ];
      group = new ButtonGroup();
      ItemHandler handler = new ItemHandler();

      for ( int count = 0; count < radio.length; count++ ) {
         radio[ count ] = new JRadioButton( strings[ count ] );
         radio[ count ].addItemListener( handler );
         group.add( radio[ count ] );
         southPanel.add( radio[ count ] );
      }

      // attach SOUTH panel to content pane
      container.add( southPanel, BorderLayout.SOUTH );

      // get installed look-and-feel information
      looks = UIManager.getInstalledLookAndFeels();

      setSize( 300, 200 );
      setVisible( true );

      radio[ 0 ].setSelected( true );
   }

   // use UIManager to change look-and-feel of GUI
   private void changeTheLookAndFeel( int value )
   {
      // change look and feel
      try {
         UIManager.setLookAndFeel(
            looks[ value ].getClassName() );
         SwingUtilities.updateComponentTreeUI( this );
      }

      // process problems changing look and feel
      catch ( Exception exception ) {
         exception.printStackTrace();
      }
   }

   // execute application
   public static void main( String args[] )
   {
      LookAndFeelDemo application = new LookAndFeelDemo();

      application.setDefaultCloseOperation(
         JFrame.EXIT_ON_CLOSE );
   }

   // private inner class to handle radio button events
   private class ItemHandler implements ItemListener {

      // process user's look-and-feel selection
      public void itemStateChanged( ItemEvent event )
      {
         for ( int count = 0; count < radio.length; count++ )

            if ( radio[ count ].isSelected() ) {
               label.setText( "This is a " +
                  strings[ count ] + " look-and-feel" );
               comboBox.setSelectedIndex( count );

               changeTheLookAndFeel( count );
            }
      }

   }  // end private inner class ItemHandler

}  // end class LookAndFeelDemo


/**************************************************************************
 * (C) Copyright 2002 by Deitel & Associates, Inc. and Prentice Hall.     *
 * All Rights Reserved.                                                   *
 *                                                                        *
 * DISCLAIMER: The authors and publisher of this book have used their     *
 * best efforts in preparing the book. These efforts include the          *
 * development, research, and testing of the theories and programs        *
 * to determine their effectiveness. The authors and publisher make       *
 * no warranty of any kind, expressed or implied, with regard to these    *
 * programs or to the documentation contained in these books. The authors *
 * and publisher shall not be liable in any event for incidental or       *
 * consequential damages in connection with, or arising out of, the       *
 * furnishing, performance, or use of these programs.                     *
 *************************************************************************/