Java tutorial
/* * * Copyright (c) 1998 Sun Microsystems, Inc. All Rights Reserved. * * Sun grants you ("Licensee") a non-exclusive, royalty free, license to use, * modify and redistribute this software in source and binary code form, * provided that i) this copyright notice and license appear on all copies of * the software; and ii) Licensee does not utilize the software in a manner * which is disparaging to Sun. * * This software is provided "AS IS," without a warranty of any kind. ALL * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING ANY * IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR * NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE * LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING * OR DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR ITS * LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, * INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER * CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF * OR INABILITY TO USE SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE * POSSIBILITY OF SUCH DAMAGES. * * This software is not designed or intended for use in on-line control of * aircraft, air traffic, aircraft navigation or aircraft communications; or in * the design, construction, operation or maintenance of any nuclear * facility. Licensee represents and warrants that it will not use or * redistribute the Software for such purposes. */ import java.awt.BorderLayout; import java.awt.Color; import java.awt.Component; import java.awt.Container; import java.awt.Dimension; import java.awt.Graphics; import java.awt.Image; import java.awt.Point; import java.awt.Toolkit; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.WindowAdapter; import java.awt.image.BufferedImage; import javax.swing.BorderFactory; import javax.swing.Box; import javax.swing.BoxLayout; import javax.swing.ButtonGroup; import javax.swing.ImageIcon; import javax.swing.JButton; import javax.swing.JComponent; import javax.swing.JDialog; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.JRadioButton; import javax.swing.UIManager; public class FrameDemo2 extends WindowAdapter implements ActionListener { private Point lastLocation = null; private int maxX = 500; private int maxY = 500; // the main frame's default button private static JButton defaultButton = null; // constants for action commands protected final static String NO_DECORATIONS = "no_dec"; protected final static String LF_DECORATIONS = "laf_dec"; protected final static String WS_DECORATIONS = "ws_dec"; protected final static String CREATE_WINDOW = "new_win"; protected final static String DEFAULT_ICON = "def_icon"; protected final static String FILE_ICON = "file_icon"; protected final static String PAINT_ICON = "paint_icon"; // true if the next frame created should have no window decorations protected boolean noDecorations = false; // true if the next frame created should have setIconImage called protected boolean specifyIcon = false; // true if the next frame created should have a custom painted icon protected boolean createIcon = false; // Perform some initialization. public FrameDemo2() { Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize(); maxX = screenSize.width - 50; maxY = screenSize.height - 50; } // Create a new MyFrame object and show it. public void showNewWindow() { JFrame frame = new MyFrame(); // Take care of the no window decorations case. // NOTE: Unless you really need the functionality // provided by JFrame, you would usually use a // Window or JWindow instead of an undecorated JFrame. if (noDecorations) { frame.setUndecorated(true); } // Set window location. if (lastLocation != null) { // Move the window over and down 40 pixels. lastLocation.translate(40, 40); if ((lastLocation.x > maxX) || (lastLocation.y > maxY)) { lastLocation.setLocation(0, 0); } frame.setLocation(lastLocation); } else { lastLocation = frame.getLocation(); } // Calling setIconImage sets the icon displayed when the window // is minimized. Most window systems (or look and feels, if // decorations are provided by the look and feel) also use this // icon in the window decorations. if (specifyIcon) { if (createIcon) { frame.setIconImage(createFDImage()); // create an icon from scratch } else { frame.setIconImage(getFDImage()); // get the icon from a file } } // Show window. frame.setSize(new Dimension(170, 100)); frame.setVisible(true); } // Create the window-creation controls that go in the main window. protected JComponent createOptionControls() { JLabel label1 = new JLabel("Decoration options for subsequently created frames:"); ButtonGroup bg1 = new ButtonGroup(); JLabel label2 = new JLabel("Icon options:"); ButtonGroup bg2 = new ButtonGroup(); // Create the buttons JRadioButton rb1 = new JRadioButton(); rb1.setText("Look and feel decorated"); rb1.setActionCommand(LF_DECORATIONS); rb1.addActionListener(this); rb1.setSelected(true); bg1.add(rb1); // JRadioButton rb2 = new JRadioButton(); rb2.setText("Window system decorated"); rb2.setActionCommand(WS_DECORATIONS); rb2.addActionListener(this); bg1.add(rb2); // JRadioButton rb3 = new JRadioButton(); rb3.setText("No decorations"); rb3.setActionCommand(NO_DECORATIONS); rb3.addActionListener(this); bg1.add(rb3); // // JRadioButton rb4 = new JRadioButton(); rb4.setText("Default icon"); rb4.setActionCommand(DEFAULT_ICON); rb4.addActionListener(this); rb4.setSelected(true); bg2.add(rb4); // JRadioButton rb5 = new JRadioButton(); rb5.setText("Icon from a JPEG file"); rb5.setActionCommand(FILE_ICON); rb5.addActionListener(this); bg2.add(rb5); // JRadioButton rb6 = new JRadioButton(); rb6.setText("Painted icon"); rb6.setActionCommand(PAINT_ICON); rb6.addActionListener(this); bg2.add(rb6); // Add everything to a container. Box box = Box.createVerticalBox(); box.add(label1); box.add(Box.createVerticalStrut(5)); // spacer box.add(rb1); box.add(rb2); box.add(rb3); // box.add(Box.createVerticalStrut(15)); // spacer box.add(label2); box.add(Box.createVerticalStrut(5)); // spacer box.add(rb4); box.add(rb5); box.add(rb6); // Add some breathing room. box.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10)); return box; } // Create the button that goes in the main window. protected JComponent createButtonPane() { JButton button = new JButton("New window"); button.setActionCommand(CREATE_WINDOW); button.addActionListener(this); defaultButton = button; // Used later to make this the frame's default // button. // Center the button in a panel with some space around it. JPanel pane = new JPanel(); // use default FlowLayout pane.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5)); pane.add(button); return pane; } // Handle action events from all the buttons. public void actionPerformed(ActionEvent e) { String command = e.getActionCommand(); // Handle the New window button. if (CREATE_WINDOW.equals(command)) { showNewWindow(); // Handle the first group of radio buttons. } else if (NO_DECORATIONS.equals(command)) { noDecorations = true; JFrame.setDefaultLookAndFeelDecorated(false); } else if (WS_DECORATIONS.equals(command)) { noDecorations = false; JFrame.setDefaultLookAndFeelDecorated(false); } else if (LF_DECORATIONS.equals(command)) { noDecorations = false; JFrame.setDefaultLookAndFeelDecorated(true); // Handle the second group of radio buttons. } else if (DEFAULT_ICON.equals(command)) { specifyIcon = false; } else if (FILE_ICON.equals(command)) { specifyIcon = true; createIcon = false; } else if (PAINT_ICON.equals(command)) { specifyIcon = true; createIcon = true; } } // Creates an icon-worthy Image from scratch. protected static Image createFDImage() { // Create a 16x16 pixel image. BufferedImage bi = new BufferedImage(16, 16, BufferedImage.TYPE_INT_RGB); // Draw into it. Graphics g = bi.getGraphics(); g.setColor(Color.BLACK); g.fillRect(0, 0, 15, 15); g.setColor(Color.RED); g.fillOval(5, 3, 6, 6); // Clean up. g.dispose(); // Return it. return bi; } // Returns an Image or null. protected static Image getFDImage() { java.net.URL imgURL = FrameDemo2.class.getResource("images/FD.jpg"); if (imgURL != null) { return new ImageIcon(imgURL).getImage(); } else { return null; } } /** * Create the GUI and show it. For thread safety, this method should be * invoked from the event-dispatching thread. */ private static void createAndShowGUI() { // Use the Java look and feel. try { UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName()); } catch (Exception e) { } // Make sure we have nice window decorations. JFrame.setDefaultLookAndFeelDecorated(true); JDialog.setDefaultLookAndFeelDecorated(true); // Instantiate the controlling class. JFrame frame = new JFrame("FrameDemo2"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // Create and set up the content pane. FrameDemo2 demo = new FrameDemo2(); // Add components to it. Container contentPane = frame.getContentPane(); contentPane.add(demo.createOptionControls(), BorderLayout.CENTER); contentPane.add(demo.createButtonPane(), BorderLayout.PAGE_END); frame.getRootPane().setDefaultButton(defaultButton); // Display the window. frame.pack(); frame.setLocationRelativeTo(null); // center it frame.setVisible(true); } // Start the demo. 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(); } }); } class MyFrame extends JFrame implements ActionListener { // Create a frame with a button. public MyFrame() { super("A window"); setDefaultCloseOperation(DISPOSE_ON_CLOSE); // This button lets you close even an undecorated window. JButton button = new JButton("Close window"); button.addActionListener(this); // Place the button near the bottom of the window. Container contentPane = getContentPane(); contentPane.setLayout(new BoxLayout(contentPane, BoxLayout.PAGE_AXIS)); contentPane.add(Box.createVerticalGlue()); // takes all extra space contentPane.add(button); button.setAlignmentX(Component.CENTER_ALIGNMENT); // horizontally centered contentPane.add(Box.createVerticalStrut(5)); // spacer } // Make the button do the same thing as the default close operation // (DISPOSE_ON_CLOSE). public void actionPerformed(ActionEvent e) { setVisible(false); dispose(); } } }