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 javax.swing.border.*; import javax.accessibility.*; import java.awt.*; import java.awt.event.*; /* * LayeredPaneDemo.java requires * images/dukeWaveRed.gif. */ public class LayeredPaneDemo extends JPanel implements ActionListener, MouseMotionListener { private String[] layerStrings = { "Yellow (0)", "Magenta (1)", "Cyan (2)", "Red (3)", "Green (4)" }; private Color[] layerColors = { Color.yellow, Color.magenta, Color.cyan, Color.red, Color.green }; private JLayeredPane layeredPane; private JLabel dukeLabel; private JCheckBox onTop; private JComboBox layerList; //Action commands private static String ON_TOP_COMMAND = "ontop"; private static String LAYER_COMMAND = "layer"; //Adjustments to put Duke's toe at the cursor's tip. private static final int XFUDGE = 40; private static final int YFUDGE = 57; public LayeredPaneDemo() { setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS)); //Create and load the duke icon. final ImageIcon icon = createImageIcon("images/dukeWaveRed.gif"); //Create and set up the layered pane. layeredPane = new JLayeredPane(); layeredPane.setPreferredSize(new Dimension(300, 310)); layeredPane.setBorder(BorderFactory.createTitledBorder("Move the Mouse to Move Duke")); layeredPane.addMouseMotionListener(this); //This is the origin of the first label added. Point origin = new Point(10, 20); //This is the offset for computing the origin for the next label. int offset = 35; //Add several overlapping, colored labels to the layered pane //using absolute positioning/sizing. for (int i = 0; i < layerStrings.length; i++) { JLabel label = createColoredLabel(layerStrings[i], layerColors[i], origin); layeredPane.add(label, new Integer(i)); origin.x += offset; origin.y += offset; } //Create and add the Duke label to the layered pane. dukeLabel = new JLabel(icon); if (icon != null) { dukeLabel.setBounds(15, 225, icon.getIconWidth(), icon.getIconHeight()); } else { System.err.println("Duke icon not found; using black square instead."); dukeLabel.setBounds(15, 225, 30, 30); dukeLabel.setOpaque(true); dukeLabel.setBackground(Color.BLACK); } layeredPane.add(dukeLabel, new Integer(2), 0); //Add control pane and layered pane to this JPanel. add(Box.createRigidArea(new Dimension(0, 10))); add(createControlPanel()); add(Box.createRigidArea(new Dimension(0, 10))); add(layeredPane); } /** Returns an ImageIcon, or null if the path was invalid. */ protected static ImageIcon createImageIcon(String path) { java.net.URL imgURL = LayeredPaneDemo.class.getResource(path); if (imgURL != null) { return new ImageIcon(imgURL); } else { System.err.println("Couldn't find file: " + path); return null; } } //Create and set up a colored label. private JLabel createColoredLabel(String text, Color color, Point origin) { JLabel label = new JLabel(text); label.setVerticalAlignment(JLabel.TOP); label.setHorizontalAlignment(JLabel.CENTER); label.setOpaque(true); label.setBackground(color); label.setForeground(Color.black); label.setBorder(BorderFactory.createLineBorder(Color.black)); label.setBounds(origin.x, origin.y, 140, 140); return label; } //Create the control pane for the top of the frame. private JPanel createControlPanel() { onTop = new JCheckBox("Top Position in Layer"); onTop.setSelected(true); onTop.setActionCommand(ON_TOP_COMMAND); onTop.addActionListener(this); layerList = new JComboBox(layerStrings); layerList.setSelectedIndex(2); //cyan layer layerList.setActionCommand(LAYER_COMMAND); layerList.addActionListener(this); JPanel controls = new JPanel(); controls.add(layerList); controls.add(onTop); controls.setBorder(BorderFactory.createTitledBorder("Choose Duke's Layer and Position")); return controls; } //Make Duke follow the cursor. public void mouseMoved(MouseEvent e) { dukeLabel.setLocation(e.getX() - XFUDGE, e.getY() - YFUDGE); } public void mouseDragged(MouseEvent e) { } //do nothing //Handle user interaction with the check box and combo box. public void actionPerformed(ActionEvent e) { String cmd = e.getActionCommand(); if (ON_TOP_COMMAND.equals(cmd)) { if (onTop.isSelected()) layeredPane.moveToFront(dukeLabel); else layeredPane.moveToBack(dukeLabel); } else if (LAYER_COMMAND.equals(cmd)) { int position = onTop.isSelected() ? 0 : 1; layeredPane.setLayer(dukeLabel, layerList.getSelectedIndex(), position); } } /** * 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("LayeredPaneDemo"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //Create and set up the content pane. JComponent newContentPane = new LayeredPaneDemo(); 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(); } }); } }