toolbardemo2.java

java tutorial.sun公司官方出品。java入门书籍。最新版

/*
 * 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.
 */ 

package components;

/*
 * ToolBarDemo2.java requires the following addditional files:
 * images/Back24.gif
 * images/Forward24.gif
 * images/Up24.gif
 */

import javax.swing.JToolBar;
import javax.swing.JButton;
import javax.swing.ImageIcon;
import javax.swing.JTextField;

import javax.swing.JFrame;
import javax.swing.JTextArea;
import javax.swing.JScrollPane;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.SwingUtilities;

import java.net.URL;

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

public class ToolBarDemo2 extends JPanel
                          implements ActionListener {
    protected JTextArea textArea;
    protected String newline = "\n";
    static final private String PREVIOUS = "previous";
    static final private String UP = "up";
    static final private String NEXT = "next";
    static final private String SOMETHING_ELSE = "other";
    static final private String TEXT_ENTERED = "text";

    public ToolBarDemo2() {
        super(new BorderLayout());

        //Create the toolbar.
        JToolBar toolBar = new JToolBar("Still draggable");
        addButtons(toolBar);
        toolBar.setFloatable(false);
        toolBar.setRollover(true);

        //Create the text area used for output.  Request
        //enough space for 5 rows and 30 columns.
        textArea = new JTextArea(5, 30);
        textArea.setEditable(false);
        JScrollPane scrollPane = new JScrollPane(textArea);

        //Lay out the main panel.
        setPreferredSize(new Dimension(450, 130));
        add(toolBar, BorderLayout.PAGE_START);
        add(scrollPane, BorderLayout.CENTER);
    }

    protected void addButtons(JToolBar toolBar) {
        JButton button = null;

        //first button
        button = makeNavigationButton("Back24", PREVIOUS,
                                      "Back to previous something-or-other",
                                      "Previous");
        toolBar.add(button);

        //second button
        button = makeNavigationButton("Up24", UP,
                                      "Up to something-or-other",
                                      "Up");
        toolBar.add(button);

        //third button
        button = makeNavigationButton("Forward24", NEXT,
                                      "Forward to something-or-other",
                                      "Next");
        toolBar.add(button);

        //separator
        toolBar.addSeparator();

        //fourth button
        button = new JButton("Another button");
        button.setActionCommand(SOMETHING_ELSE);
        button.setToolTipText("Something else");
        button.addActionListener(this);
        toolBar.add(button);

        //fifth component is NOT a button!
        JTextField textField = new JTextField("A text field");
        textField.setColumns(10);
        textField.addActionListener(this);
        textField.setActionCommand(TEXT_ENTERED);
        toolBar.add(textField);
    }

    protected JButton makeNavigationButton(String imageName,
                                           String actionCommand,
                                           String toolTipText,
                                           String altText) {
        //Look for the image.
        String imgLocation = "images/"
                             + imageName
                             + ".gif";
        URL imageURL = ToolBarDemo2.class.getResource(imgLocation);

        //Create and initialize the button.
        JButton button = new JButton();
        button.setActionCommand(actionCommand);
        button.setToolTipText(toolTipText);
        button.addActionListener(this);

        if (imageURL != null) {                      //image found
            button.setIcon(new ImageIcon(imageURL, altText));
        } else {                                     //no image found
            button.setText(altText);
            System.err.println("Resource not found: "
                               + imgLocation);
        }

        return button;
    }

    public void actionPerformed(ActionEvent e) {
        String cmd = e.getActionCommand();
        String description = null;

        // Handle each button.
        if (PREVIOUS.equals(cmd)) { //first button clicked
            description = "taken you to the previous <something>.";
        } else if (UP.equals(cmd)) { // second button clicked
            description = "taken you up one level to <something>.";
        } else if (NEXT.equals(cmd)) { // third button clicked
            description = "taken you to the next <something>.";
        } else if (SOMETHING_ELSE.equals(cmd)) { // fourth button clicked
            description = "done something else.";
        } else if (TEXT_ENTERED.equals(cmd)) { // text field
            JTextField tf = (JTextField)e.getSource();
            String text = tf.getText();
            tf.setText("");
            description = "done something with this text: "
                          + newline + "  \""
                          + text + "\"";
        }

        displayResult("If this were a real app, it would have "
                        + description);
    }

    protected void displayResult(String actionDescription) {
        textArea.append(actionDescription + newline);
        textArea.setCaretPosition(textArea.getDocument().getLength());
    }

    /**
     * Create the GUI and show it.  For thread safety,
     * this method should be invoked from the
     * event dispatch thread.
     */
    private static void createAndShowGUI() {
        //Create and set up the window.
        JFrame frame = new JFrame("ToolBarDemo2");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Add content to the window.
        frame.add(new ToolBarDemo2());

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
	//Schedule a job for the event dispatch thread:
        //creating and showing this application's GUI.
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                //Turn off metal's use of bold fonts
	        UIManager.put("swing.boldMetal", Boolean.FALSE);
	       	createAndShowGUI();
            }
        });
    }
}