Java tutorial
/* * Copyright (c) 1995, 2008, Oracle and/or its affiliates. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * - Neither the name of Oracle or the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ package components; import javax.swing.*; import java.awt.*; import java.awt.event.*; /** * A 1.4 application that brings up a ListDialog. */ public class ListDialogRunner { static JFrame frame; static String[] names = { "Arlo", "Cosmo", "Elmo", "Hugo", "Jethro", "Laszlo", "Milo", "Nemo", "Otto", "Ringo", "Rocco", "Rollo" }; public static JPanel createUI() { //Create the labels. JLabel intro = new JLabel("The chosen name:"); final JLabel name = new JLabel(names[1]); intro.setLabelFor(name); //Use a wacky font if it exists. If not, this falls //back to a font we know exists. name.setFont(getAFont()); //Create the button. final JButton button = new JButton("Pick a new name..."); button.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { String selectedName = ListDialog.showDialog(frame, button, "Baby names ending in O:", "Name Chooser", names, name.getText(), "Cosmo "); name.setText(selectedName); } }); //Create the panel we'll return and set up the layout. JPanel panel = new JPanel(); panel.setLayout(new BoxLayout(panel, BoxLayout.PAGE_AXIS)); panel.setBorder(BorderFactory.createEmptyBorder(20, 20, 10, 20)); intro.setAlignmentX(JComponent.CENTER_ALIGNMENT); name.setAlignmentX(JComponent.CENTER_ALIGNMENT); button.setAlignmentX(JComponent.CENTER_ALIGNMENT); //Add the labels to the content pane. panel.add(intro); panel.add(Box.createVerticalStrut(5)); //extra space panel.add(name); //Add a vertical spacer that also guarantees us a minimum width: panel.add(Box.createRigidArea(new Dimension(150, 10))); //Add the button. panel.add(button); return panel; } /** * Finds a cursive font to use, or falls back to using * an italic serif font. */ protected static Font getAFont() { //initial strings of desired fonts String[] desiredFonts = { "French Script", "FrenchScript", "Script" }; String[] existingFamilyNames = null; //installed fonts String fontName = null; //font we'll use //Search for all installed font families. The first //call may take a while on some systems with hundreds of //installed fonts, so if possible execute it in idle time, //and certainly not in a place that delays painting of //the UI (for example, when bringing up a menu). // //In systems with malformed fonts, this code might cause //serious problems; use the latest JRE in this case. (You'll //see the same problems if you use Swing's HTML support or //anything else that searches for all fonts.) If this call //causes problems for you under the latest JRE, please let //us know. GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment(); if (ge != null) { existingFamilyNames = ge.getAvailableFontFamilyNames(); } //See if there's one we like. if ((existingFamilyNames != null) && (desiredFonts != null)) { int i = 0; while ((fontName == null) && (i < desiredFonts.length)) { //Look for a font whose name starts with desiredFonts[i]. int j = 0; while ((fontName == null) && (j < existingFamilyNames.length)) { if (existingFamilyNames[j].startsWith(desiredFonts[i])) { //We've found a match. Test whether it can display //the Latin character 'A'. (You might test for //a different character if you're using a different //language.) Font f = new Font(existingFamilyNames[j], Font.PLAIN, 1); if (f.canDisplay('A')) { fontName = existingFamilyNames[j]; System.out.println("Using font: " + fontName); } } j++; //Look at next existing font name. } i++; //Look for next desired font. } } //Return a valid Font. if (fontName != null) { return new Font(fontName, Font.PLAIN, 36); } else { return new Font("Serif", Font.ITALIC, 36); } } /** * 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. frame = new JFrame("Name That Baby"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //Create and set up the content pane. JComponent newContentPane = createUI(); newContentPane.setOpaque(true); //content panes must be opaque frame.setContentPane(newContentPane); //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(); } }); } }