Java tutorial
/* * Copyright (c) 1995 - 2008 Sun Microsystems, Inc. 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 Sun Microsystems nor 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. */ import java.awt.BorderLayout; import java.awt.Dimension; import java.awt.Font; import java.awt.Frame; import java.awt.GridLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.ComponentAdapter; import java.awt.event.ComponentEvent; import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import java.beans.PropertyChangeEvent; import java.beans.PropertyChangeListener; 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.JDialog; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JRadioButton; import javax.swing.JTabbedPane; import javax.swing.JTextField; import javax.swing.border.Border; /* * DialogDemo.java requires these files: CustomDialog.java images/middle.gif */ public class DialogDemo extends JPanel { JLabel label; ImageIcon icon = createImageIcon("images/middle.gif"); JFrame frame; String simpleDialogDesc = "Some simple message dialogs"; String iconDesc = "A JOptionPane has its choice of icons"; String moreDialogDesc = "Some more dialogs"; CustomDialog customDialog; /** Creates the GUI shown inside the frame's content pane. */ public DialogDemo(JFrame frame) { super(new BorderLayout()); this.frame = frame; customDialog = new CustomDialog(frame, "geisel", this); customDialog.pack(); // Create the components. JPanel frequentPanel = createSimpleDialogBox(); JPanel featurePanel = createFeatureDialogBox(); JPanel iconPanel = createIconDialogBox(); label = new JLabel("Click the \"Show it!\" button" + " to bring up the selected dialog.", JLabel.CENTER); // Lay them out. Border padding = BorderFactory.createEmptyBorder(20, 20, 5, 20); frequentPanel.setBorder(padding); featurePanel.setBorder(padding); iconPanel.setBorder(padding); JTabbedPane tabbedPane = new JTabbedPane(); tabbedPane.addTab("Simple Modal Dialogs", null, frequentPanel, simpleDialogDesc); // tooltip text tabbedPane.addTab("More Dialogs", null, featurePanel, moreDialogDesc); // tooltip // text tabbedPane.addTab("Dialog Icons", null, iconPanel, iconDesc); // tooltip // text add(tabbedPane, BorderLayout.CENTER); add(label, BorderLayout.PAGE_END); label.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10)); } /** Sets the text displayed at the bottom of the frame. */ void setLabel(String newText) { label.setText(newText); } /** Returns an ImageIcon, or null if the path was invalid. */ protected static ImageIcon createImageIcon(String path) { java.net.URL imgURL = DialogDemo.class.getResource(path); if (imgURL != null) { return new ImageIcon(imgURL); } else { System.err.println("Couldn't find file: " + path); return null; } } /** Creates the panel shown by the first tab. */ private JPanel createSimpleDialogBox() { final int numButtons = 4; JRadioButton[] radioButtons = new JRadioButton[numButtons]; final ButtonGroup group = new ButtonGroup(); JButton showItButton = null; final String defaultMessageCommand = "default"; final String yesNoCommand = "yesno"; final String yeahNahCommand = "yeahnah"; final String yncCommand = "ync"; radioButtons[0] = new JRadioButton("OK (in the L&F's words)"); radioButtons[0].setActionCommand(defaultMessageCommand); radioButtons[1] = new JRadioButton("Yes/No (in the L&F's words)"); radioButtons[1].setActionCommand(yesNoCommand); radioButtons[2] = new JRadioButton("Yes/No " + "(in the programmer's words)"); radioButtons[2].setActionCommand(yeahNahCommand); radioButtons[3] = new JRadioButton("Yes/No/Cancel " + "(in the programmer's words)"); radioButtons[3].setActionCommand(yncCommand); for (int i = 0; i < numButtons; i++) { group.add(radioButtons[i]); } radioButtons[0].setSelected(true); showItButton = new JButton("Show it!"); showItButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { String command = group.getSelection().getActionCommand(); // ok dialog if (command == defaultMessageCommand) { JOptionPane.showMessageDialog(frame, "Eggs aren't supposed to be green."); // yes/no dialog } else if (command == yesNoCommand) { int n = JOptionPane.showConfirmDialog(frame, "Would you like green eggs and ham?", "An Inane Question", JOptionPane.YES_NO_OPTION); if (n == JOptionPane.YES_OPTION) { setLabel("Ewww!"); } else if (n == JOptionPane.NO_OPTION) { setLabel("Me neither!"); } else { setLabel("Come on -- tell me!"); } // yes/no (not in those words) } else if (command == yeahNahCommand) { Object[] options = { "Yes, please", "No way!" }; int n = JOptionPane.showOptionDialog(frame, "Would you like green eggs and ham?", "A Silly Question", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE, null, options, options[0]); if (n == JOptionPane.YES_OPTION) { setLabel("You're kidding!"); } else if (n == JOptionPane.NO_OPTION) { setLabel("I don't like them, either."); } else { setLabel("Come on -- 'fess up!"); } // yes/no/cancel (not in those words) } else if (command == yncCommand) { Object[] options = { "Yes, please", "No, thanks", "No eggs, no ham!" }; int n = JOptionPane.showOptionDialog(frame, "Would you like some green eggs to go " + "with that ham?", "A Silly Question", JOptionPane.YES_NO_CANCEL_OPTION, JOptionPane.QUESTION_MESSAGE, null, options, options[2]); if (n == JOptionPane.YES_OPTION) { setLabel("Here you go: green eggs and ham!"); } else if (n == JOptionPane.NO_OPTION) { setLabel("OK, just the ham, then."); } else if (n == JOptionPane.CANCEL_OPTION) { setLabel("Well, I'm certainly not going to eat them!"); } else { setLabel("Please tell me what you want!"); } } return; } }); return createPane(simpleDialogDesc + ":", radioButtons, showItButton); } /** * Used by createSimpleDialogBox and createFeatureDialogBox to create a pane * containing a description, a single column of radio buttons, and the Show * it! button. */ private JPanel createPane(String description, JRadioButton[] radioButtons, JButton showButton) { int numChoices = radioButtons.length; JPanel box = new JPanel(); JLabel label = new JLabel(description); box.setLayout(new BoxLayout(box, BoxLayout.PAGE_AXIS)); box.add(label); for (int i = 0; i < numChoices; i++) { box.add(radioButtons[i]); } JPanel pane = new JPanel(new BorderLayout()); pane.add(box, BorderLayout.PAGE_START); pane.add(showButton, BorderLayout.PAGE_END); return pane; } /** * Like createPane, but creates a pane with 2 columns of radio buttons. The * number of buttons passed in *must* be even. */ private JPanel create2ColPane(String description, JRadioButton[] radioButtons, JButton showButton) { JLabel label = new JLabel(description); int numPerColumn = radioButtons.length / 2; JPanel grid = new JPanel(new GridLayout(0, 2)); for (int i = 0; i < numPerColumn; i++) { grid.add(radioButtons[i]); grid.add(radioButtons[i + numPerColumn]); } JPanel box = new JPanel(); box.setLayout(new BoxLayout(box, BoxLayout.PAGE_AXIS)); box.add(label); grid.setAlignmentX(0.0f); box.add(grid); JPanel pane = new JPanel(new BorderLayout()); pane.add(box, BorderLayout.PAGE_START); pane.add(showButton, BorderLayout.PAGE_END); return pane; } /* * Creates the panel shown by the 3rd tab. These dialogs are implemented using * showMessageDialog, but you can specify the icon (using similar code) for * any other kind of dialog, as well. */ private JPanel createIconDialogBox() { JButton showItButton = null; final int numButtons = 6; JRadioButton[] radioButtons = new JRadioButton[numButtons]; final ButtonGroup group = new ButtonGroup(); final String plainCommand = "plain"; final String infoCommand = "info"; final String questionCommand = "question"; final String errorCommand = "error"; final String warningCommand = "warning"; final String customCommand = "custom"; radioButtons[0] = new JRadioButton("Plain (no icon)"); radioButtons[0].setActionCommand(plainCommand); radioButtons[1] = new JRadioButton("Information icon"); radioButtons[1].setActionCommand(infoCommand); radioButtons[2] = new JRadioButton("Question icon"); radioButtons[2].setActionCommand(questionCommand); radioButtons[3] = new JRadioButton("Error icon"); radioButtons[3].setActionCommand(errorCommand); radioButtons[4] = new JRadioButton("Warning icon"); radioButtons[4].setActionCommand(warningCommand); radioButtons[5] = new JRadioButton("Custom icon"); radioButtons[5].setActionCommand(customCommand); for (int i = 0; i < numButtons; i++) { group.add(radioButtons[i]); } radioButtons[0].setSelected(true); showItButton = new JButton("Show it!"); showItButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { String command = group.getSelection().getActionCommand(); // no icon if (command == plainCommand) { JOptionPane.showMessageDialog(frame, "Eggs aren't supposed to be green.", "A plain message", JOptionPane.PLAIN_MESSAGE); // information icon } else if (command == infoCommand) { JOptionPane.showMessageDialog(frame, "Eggs aren't supposed to be green.", "Inane informational dialog", JOptionPane.INFORMATION_MESSAGE); // XXX: It doesn't make sense to make a question with // XXX: only one button. // XXX: See "Yes/No (but not in those words)" for a better solution. // question icon } else if (command == questionCommand) { JOptionPane.showMessageDialog(frame, "You shouldn't use a message dialog " + "(like this)\n" + "for a question, OK?", "Inane question", JOptionPane.QUESTION_MESSAGE); // error icon } else if (command == errorCommand) { JOptionPane.showMessageDialog(frame, "Eggs aren't supposed to be green.", "Inane error", JOptionPane.ERROR_MESSAGE); // warning icon } else if (command == warningCommand) { JOptionPane.showMessageDialog(frame, "Eggs aren't supposed to be green.", "Inane warning", JOptionPane.WARNING_MESSAGE); // custom icon } else if (command == customCommand) { JOptionPane.showMessageDialog(frame, "Eggs aren't supposed to be green.", "Inane custom dialog", JOptionPane.INFORMATION_MESSAGE, icon); } } }); return create2ColPane(iconDesc + ":", radioButtons, showItButton); } /** Creates the panel shown by the second tab. */ private JPanel createFeatureDialogBox() { final int numButtons = 5; JRadioButton[] radioButtons = new JRadioButton[numButtons]; final ButtonGroup group = new ButtonGroup(); JButton showItButton = null; final String pickOneCommand = "pickone"; final String textEnteredCommand = "textfield"; final String nonAutoCommand = "nonautooption"; final String customOptionCommand = "customoption"; final String nonModalCommand = "nonmodal"; radioButtons[0] = new JRadioButton("Pick one of several choices"); radioButtons[0].setActionCommand(pickOneCommand); radioButtons[1] = new JRadioButton("Enter some text"); radioButtons[1].setActionCommand(textEnteredCommand); radioButtons[2] = new JRadioButton("Non-auto-closing dialog"); radioButtons[2].setActionCommand(nonAutoCommand); radioButtons[3] = new JRadioButton("Input-validating dialog " + "(with custom message area)"); radioButtons[3].setActionCommand(customOptionCommand); radioButtons[4] = new JRadioButton("Non-modal dialog"); radioButtons[4].setActionCommand(nonModalCommand); for (int i = 0; i < numButtons; i++) { group.add(radioButtons[i]); } radioButtons[0].setSelected(true); showItButton = new JButton("Show it!"); showItButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { String command = group.getSelection().getActionCommand(); // pick one of many if (command == pickOneCommand) { Object[] possibilities = { "ham", "spam", "yam" }; String s = (String) JOptionPane.showInputDialog(frame, "Complete the sentence:\n" + "\"Green eggs and...\"", "Customized Dialog", JOptionPane.PLAIN_MESSAGE, icon, possibilities, "ham"); // If a string was returned, say so. if ((s != null) && (s.length() > 0)) { setLabel("Green eggs and... " + s + "!"); return; } // If you're here, the return value was null/empty. setLabel("Come on, finish the sentence!"); // text input } else if (command == textEnteredCommand) { String s = (String) JOptionPane.showInputDialog(frame, "Complete the sentence:\n" + "\"Green eggs and...\"", "Customized Dialog", JOptionPane.PLAIN_MESSAGE, icon, null, "ham"); // If a string was returned, say so. if ((s != null) && (s.length() > 0)) { setLabel("Green eggs and... " + s + "!"); return; } // If you're here, the return value was null/empty. setLabel("Come on, finish the sentence!"); // non-auto-closing dialog } else if (command == nonAutoCommand) { final JOptionPane optionPane = new JOptionPane( "The only way to close this dialog is by\n" + "pressing one of the following buttons.\n" + "Do you understand?", JOptionPane.QUESTION_MESSAGE, JOptionPane.YES_NO_OPTION); // You can't use pane.createDialog() because that // method sets up the JDialog with a property change // listener that automatically closes the window // when a button is clicked. final JDialog dialog = new JDialog(frame, "Click a button", true); dialog.setContentPane(optionPane); dialog.setDefaultCloseOperation(JDialog.DO_NOTHING_ON_CLOSE); dialog.addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent we) { setLabel("Thwarted user attempt to close window."); } }); optionPane.addPropertyChangeListener(new PropertyChangeListener() { public void propertyChange(PropertyChangeEvent e) { String prop = e.getPropertyName(); if (dialog.isVisible() && (e.getSource() == optionPane) && (JOptionPane.VALUE_PROPERTY.equals(prop))) { // If you were going to check something // before closing the window, you'd do // it here. dialog.setVisible(false); } } }); dialog.pack(); dialog.setLocationRelativeTo(frame); dialog.setVisible(true); int value = ((Integer) optionPane.getValue()).intValue(); if (value == JOptionPane.YES_OPTION) { setLabel("Good."); } else if (value == JOptionPane.NO_OPTION) { setLabel("Try using the window decorations " + "to close the non-auto-closing dialog. " + "You can't!"); } else { setLabel("Window unavoidably closed (ESC?)."); } // non-auto-closing dialog with custom message area // NOTE: if you don't intend to check the input, // then just use showInputDialog instead. } else if (command == customOptionCommand) { customDialog.setLocationRelativeTo(frame); customDialog.setVisible(true); String s = customDialog.getValidatedText(); if (s != null) { // The text is valid. setLabel("Congratulations! " + "You entered \"" + s + "\"."); } // non-modal dialog } else if (command == nonModalCommand) { // Create the dialog. final JDialog dialog = new JDialog(frame, "A Non-Modal Dialog"); // Add contents to it. It must have a close button, // since some L&Fs (notably Java/Metal) don't provide one // in the window decorations for dialogs. JLabel label = new JLabel("<html><p align=center>" + "This is a non-modal dialog.<br>" + "You can have one or more of these up<br>" + "and still use the main window."); label.setHorizontalAlignment(JLabel.CENTER); Font font = label.getFont(); label.setFont(label.getFont().deriveFont(font.PLAIN, 14.0f)); JButton closeButton = new JButton("Close"); closeButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { dialog.setVisible(false); dialog.dispose(); } }); JPanel closePanel = new JPanel(); closePanel.setLayout(new BoxLayout(closePanel, BoxLayout.LINE_AXIS)); closePanel.add(Box.createHorizontalGlue()); closePanel.add(closeButton); closePanel.setBorder(BorderFactory.createEmptyBorder(0, 0, 5, 5)); JPanel contentPane = new JPanel(new BorderLayout()); contentPane.add(label, BorderLayout.CENTER); contentPane.add(closePanel, BorderLayout.PAGE_END); contentPane.setOpaque(true); dialog.setContentPane(contentPane); // Show it. dialog.setSize(new Dimension(300, 150)); dialog.setLocationRelativeTo(frame); dialog.setVisible(true); } } }); return createPane(moreDialogDesc + ":", radioButtons, showItButton); } /** * 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("DialogDemo"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // Create and set up the content pane. DialogDemo newContentPane = new DialogDemo(frame); 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(); } }); } } /* * Copyright (c) 1995 - 2008 Sun Microsystems, Inc. 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 Sun Microsystems nor 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. */ /* 1.4 example used by DialogDemo.java. */ class CustomDialog extends JDialog implements ActionListener, PropertyChangeListener { private String typedText = null; private JTextField textField; private DialogDemo dd; private String magicWord; private JOptionPane optionPane; private String btnString1 = "Enter"; private String btnString2 = "Cancel"; /** * Returns null if the typed string was invalid; otherwise, returns the string * as the user entered it. */ public String getValidatedText() { return typedText; } /** Creates the reusable dialog. */ public CustomDialog(Frame aFrame, String aWord, DialogDemo parent) { super(aFrame, true); dd = parent; magicWord = aWord.toUpperCase(); setTitle("Quiz"); textField = new JTextField(10); // Create an array of the text and components to be displayed. String msgString1 = "What was Dr. SEUSS's real last name?"; String msgString2 = "(The answer is \"" + magicWord + "\".)"; Object[] array = { msgString1, msgString2, textField }; // Create an array specifying the number of dialog buttons // and their text. Object[] options = { btnString1, btnString2 }; // Create the JOptionPane. optionPane = new JOptionPane(array, JOptionPane.QUESTION_MESSAGE, JOptionPane.YES_NO_OPTION, null, options, options[0]); // Make this dialog display it. setContentPane(optionPane); // Handle window closing correctly. setDefaultCloseOperation(DO_NOTHING_ON_CLOSE); addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent we) { /* * Instead of directly closing the window, we're going to change the * JOptionPane's value property. */ optionPane.setValue(new Integer(JOptionPane.CLOSED_OPTION)); } }); // Ensure the text field always gets the first focus. addComponentListener(new ComponentAdapter() { public void componentShown(ComponentEvent ce) { textField.requestFocusInWindow(); } }); // Register an event handler that puts the text into the option pane. textField.addActionListener(this); // Register an event handler that reacts to option pane state changes. optionPane.addPropertyChangeListener(this); } /** This method handles events for the text field. */ public void actionPerformed(ActionEvent e) { optionPane.setValue(btnString1); } /** This method reacts to state changes in the option pane. */ public void propertyChange(PropertyChangeEvent e) { String prop = e.getPropertyName(); if (isVisible() && (e.getSource() == optionPane) && (JOptionPane.VALUE_PROPERTY.equals(prop) || JOptionPane.INPUT_VALUE_PROPERTY.equals(prop))) { Object value = optionPane.getValue(); if (value == JOptionPane.UNINITIALIZED_VALUE) { // ignore reset return; } // Reset the JOptionPane's value. // If you don't do this, then if the user // presses the same button next time, no // property change event will be fired. optionPane.setValue(JOptionPane.UNINITIALIZED_VALUE); if (btnString1.equals(value)) { typedText = textField.getText(); String ucText = typedText.toUpperCase(); if (magicWord.equals(ucText)) { // we're done; clear and dismiss the dialog clearAndHide(); } else { // text was invalid textField.selectAll(); JOptionPane .showMessageDialog( CustomDialog.this, "Sorry, \"" + typedText + "\" " + "isn't a valid response.\n" + "Please enter " + magicWord + ".", "Try again", JOptionPane.ERROR_MESSAGE); typedText = null; textField.requestFocusInWindow(); } } else { // user closed dialog or clicked cancel dd.setLabel("It's OK. " + "We won't force you to type " + magicWord + "."); typedText = null; clearAndHide(); } } } /** This method clears the dialog and hides it. */ public void clearAndHide() { textField.setText(null); setVisible(false); } }