Look and Feel

This chapter discusses:

• LookAndFeel and UIManager.
• Sample program to switch LookAndFeel.

LookAndFeel and UIManager

javax.swing.LookAndFeel - A Swing class representing a set of rules that define how each type of graphical components should look and feel.

javax.swing.UIManager - A Swing class managing the current LookAndFeel.

LookAndFeelTest.java

To find out which LookAndFeel is available on your local system, and to switch from one LookAndFeel to another, I wrote the following sample program:

/**
 * LookAndFeelTest.java
 * Copyright (c) 2002 by Dr. Herong Yang
 */
import java.awt.*;
import javax.swing.*;
public class LookAndFeelTest {
   public static void main(String[] a) {
      try {
         showFrame("Default LookAndFeel");
         String cn = UIManager.getSystemLookAndFeelClassName();
         UIManager.setLookAndFeel(cn);
         showFrame("System LookAndFeel");
         cn = UIManager.getCrossPlatformLookAndFeelClassName();
         UIManager.setLookAndFeel(cn);
         showFrame("Cross Platform LookAndFeel");
         cn = "com.sun.java.swing.plaf.motif.MotifLookAndFeel";
         UIManager.setLookAndFeel(cn);
         showFrame("Motif LookAndFeel");
      } catch (Exception e) {
         System.out.println("Exception: "+e);
      }
   }
   private static void showFrame(String t) {
      LookAndFeel laf = UIManager.getLookAndFeel();
      JFrame myFrame = new JFrame(t+": "+laf.getName());
      myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      Container myPane = myFrame.getContentPane();
      myPane.setLayout(new GridBagLayout());
      GridBagConstraints c = new GridBagConstraints();
      setMyConstraints(c,0,0,GridBagConstraints.CENTER);
      myPane.add(getFieldPanel(),c);
      setMyConstraints(c,0,1,GridBagConstraints.CENTER);
      myPane.add(getButtonPanel(),c);
      myFrame.pack();
      myFrame.setVisible(true);
   }
   private static JPanel getFieldPanel() {
      JPanel p = new JPanel(new GridBagLayout());
      p.setBorder(BorderFactory.createTitledBorder("Details"));
      GridBagConstraints c = new GridBagConstraints();
      setMyConstraints(c,0,0,GridBagConstraints.EAST);
      p.add(new JLabel("Name:"),c);
      setMyConstraints(c,1,0,GridBagConstraints.WEST);
      p.add(new JTextField(16),c);
      setMyConstraints(c,0,1,GridBagConstraints.EAST);
      p.add(new JLabel("System:"),c);
      setMyConstraints(c,1,1,GridBagConstraints.WEST);
      p.add(getSystemPanel(),c);
      setMyConstraints(c,0,2,GridBagConstraints.EAST);
      p.add(new JLabel("Language:"),c);
      setMyConstraints(c,1,2,GridBagConstraints.WEST);
      p.add(getLanguagePanel(),c);
      setMyConstraints(c,0,3,GridBagConstraints.EAST);
      p.add(new JLabel("Year:"),c);
      setMyConstraints(c,1,3,GridBagConstraints.WEST);
      p.add(new JComboBox(new String[] {"2001","2002","2003"}),c);
      return p;
   }
   private static JPanel getButtonPanel() {
      JPanel p = new JPanel(new GridBagLayout());
      p.add(new JButton("OK"));
      p.add(new JButton("Cancel"));
      return p;
   }
   private static JPanel getSystemPanel() {
      JRadioButton unixButton = new JRadioButton("Unix",true);
      JRadioButton winButton = new JRadioButton("Window",false);
      ButtonGroup systemGroup = new ButtonGroup();
      systemGroup.add(unixButton);
      systemGroup.add(winButton);
      JPanel p = new JPanel(new GridBagLayout());
      p.add(unixButton);
      p.add(winButton);
      return p;
   }
   private static JPanel getLanguagePanel() {
      JPanel p = new JPanel(new GridBagLayout());
      p.add(new JCheckBox("Java",true));
      p.add(new JCheckBox("C++",true));
      p.add(new JCheckBox("Perl",false));
      return p;
   }
   private static void setMyConstraints(GridBagConstraints c, 
      int gridx, int gridy, int anchor) {
      c.gridx = gridx;
      c.gridy = gridy;
      c.anchor = anchor;
   }
}

Run it. You should get 4 windows, representing the JDK default LookAndFeel, the local system default LookAndFeel, cross platform LookAndFeel, and the Motif LookAndFeel.

As you can see, the JDK default LookAndFeel is called Metal, which is also the cross platform LookAndFeel.