/*******************************************************************************
* Copyright (c) 2000, 2010 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.jface.internal.text.html;
import java.io.IOException;
import java.io.StringReader;
import java.util.Iterator;
import org.eclipse.swt.SWT;
import org.eclipse.swt.SWTError;
import org.eclipse.swt.browser.Browser;
import org.eclipse.swt.browser.LocationListener;
import org.eclipse.swt.browser.OpenWindowListener;
import org.eclipse.swt.browser.ProgressAdapter;
import org.eclipse.swt.browser.ProgressEvent;
import org.eclipse.swt.browser.WindowEvent;
import org.eclipse.swt.custom.StyleRange;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.graphics.TextLayout;
import org.eclipse.swt.graphics.TextStyle;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Slider;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.ListenerList;
import org.eclipse.jface.action.ToolBarManager;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.jface.text.AbstractInformationControl;
import org.eclipse.jface.text.IDelayedInputChangeProvider;
import org.eclipse.jface.text.IInformationControlExtension2;
import org.eclipse.jface.text.IInputChangedListener;
import org.eclipse.jface.text.TextPresentation;
/**
* Displays HTML information in a {@link org.eclipse.swt.browser.Browser} widget.
* <p>
* This {@link IInformationControlExtension2} expects {@link #setInput(Object)} to be called with an
* argument of type {@link BrowserInformationControlInput}.
* </p>
* <p>
* Moved into this package from <code>org.eclipse.jface.internal.text.revisions</code>.
* </p>
* <p>
* This class may be instantiated; it is not intended to be subclassed.
* </p>
* <p>
* Current problems:
* <ul>
* <li>the size computation is too small</li>
* <li>focusLost event is not sent - see https://bugs.eclipse.org/bugs/show_bug.cgi?id=84532</li>
* </ul>
* </p>
*
* @since 3.2
*/
public class BrowserInformationControl extends AbstractInformationControl implements IInformationControlExtension2, IDelayedInputChangeProvider {
/**
* Tells whether the SWT Browser widget and hence this information
* control is available.
*
* @param parent the parent component used for checking or <code>null</code> if none
* @return <code>true</code> if this control is available
*/
public static boolean isAvailable(Composite parent) {
if (!fgAvailabilityChecked) {
try {
Browser browser= new Browser(parent, SWT.NONE);
browser.dispose();
fgIsAvailable= true;
Slider sliderV= new Slider(parent, SWT.VERTICAL);
Slider sliderH= new Slider(parent, SWT.HORIZONTAL);
int width= sliderV.computeSize(SWT.DEFAULT, SWT.DEFAULT).x;
int height= sliderH.computeSize(SWT.DEFAULT, SWT.DEFAULT).y;
fgScrollBarSize= new Point(width, height);
sliderV.dispose();
sliderH.dispose();
} catch (SWTError er) {
fgIsAvailable= false;
} finally {
fgAvailabilityChecked= true;
}
}
return fgIsAvailable;
}
/**
* Minimal size constraints.
* @since 3.2
*/
private static final int MIN_WIDTH= 80;
private static final int MIN_HEIGHT= 50;
/**
* Availability checking cache.
*/
private static boolean fgIsAvailable= false;
private static boolean fgAvailabilityChecked= false;
/**
* Cached scroll bar width and height
* @since 3.4
*/
private static Point fgScrollBarSize;
/** The control's browser widget */
private Browser fBrowser;
/** Tells whether the browser has content */
private boolean fBrowserHasContent;
/** Text layout used to approximate size of content when rendered in browser */
private TextLayout fTextLayout;
/** Bold text style */
private TextStyle fBoldStyle;
private BrowserInformationControlInput fInput;
/**
* <code>true</code> iff the browser has completed loading of the last
* input set via {@link #setInformation(String)}.
* @since 3.4
*/
private boolean fCompleted= false;
/**
* The listener to be notified when a delayed location changing event happened.
* @since 3.4
*/
private IInputChangedListener fDelayedInputChangeListener;
/**
* The listeners to be notified when the input changed.
* @since 3.4
*/
private ListenerList/*<IInputChangedListener>*/fInputChangeListeners= new ListenerList(ListenerList.IDENTITY);
/**
* The symbolic name of the font used for size computations, or <code>null</code> to use dialog font.
* @since 3.4
*/
private final String fSymbolicFontName;
/**
* Creates a browser information control with the given shell as parent.
*
* @param parent the parent shell
* @param symbolicFontName the symbolic name of the font used for size computations
* @param resizable <code>true</code> if the control should be resizable
* @since 3.4
*/
public BrowserInformationControl(Shell parent, String symbolicFontName, boolean resizable) {
super(parent, resizable);
fSymbolicFontName= symbolicFontName;
create();
}
/**
* Creates a browser information control with the given shell as parent.
*
* @param parent the parent shell
* @param symbolicFontName the symbolic name of the font used for size computations
* @param statusFieldText the text to be used in the optional status field
* or <code>null</code> if the status field should be hidden
* @since 3.4
*/
public BrowserInformationControl(Shell parent, String symbolicFontName, String statusFieldText) {
super(parent, statusFieldText);
fSymbolicFontName= symbolicFontName;
create();
}
/**
* Creates a browser information control with the given shell as parent.
*
* @param parent the parent shell
* @param symbolicFontName the symbolic name of the font used for size computations
* @param toolBarManager the manager or <code>null</code> if toolbar is not desired
* @since 3.4
*/
public BrowserInformationControl(Shell parent, String symbolicFontName, ToolBarManager toolBarManager) {
super(parent, toolBarManager);
fSymbolicFontName= symbolicFontName;
create();
}
/*
* @see org.eclipse.jface.text.AbstractInformationControl#createContent(org.eclipse.swt.widgets.Composite)
*/
protected void createContent(Composite parent) {
fBrowser= new Browser(parent, SWT.NONE);
fBrowser.setJavascriptEnabled(false);
Display display= getShell().getDisplay();
fBrowser.setForeground(display.getSystemColor(SWT.COLOR_INFO_FOREGROUND));
fBrowser.setBackground(display.getSystemColor(SWT.COLOR_INFO_BACKGROUND));
fBrowser.addProgressListener(new ProgressAdapter() {
public void completed(ProgressEvent event) {
fCompleted= true;
}
});
fBrowser.addOpenWindowListener(new OpenWindowListener() {
public void open(WindowEvent event) {
event.required= true; // Cancel opening of new windows
}
});
// Replace browser's built-in context menu with none
fBrowser.setMenu(new Menu(getShell(), SWT.NONE));
createTextLayout();
}
/**
* {@inheritDoc}
* @deprecated use {@link #setInput(Object)}
*/
public void setInformation(final String content) {
setInput(new BrowserInformationControlInput(null) {
public String getHtml() {
return content;
}
public String getInputName() {
return ""; //$NON-NLS-1$
}
public Object getInputElement() {
return content;
}
});
}
/**
* {@inheritDoc} This control can handle {@link String} and
* {@link BrowserInformationControlInput}.
*/
public void setInput(Object input) {
Assert.isLegal(input == null || input instanceof String || input instanceof BrowserInformationControlInput);
if (input instanceof String) {
setInformation((String)input);
return;
}
fInput= (BrowserInformationControlInput)input;
String content= null;
if (fInput != null)
content= fInput.getHtml();
fBrowserHasContent= content != null && content.length() > 0;
if (!fBrowserHasContent)
content= "<html><body ></html>"; //$NON-NLS-1$
boolean RTL= (getShell().getStyle() & SWT.RIGHT_TO_LEFT) != 0;
boolean resizable= isResizable();
// The default "overflow:auto" would not result in a predictable width for the client area
// and the re-wrapping would cause visual noise
String[] styles= null;
if (RTL && resizable)
styles= new String[] { "direction:rtl;", "overflow:scroll;", "word-wrap:break-word;" }; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
else if (RTL && !resizable)
styles= new String[] { "direction:rtl;", "overflow:hidden;", "word-wrap:break-word;" }; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
else if (!resizable)
//XXX: In IE, "word-wrap: break-word;" causes bogus wrapping even in non-broken words :-(see e.g. Javadoc of String).
// Re-check whether we really still need this now that the Javadoc Hover header already sets this style.
styles= new String[] { "overflow:hidden;"/*, "word-wrap: break-word;"*/}; //$NON-NLS-1$
else
styles= new String[] { "overflow:scroll;" }; //$NON-NLS-1$
StringBuffer buffer= new StringBuffer(content);
HTMLPrinter.insertStyles(buffer, styles);
content= buffer.toString();
/*
* XXX: Should add some JavaScript here that shows something like
* "(continued...)" or "..." at the end of the visible area when the page overflowed
* with "overflow:hidden;".
*/
fCompleted= false;
fBrowser.setText(content);
Object[] listeners= fInputChangeListeners.getListeners();
for (int i= 0; i < listeners.length; i++)
((IInputChangedListener)listeners[i]).inputChanged(fInput);
}
/*
* @see IInformationControl#setVisible(boolean)
*/
public void setVisible(boolean visible) {
Shell shell= getShell();
if (shell.isVisible() == visible)
return;
if (!visible) {
super.setVisible(false);
setInput(null);
return;
}
/*
* The Browser widget flickers when made visible while it is not completely loaded.
* The fix is to delay the call to setVisible until either loading is completed
* (see ProgressListener in constructor), or a timeout has been reached.
*/
final Display display= shell.getDisplay();
// Make sure the display wakes from sleep after timeout:
display.timerExec(100, new Runnable() {
public void run() {
fCompleted= true;
}
});
while (!fCompleted) {
// Drive the event loop to process the events required to load the browser widget's contents:
if (!display.readAndDispatch()) {
display.sleep();
}
}
shell= getShell();
if (shell == null || shell.isDisposed())
return;
/*
* Avoids flickering when replacing hovers, especially on Vista in ON_CLICK mode.
* Causes flickering on GTK. Carbon does not care.
*/
if ("win32".equals(SWT.getPlatform())) //$NON-NLS-1$
shell.moveAbove(null);
super.setVisible(true);
}
/*
* @see org.eclipse.jface.text.AbstractInformationControl#setSize(int, int)
*/
public void setSize(int width, int height) {
fBrowser.setRedraw(false); // avoid flickering
try {
super.setSize(width, height);
} finally {
fBrowser.setRedraw(true);
}
}
/**
* Creates and initializes the text layout used
* to compute the size hint.
*
* @since 3.2
*/
private void createTextLayout() {
fTextLayout= new TextLayout(fBrowser.getDisplay());
// Initialize fonts
String symbolicFontName= fSymbolicFontName == null ? JFaceResources.DIALOG_FONT : fSymbolicFontName;
Font font= JFaceResources.getFont(symbolicFontName);
fTextLayout.setFont(font);
fTextLayout.setWidth(-1);
font= JFaceResources.getFontRegistry().getBold(symbolicFontName);
fBoldStyle= new TextStyle(font, null, null);
// Compute and set tab width
fTextLayout.setText(" "); //$NON-NLS-1$
int tabWidth= fTextLayout.getBounds().width;
fTextLayout.setTabs(new int[] { tabWidth });
fTextLayout.setText(""); //$NON-NLS-1$
}
/*
* @see org.eclipse.jface.text.AbstractInformationControl#handleDispose()
* @since 3.6
*/
protected void handleDispose() {
if (fTextLayout != null) {
fTextLayout.dispose();
fTextLayout= null;
}
fBrowser= null;
super.handleDispose();
}
/*
* @see IInformationControl#computeSizeHint()
*/
public Point computeSizeHint() {
Point sizeConstraints= getSizeConstraints();
Rectangle trim= computeTrim();
int height= trim.height;
//FIXME: The HTML2TextReader does not render <p> like a browser.
// Instead of inserting an empty line, it just adds a single line break.
// Furthermore, the indentation of <dl><dd> elements is too small (e.g with a long @see line)
TextPresentation presentation= new TextPresentation();
HTML2TextReader reader= new HTML2TextReader(new StringReader(fInput.getHtml()), presentation);
String text;
try {
text= reader.getString();
} catch (IOException e) {
text= ""; //$NON-NLS-1$
}
fTextLayout.setText(text);
fTextLayout.setWidth(sizeConstraints == null ? SWT.DEFAULT : sizeConstraints.x - trim.width);
Iterator iter= presentation.getAllStyleRangeIterator();
while (iter.hasNext()) {
StyleRange sr= (StyleRange)iter.next();
if (sr.fontStyle == SWT.BOLD)
fTextLayout.setStyle(fBoldStyle, sr.start, sr.start + sr.length - 1);
}
Rectangle bounds= fTextLayout.getBounds(); // does not return minimum width, see https://bugs.eclipse.org/bugs/show_bug.cgi?id=217446
int lineCount= fTextLayout.getLineCount();
int textWidth= 0;
for (int i= 0; i < lineCount; i++) {
Rectangle rect= fTextLayout.getLineBounds(i);
int lineWidth= rect.x + rect.width;
if (i == 0)
lineWidth+= fInput.getLeadingImageWidth();
textWidth= Math.max(textWidth, lineWidth);
}
bounds.width= textWidth;
fTextLayout.setText(""); //$NON-NLS-1$
int minWidth= bounds.width;
height= height + bounds.height;
// Add some air to accommodate for different browser renderings
minWidth+= 15;
height+= 15;
// Apply max size constraints
if (sizeConstraints != null) {
if (sizeConstraints.x != SWT.DEFAULT)
minWidth= Math.min(sizeConstraints.x, minWidth + trim.width);
if (sizeConstraints.y != SWT.DEFAULT)
height= Math.min(sizeConstraints.y, height);
}
// Ensure minimal size
int width= Math.max(MIN_WIDTH, minWidth);
height= Math.max(MIN_HEIGHT, height);
return new Point(width, height);
}
/*
* @see org.eclipse.jface.text.IInformationControlExtension3#computeTrim()
*/
public Rectangle computeTrim() {
Rectangle trim= super.computeTrim();
if (isResizable()) {
boolean RTL= (getShell().getStyle() & SWT.RIGHT_TO_LEFT) != 0;
if (RTL) {
trim.x-= fgScrollBarSize.x;
}
trim.width+= fgScrollBarSize.x;
trim.height+= fgScrollBarSize.y;
}
return trim;
}
/**
* Adds the listener to the collection of listeners who will be
* notified when the current location has changed or is about to change.
*
* @param listener the location listener
* @since 3.4
*/
public void addLocationListener(LocationListener listener) {
fBrowser.addLocationListener(listener);
}
/*
* @see IInformationControl#setForegroundColor(Color)
*/
public void setForegroundColor(Color foreground) {
super.setForegroundColor(foreground);
fBrowser.setForeground(foreground);
}
/*
* @see IInformationControl#setBackgroundColor(Color)
*/
public void setBackgroundColor(Color background) {
super.setBackgroundColor(background);
fBrowser.setBackground(background);
}
/*
* @see IInformationControlExtension#hasContents()
*/
public boolean hasContents() {
return fBrowserHasContent;
}
/**
* Adds a listener for input changes to this input change provider.
* Has no effect if an identical listener is already registered.
*
* @param inputChangeListener the listener to add
* @since 3.4
*/
public void addInputChangeListener(IInputChangedListener inputChangeListener) {
Assert.isNotNull(inputChangeListener);
fInputChangeListeners.add(inputChangeListener);
}
/**
* Removes the given input change listener from this input change provider.
* Has no effect if an identical listener is not registered.
*
* @param inputChangeListener the listener to remove
* @since 3.4
*/
public void removeInputChangeListener(IInputChangedListener inputChangeListener) {
fInputChangeListeners.remove(inputChangeListener);
}
/*
* @see org.eclipse.jface.text.IDelayedInputChangeProvider#setDelayedInputChangeListener(org.eclipse.jface.text.IInputChangedListener)
* @since 3.4
*/
public void setDelayedInputChangeListener(IInputChangedListener inputChangeListener) {
fDelayedInputChangeListener= inputChangeListener;
}
/**
* Tells whether a delayed input change listener is registered.
*
* @return <code>true</code> iff a delayed input change
* listener is currently registered
* @since 3.4
*/
public boolean hasDelayedInputChangeListener() {
return fDelayedInputChangeListener != null;
}
/**
* Notifies listeners of a delayed input change.
*
* @param newInput the new input, or <code>null</code> to request cancellation
* @since 3.4
*/
public void notifyDelayedInputChange(Object newInput) {
if (fDelayedInputChangeListener != null)
fDelayedInputChangeListener.inputChanged(newInput);
}
/*
* @see java.lang.Object#toString()
* @since 3.4
*/
public String toString() {
String style= (getShell().getStyle() & SWT.RESIZE) == 0 ? "fixed" : "resizeable"; //$NON-NLS-1$ //$NON-NLS-2$
return super.toString() + " - style: " + style; //$NON-NLS-1$
}
/**
* @return the current browser input or <code>null</code>
*/
public BrowserInformationControlInput getInput() {
return fInput;
}
/*
* @see org.eclipse.jface.text.IInformationControlExtension5#computeSizeConstraints(int, int)
*/
public Point computeSizeConstraints(int widthInChars, int heightInChars) {
if (fSymbolicFontName == null)
return null;
GC gc= new GC(fBrowser);
Font font= fSymbolicFontName == null ? JFaceResources.getDialogFont() : JFaceResources.getFont(fSymbolicFontName);
gc.setFont(font);
int width= gc.getFontMetrics().getAverageCharWidth();
int height= gc.getFontMetrics().getHeight();
gc.dispose();
return new Point(widthInChars * width, heightInChars * height);
}
}