/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/
/* $Id: PreviewPanel.java 952770 2010-06-08 19:01:56Z jeremias $ */
package org.apache.fop.render.awt.viewer;
import java.awt.Adjustable;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.Point;
import java.awt.Toolkit;
import java.awt.event.AdjustmentEvent;
import java.awt.event.AdjustmentListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.geom.Rectangle2D;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JViewport;
import javax.swing.SwingUtilities;
import javax.swing.border.EmptyBorder;
import org.apache.xmlgraphics.util.UnitConv;
import org.apache.fop.apps.FOPException;
import org.apache.fop.apps.FOUserAgent;
import org.apache.fop.apps.MimeConstants;
import org.apache.fop.area.PageViewport;
import org.apache.fop.render.awt.AWTRenderer;
/**
* <p>Holds a scrollpane with the rendered page(s) and handles actions performed
* to alter the display of the page.
* </p>
* <p>Use PreviewPanel when you want to embed a preview in your own application
* with your own controls. Use PreviewDialog when you want to use the standard
* Fop controls.
* </p>
* <p>In order to embed a PreviewPanel in your own app, create your own renderer,
* and your own agent. In order to support reloads, you may also implement your
* own Renderable extension or the default InputHandler. Setting the Renderable
* to null works fine though.
* Then call setPreviewDialogDisplayed(false) to hide the
* default dialog. Finally create a preview panel with the agent, renderable and
* renderer and add it to your gui:
* </p>
* <pre>
* FopFactory fopFactory = FopFactory.newInstance();
* AWTRenderer renderer = new AWTRenderer();
* FOUserAgent agent = fopFactory.newFOUserAgent();
* agent.setRendererOverride(renderer);
* renderer.setPreviewDialogDisplayed(false);
* renderer.setUserAgent(agent);
* renderer.setUserAgent(agent);
* previewPanel = new PreviewPanel(agent, null, renderer);
* previewPanel = new PreviewPanel(ua);
* myGui.add(previewPanel);
* </pre>
*
* In order to set options and display a page do:
* <pre>
* renderer.clearViewportList();
* // build report xml here
* reload(); // optional if setting changed
* </pre>
*
* If you wan't to change settings, don't call reload. A good example is
* to set the page to fill the screen and set the scrolling mode:
* <pre>
* double scale = previewPanel.getScaleToFitWindow();
* previewPanel.setScaleFactor(scale);
* previewPanel.setDisplayMode(PreviewPanel.CONTINUOUS);
* </pre>
*/
public class PreviewPanel extends JPanel {
/** Constant for setting single page display. */
public static final int SINGLE = 1;
/** Constant for setting continuous page display. */
public static final int CONTINUOUS = 2;
/** Constant for displaying even/odd pages side by side in continuous form. */
public static final int CONT_FACING = 3;
/** The number of pixels left empty at the top bottom and sides of the page. */
private static final int BORDER_SPACING = 10;
/** The main display area */
private JScrollPane previewArea;
/** The AWT renderer - often shared with PreviewDialog */
private AWTRenderer renderer;
/** The FOUserAgent associated with this panel - often shared with PreviewDialog */
protected FOUserAgent foUserAgent;
/**
* Renderable instance that can be used to reload and re-render a document after
* modifications.
*/
protected Renderable renderable;
/** The number of the page which is currently selected */
private int currentPage = 0;
/** The index of the first page displayed on screen. */
private int firstPage = 0;
/** The number of pages concurrently displayed on screen. */
private int pageRange = 1;
/** The display mode. One of SINGLE, CONTINUOUS or CONT_FACING. */
private int displayMode = SINGLE;
/** The component(s) that hold the rendered page(s) */
private ImageProxyPanel[] pagePanels = null;
/**
* Panel showing the page panels in a grid. Usually the dimensions
* of the grid are 1x1, nx1 or nx2.
*/
private JPanel gridPanel = null;
/** Asynchronous reloader thread, used when reload() method is called. */
private Reloader reloader;
/**
* Allows any mouse drag on the page area to scroll the display window.
*/
private ViewportScroller scroller;
/**
* Creates a new PreviewPanel instance.
* @param foUserAgent the user agent
* @param renderable the Renderable instance that is used to reload/re-render a document
* after modifications.
* @param renderer the AWT Renderer instance to paint with
*/
public PreviewPanel(FOUserAgent foUserAgent, Renderable renderable, AWTRenderer renderer) {
super(new GridLayout(1, 1));
this.renderable = renderable;
this.renderer = renderer;
this.foUserAgent = foUserAgent;
//Override target resolution for the computer screen
this.foUserAgent.setTargetResolution(Toolkit.getDefaultToolkit().getScreenResolution());
gridPanel = new JPanel();
gridPanel.setLayout(new GridLayout(0, 1)); // rows, cols
previewArea = new JScrollPane(gridPanel);
previewArea.getViewport().setBackground(Color.gray);
previewArea.getVerticalScrollBar().addAdjustmentListener(new PageNumberListener());
// FIXME should add scroll wheel support here at some point.
scroller = new ViewportScroller(previewArea.getViewport());
previewArea.addMouseListener(scroller);
previewArea.addMouseMotionListener(scroller);
previewArea.setMinimumSize(new Dimension(50, 50));
add(previewArea);
}
/**
* @return the currently visible page
*/
public int getPage() {
return currentPage;
}
/**
* Selects the given page, displays it on screen and notifies
* listeners about the change in selection.
* @param number the page number
*/
public void setPage(int number) {
int oldPage = currentPage;
if (displayMode == CONTINUOUS || displayMode == CONT_FACING) {
currentPage = number;
gridPanel.scrollRectToVisible(pagePanels[currentPage].getBounds());
} else { // single page mode
currentPage = number;
firstPage = currentPage;
}
showPage();
firePageChange(oldPage, currentPage);
}
/**
* Sets the display mode.
* @param mode One of SINGLE, CONTINUOUS or CONT_FACING.
*/
public void setDisplayMode(int mode) {
if (mode != displayMode) {
displayMode = mode;
gridPanel.setLayout(new GridLayout(0, displayMode == CONT_FACING ? 2 : 1));
reload();
}
}
/**
* Returns the display mode.
* @return mode One of SINGLE, CONTINUOUS or CONT_FACING.
*/
public int getDisplayMode() {
return displayMode;
}
/**
* Reloads and reformats document.
*/
public synchronized void reload() {
if (reloader == null || !reloader.isAlive()) {
reloader = new Reloader();
reloader.start();
}
}
/**
* Allows a (yet) simple visual debug of the document.
*/
void debug() {
renderer.debug = !renderer.debug;
reload();
}
/**
* Add a listener to receive notification of page change events. Events will
* be fired whenever the currentPage value is changed. The values recorded
* are 0-based.
* @param l the page change listener to add
*/
public void addPageChangeListener(PageChangeListener l) {
listenerList.add(PageChangeListener.class, l);
}
/**
* Removes a page change listener.
* @param l the page change listener to remove
*/
public void removePageChangeListener(PageChangeListener l) {
listenerList.remove(PageChangeListener.class, l);
}
/**
* Notify all registered listeners of a page change event.
* @param oldPage the old page
* @param newPage the new page
*/
protected void firePageChange(int oldPage, int newPage) {
Object[] listeners = listenerList.getListenerList();
PageChangeEvent e = null;
for (int i = listeners.length - 2; i >= 0; i -= 2) {
if (listeners[i] == PageChangeListener.class) {
if (e == null) {
e = new PageChangeEvent(this, newPage, oldPage);
}
((PageChangeListener)listeners[i + 1]).pageChanged(e);
}
}
}
/**
* Allows any mouse drag on the page area to scroll the display window.
*/
private class ViewportScroller implements MouseListener, MouseMotionListener {
/** The viewport to be scrolled */
private final JViewport viewport;
/** Starting position of a mouse drag - X co-ordinate */
private int startPosX = 0;
/** Starting position of a mouse drag - Y co-ordinate */
private int startPosY = 0;
ViewportScroller(JViewport vp) {
viewport = vp;
}
// ***** MouseMotionListener *****
public synchronized void mouseDragged(MouseEvent e) {
if (viewport == null) {
return;
}
int x = e.getX();
int y = e.getY();
int xmove = x - startPosX;
int ymove = y - startPosY;
int viewWidth = viewport.getExtentSize().width;
int viewHeight = viewport.getExtentSize().height;
int imageWidth = viewport.getViewSize().width;
int imageHeight = viewport.getViewSize().height;
Point viewPoint = viewport.getViewPosition();
int viewX = Math.max(0, Math.min(imageWidth - viewWidth, viewPoint.x - xmove));
int viewY = Math.max(0, Math.min(imageHeight - viewHeight, viewPoint.y - ymove));
viewport.setViewPosition(new Point(viewX, viewY));
startPosX = x;
startPosY = y;
}
public void mouseMoved(MouseEvent e) { }
// ***** MouseListener *****
public void mousePressed(MouseEvent e) {
startPosX = e.getX();
startPosY = e.getY();
}
public void mouseExited(MouseEvent e) { }
public void mouseEntered(MouseEvent e) { }
public void mouseClicked(MouseEvent e) { }
public void mouseReleased(MouseEvent e) { }
}
/**
* This class is used to reload document in a thread safe way.
*/
private class Reloader extends Thread {
public void run() {
if (!renderer.isRenderingDone()) {
// do not allow the reloading while FOP is still rendering
JOptionPane.showMessageDialog(previewArea,
"Cannot perform the requested operation until "
+ "all page are rendered. Please wait",
"Please wait ", 1 /* INFORMATION_MESSAGE */);
return;
}
pagePanels = null;
int savedCurrentPage = currentPage;
currentPage = 0;
gridPanel.removeAll();
switch(displayMode) {
case CONT_FACING:
// This page intentionally left blank
// Makes 0th/1st page on rhs
gridPanel.add(new JLabel(""));
case CONTINUOUS:
currentPage = 0;
firstPage = 0;
pageRange = renderer.getNumberOfPages();
break;
case SINGLE:
default:
currentPage = 0;
firstPage = 0;
pageRange = 1;
break;
}
pagePanels = new ImageProxyPanel[pageRange];
for (int pg = 0; pg < pageRange; pg++) {
pagePanels[pg] = new ImageProxyPanel(renderer, pg + firstPage);
pagePanels[pg].setBorder(new EmptyBorder(
BORDER_SPACING, BORDER_SPACING, BORDER_SPACING, BORDER_SPACING));
gridPanel.add(pagePanels[pg]);
}
try {
if (renderable != null) {
renderer.clearViewportList();
renderable.renderTo(foUserAgent, MimeConstants.MIME_FOP_AWT_PREVIEW);
}
} catch (FOPException e) {
e.printStackTrace();
// FIXME Should show exception in gui - was reportException(e);
}
setPage(savedCurrentPage);
}
}
private class PageNumberListener implements AdjustmentListener {
public void adjustmentValueChanged(AdjustmentEvent e) {
if (displayMode == PreviewPanel.CONTINUOUS || displayMode == PreviewPanel.CONT_FACING) {
Adjustable a = e.getAdjustable();
int value = +e.getValue();
int min = a.getMinimum();
int max = a.getMaximum();
int page = ( (renderer.getNumberOfPages() * value) / (max - min) );
if (page != currentPage) {
int oldPage = currentPage;
currentPage = page;
firePageChange(oldPage, currentPage);
}
}
}
}
/**
* Scales page image
* @param scale [0;1]
*/
public void setScaleFactor(double scale) {
renderer.setScaleFactor(scale);
reload();
}
/**
* Returns the scale factor required in order to fit either the current
* page within the current window or to fit two adjacent pages within
* the display if the displaymode is continuous.
* @return the requested scale factor
* @throws FOPException in case of an error while fetching the PageViewport
*/
public double getScaleToFitWindow() throws FOPException {
Dimension extents = previewArea.getViewport().getExtentSize();
return getScaleToFit(extents.getWidth() - 2 * BORDER_SPACING,
extents.getHeight() - 2 * BORDER_SPACING);
}
/**
* As getScaleToFitWindow, but ignoring the Y axis.
* @return the requested scale factor
* @throws FOPException in case of an error while fetching the PageViewport
*/
public double getScaleToFitWidth() throws FOPException {
Dimension extents = previewArea.getViewport().getExtentSize();
return getScaleToFit(extents.getWidth() - 2 * BORDER_SPACING, Double.MAX_VALUE);
}
/**
* Returns the scale factor required in order to fit either the current page or
* two adjacent pages within a window of the given height and width, depending
* on the display mode. In order to ignore either dimension,
* just specify it as Double.MAX_VALUE.
* @param viewWidth width of the view
* @param viewHeight height of the view
* @return the requested scale factor
* @throws FOPException in case of an error while fetching the PageViewport
*/
public double getScaleToFit(double viewWidth, double viewHeight) throws FOPException {
PageViewport pageViewport = renderer.getPageViewport(currentPage);
Rectangle2D pageSize = pageViewport.getViewArea();
float screenResolution = Toolkit.getDefaultToolkit().getScreenResolution();
float screenFactor = screenResolution / UnitConv.IN2PT;
double widthScale = viewWidth / (pageSize.getWidth() / 1000f) / screenFactor;
double heightScale = viewHeight / (pageSize.getHeight() / 1000f) / screenFactor;
return Math.min(displayMode == CONT_FACING ? widthScale / 2 : widthScale, heightScale);
}
/** Starts rendering process and shows the current page. */
public synchronized void showPage() {
ShowPageImage viewer = new ShowPageImage();
if (SwingUtilities.isEventDispatchThread()) {
viewer.run();
} else {
SwingUtilities.invokeLater(viewer);
}
}
/** This class is used to render the page image in a thread safe way. */
private class ShowPageImage implements Runnable {
/**
* The run method that does the actual rendering of the viewed page
*/
public void run() {
for (int pg = firstPage; pg < firstPage + pageRange; pg++) {
pagePanels[pg - firstPage].setPage(pg);
}
revalidate();
}
}
}