java 源码:实现电子书拖拽翻页

/** * Copyright 2007 Pieter-Jan Savat * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package be.savat.components; import java.awt.AlphaComposite; import java.awt.Color; import java.awt.Cursor; import java.awt.Font; import java.awt.GradientPaint; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.GraphicsConfiguration; import java.awt.Image; import java.awt.Point; import java.awt.Rectangle; import java.awt.RenderingHints; import java.awt.Shape; import java.awt.Transparency; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.KeyEvent; import java.awt.event.MouseEvent; import java.awt.geom.GeneralPath; import java.awt.image.BufferedImage; import java.awt.image.ImageObserver; import javax.swing.AbstractAction; import javax.swing.ImageIcon; import javax.swing.JPanel; import javax.swing.KeyStroke; import javax.swing.Timer; import javax.swing.event.MouseInputListener; /** * The BookPanel uses the page turn effect to navigate between pages. The images used * as pages are set by specifying their location, the basename and the extension. * Each image should have the same basename followed by its index, ranging 1 to x. * If a 0 index image exists at the location then it is used (even though it is not * counted in the nrOfPages for the setPages() method). * * Navigating through the book can be done by clicking in the bottomright or * bottomleft corner, by using the 4 arrow keys or by dragging and dropping * a page. * To turn pages programmatically either call nextPage() or previousPage(). Jumping * to a page can be done by calling setLeftPageIndex(). * * By default soft clipping is off and the borders at the edges of the papers are visible. * * TODO fade drop shadow on percentage turned (see passedThreshold for calculations) * * @author Pieter-Jan Savat */ public class JBookPanel extends JPanel implements MouseInputListener, ActionListener { protected static final double PI_DIV_2 = Math.PI / 2.0; protected enum AutomatedAction {AUTO_TURN, AUTO_DROP_GO_BACK, AUTO_DROP_BUT_TURN} protected int rotationX; protected double nextPageAngle; protected double backPageAngle; protected Timer timer; protected AutomatedAction action; protected Point autoPoint; protected Point tmpPoint; protected int leftPageIndex; protected Image currentLeftImage; protected Image currentRightImage; protected Image nextLeftImage; protected Image nextRightImage; protected Image previousLeftImage; protected Image previousRightImage; protected String pageLocation; protected String pageName; protected String pageExtension; protected int nrOfPages; protected boolean leftPageTurn; protected int refreshSpeed; // used to store the bounds of the book protected Rectangle bookBounds; protected int pageWidth; protected int shadowWidth; protected int cornerRegionSize; protected boolean softClipping; protected boolean borderLinesVisible; // vars for optimization and reuse protected Color shadowDarkColor; protected Color shadowNeutralColor; protected GeneralPath clipPath; /** * Constructor */ public JBookPanel() { super(); this.addMouseMotionListener(this); this.addMouseListener(this); this.getInputMap().put(KeyStroke.getKeyStroke(KeyEvent.VK_RIGHT, 0), "nextPage"); this.getInputMap().put(KeyStroke.getKeyStroke(KeyEvent.VK_UP, 0), "nextPage"); this.getActionMap().put("nextPage", new AbstractAction() { public void actionPerformed(final ActionEvent e) { leftPageTurn = false; nextPage(); }}); this.getInputMap().put(KeyStroke.getKeyStroke(KeyEvent.VK_LEFT, 0), "previousPage"); this.getInputMap().put(KeyStroke.getKeyStroke(KeyEvent.VK_DOWN, 0), "previousPage"); this.getActionMap().put("previousPage", new AbstractAction() { public void actionPerformed(final ActionEvent e) { previousPage(); }}); refreshSpeed = 25; shadowWidth = 100; cornerRegionSize = 20; bookBounds = new Rectangle(); softClipping = false; borderLinesVisible = true; clipPath = new GeneralPath(); shadowDarkColor = new Color(0,0,0,130); shadowNeutralColor = new Color(255,255,255,0); this.setBackground(Color.LIGHT_GRAY); timer = new Timer(refreshSpeed, this); timer.stop(); leftPageIndex = 1; setPages(null, null, null, 13, 210, 342); setMargins(70, 80); } /////////////////// // PAINT METHODS // /////////////////// @Override public void paintComponent(final Graphics g) { final Graphics2D g2 = (Graphics2D) g; setGraphicsHints(g2); // background g.setColor(this.getBackground()); g.fillRect(0, 0, this.getWidth(), this.getHeight()); // page 1 paintPage(g2, currentLeftImage, bookBounds.x, bookBounds.y, pageWidth, bookBounds.height, this, false); // page 2 paintPage(g2, currentRightImage, bookBounds.x + pageWidth, bookBounds.y, pageWidth, bookBounds.height, this, true); if (leftPageTurn) { if (softClipping) { paintLeftPageSoftClipped(g2); } else { paintLeftPage(g2); } } else { if (softClipping) { paintRightPageSoftClipped(g2); } else { paintRightPage(g2); } } } protected void paintLeftPage(final Graphics2D g2) { // translate to rotation point g2.translate(bookBounds.width + bookBounds.x - rotationX + bookBounds.x, bookBounds.y + bookBounds.height); // rotate over back of page A angle g2.rotate(-backPageAngle); // translate the amount already done final int done = bookBounds.width + bookBounds.x - rotationX; g2.translate(done - pageWidth, 0); // page 3 (= back of page 1) clipPath.reset(); clipPath.moveTo(pageWidth, 0); clipPath.lineTo(pageWidth-done, 0); clipPath.lineTo(pageWidth, -1 * (int)(Math.tan(PI_DIV_2 - nextPageAngle) * done)); clipPath.closePath(); final Shape s = g2.getClip(); g2.clip(clipPath); paintPage(g2, previousRightImage, 0, 0 - bookBounds.height, pageWidth, bookBounds.height, this, false); g2.setClip(s); // translate back g2.translate(pageWidth - done, 0); // rotate back g2.rotate(backPageAngle); // translate back g2.translate(rotationX - bookBounds.width - bookBounds.x - bookBounds.x, -bookBounds.y - bookBounds.height); // page 4 clipPath.reset(); clipPath.moveTo(bookBounds.x, bookBounds.height + bookBounds.y); clipPath.lineTo(bookBounds.x + done, bookBounds.height + bookBounds.y); clipPath.lineTo(bookBounds.x, bookBounds.height + bookBounds.y - (int)(Math.tan(PI_DIV_2 - nextPageAngle) * done)); clipPath.closePath(); g2.clip(clipPath); paintPage(g2, previousLeftImage, bookBounds.x, bookBounds.y, pageWidth, bookBounds.height, this, true); // add drop shadow final GradientPaint grad = new GradientPaint(bookBounds.x + done, bookBounds.height + bookBounds.y, shadowDarkColor, bookBounds.x + done - shadowWidth, bookBounds.height + bookBounds.y + (int)(Math.cos(PI_DIV_2 - nextPageAngle) * shadowWidth), shadowNeutralColor, false); g2.setPaint(grad); g2.fillRect(bookBounds.x, bookBounds.y, pageWidth, bookBounds.height); } protected void paintLeftPageSoftClipped(final Graphics2D g2) { // calculate amount done (traveled) final int done = bookBounds