MainClass.java Source code

Introduction

Here is the source code for MainClass.java

Source

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.DefaultComboBoxModel;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;

public class MainClass {

    public static void main(String args[]) {
        final JFrame frame = new JFrame("Change Look");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        ActionListener actionListener = new ActionListener() {
            public void actionPerformed(ActionEvent actionEvent) {
                Object source = actionEvent.getSource();
                String lafClassName = null;
                if (source instanceof JComboBox) {
                    JComboBox comboBox = (JComboBox) source;
                    lafClassName = (String) comboBox.getSelectedItem();
                } else if (source instanceof JButton) {
                    lafClassName = actionEvent.getActionCommand();
                }
                if (lafClassName != null) {
                    final String finalLafClassName = lafClassName;
                    try {
                        UIManager.setLookAndFeel(finalLafClassName);
                        SwingUtilities.updateComponentTreeUI(frame);
                    } catch (Exception exception) {
                        JOptionPane.showMessageDialog(frame, "Can't change look and feel", "Invalid PLAF",
                                JOptionPane.ERROR_MESSAGE);
                    }
                }
            }
        };

        UIManager.LookAndFeelInfo looks[] = UIManager.getInstalledLookAndFeels();

        DefaultComboBoxModel model = new DefaultComboBoxModel();
        JComboBox comboBox = new JComboBox(model);

        JPanel panel = new JPanel();

        for (int i = 0, n = looks.length; i < n; i++) {
            JButton button = new JButton(looks[i].getName());
            model.addElement(looks[i].getClassName());
            button.setActionCommand(looks[i].getClassName());
            button.addActionListener(actionListener);
            panel.add(button);
        }

        comboBox.addActionListener(actionListener);

        frame.add(comboBox, BorderLayout.NORTH);
        frame.add(panel, BorderLayout.SOUTH);
        frame.setSize(350, 150);
        frame.setVisible(true);
    }
}