/* * BoxLayoutDemo.java requires no other files. */ import java.awt.Component; import java.awt.Container; import javax.swing.BoxLayout; import javax.swing.JButton; import javax.swing.JFrame; public class BoxLayoutDemo { public static void addComponentsToPane(Container pane) { pane.setLayout(new BoxLayout(pane, BoxLayout.Y_AXIS)); addAButton("Button 1", pane); addAButton("Button 2", pane); addAButton("Button 3", pane); addAButton("Long-Named Button 4", pane); addAButton("5", pane); } private static void addAButton(String text, Container container) { JButton button = new JButton(text); button.setAlignmentX(Component.CENTER_ALIGNMENT); container.add(button); } /** * Create the GUI and show it. For thread safety, * this method should be invoked from the * event-dispatching thread. */ private static void createAndShowGUI() { //Create and set up the window. JFrame frame = new JFrame("BoxLayoutDemo"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //Set up the content pane. addComponentsToPane(frame.getContentPane()); //Display the window. frame.pack(); frame.setVisible(true); } public static void main(String[] args) { //Schedule a job for the event-dispatching thread: //creating and showing this application's GUI. javax.swing.SwingUtilities.invokeLater(new Runnable() { public void run() { createAndShowGUI(); } }); } }