colormenuex3.java

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import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
class ColorMenuEx3 extends JFrame implements ActionListener {
   public ColorMenuEx3() {
      menuBar = new JMenuBar();
      colorMenu = new JMenu( "Colors" );
      controls = new JToolBar();
      init();
      setSize( 300, 150 );
      getContentPane().setBackground( orig );
      setVisible( true );
   }
   public void actionPerformed( ActionEvent e ) {
      String s = e.getActionCommand();
      if ( s.equals( exitString ) )
        System.exit( 0 ); 
      else if ( s.equals( restoreString ) )
        getContentPane().setBackground( orig );
      else 
        setColor( s );
   }
   private void init() {
      initMenu( colorMenu, colorNames );
      menuBar.add( colorMenu );
      setJMenuBar( menuBar );
      addButton( exitString ); addButton( restoreString );
      getContentPane().add( controls, BorderLayout.SOUTH );
   }
   private void addButton( String n ) {
      JButton j = new JButton( n );
      controls.add( j );
      j.addActionListener( this );
   }
   private void initMenu( JMenu menu, String[ ] items ) {
      for ( int i = 0; i < items.length; i++ ) {
        JMenuItem item = new JMenuItem( items[ i ], 
                                        items[ i ].charAt( 0 ) );
        item.addActionListener( this );
        menu.add( item );
      }         
   }
   private void setColor( String c ) {
      int i = 0;
      while ( i < colorNames.length ) 
        if ( c.equals( colorNames[ i ] ) ) {
          getContentPane().setBackground( colors[ i ] );
          break;
        }
        else
          i++;
   }
   private JMenuBar menuBar;
   private JToolBar controls;
   private JMenu colorMenu;
   private JButton exit;
   private JButton restore;
   private static final String exitString = " Exit ";
   private static final String restoreString = " Restore ";
   private static final Color orig = Color.white;
   private static final String[ ] colorNames = 
      { "Blue", "Cyan", "Gray", "Orange", "Pink" };
   private static final Color[ ] colors =
      { Color.blue, Color.cyan, Color.gray, Color.orange, Color.pink };
}