/* * 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 events; /* * MouseWheelEventDemo.java */ import java.awt.BorderLayout; import java.awt.Color; import java.awt.Dimension; import java.awt.event.MouseWheelEvent; import java.awt.event.MouseWheelListener; import javax.swing.*; public class MouseWheelEventDemo extends JPanel implements MouseWheelListener { JTextArea textArea; JScrollPane scrollPane; static final String NEWLINE = System.getProperty("line.separator"); public static void main(String[] args) { /* Use an appropriate Look and Feel */ try { //UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel"); //UIManager.setLookAndFeel("com.sun.java.swing.plaf.gtk.GTKLookAndFeel"); UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel"); } catch (UnsupportedLookAndFeelException ex) { ex.printStackTrace(); } catch (IllegalAccessException ex) { ex.printStackTrace(); } catch (InstantiationException ex) { ex.printStackTrace(); } catch (ClassNotFoundException ex) { ex.printStackTrace(); } /* Turn off metal's use of bold fonts */ UIManager.put("swing.boldMetal", Boolean.FALSE); //Schedule a job for the event dispatch thread: //creating and showing this application's GUI. javax.swing.SwingUtilities.invokeLater(new Runnable() { public void run() { createAndShowGUI(); } }); } /** * 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("MouseWheelEventDemo"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //Create and set up the content pane. JComponent newContentPane = new MouseWheelEventDemo(); newContentPane.setOpaque(true); //content panes must be opaque frame.setContentPane(newContentPane); //Display the window. frame.pack(); frame.setVisible(true); } public MouseWheelEventDemo() { super(new BorderLayout()); textArea = new JTextArea(); textArea.setEditable(false); scrollPane = new JScrollPane(textArea); scrollPane.setVerticalScrollBarPolicy( JScrollPane.VERTICAL_SCROLLBAR_ALWAYS); scrollPane.setPreferredSize(new Dimension(400, 250)); add(scrollPane, BorderLayout.CENTER); textArea.append("This text area displays information " + "about its mouse wheel events." + NEWLINE); //Register for mouse-wheel events on the text area. textArea.addMouseWheelListener(this); setPreferredSize(new Dimension(450, 350)); setBorder(BorderFactory.createEmptyBorder(20,20,20,20)); } //Append to the text area and make sure the new text is visible. void eventOutput(String eventDescription, MouseWheelEvent e) { textArea.append(e.getComponent().getClass().getName() + ": " + eventDescription); textArea.setCaretPosition(textArea.getDocument().getLength()); } public void mouseWheelMoved(MouseWheelEvent e) { String message; int notches = e.getWheelRotation(); if (notches < 0) { message = "Mouse wheel moved UP " + -notches + " notch(es)" + NEWLINE; } else { message = "Mouse wheel moved DOWN " + notches + " notch(es)" + NEWLINE; } if (e.getScrollType() == MouseWheelEvent.WHEEL_UNIT_SCROLL) { message += " Scroll type: WHEEL_UNIT_SCROLL" + NEWLINE; message += " Scroll amount: " + e.getScrollAmount() + " unit increments per notch" + NEWLINE; message += " Units to scroll: " + e.getUnitsToScroll() + " unit increments" + NEWLINE; message += " Vertical unit increment: " + scrollPane.getVerticalScrollBar().getUnitIncrement(1) + " pixels" + NEWLINE; } else { //scroll type == MouseWheelEvent.WHEEL_BLOCK_SCROLL message += " Scroll type: WHEEL_BLOCK_SCROLL" + NEWLINE; message += " Vertical block increment: " + scrollPane.getVerticalScrollBar().getBlockIncrement(1) + " pixels" + NEWLINE; } eventOutput(message, e); } }