/**
* <copyright>
* </copyright>
*
*
*/
package org.emftext.language.java.resource.java.ui;
import java.io.IOException;
import java.io.StringReader;
import java.util.Iterator;
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;
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.events.KeyEvent;
import org.eclipse.swt.events.KeyListener;
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;
/**
* <p>
* Displays HTML information in a {@link Browser} widget.
* </p>
* <p>
* <p>
* </p>
* <p>
* This IInformationControlExtension2 expects {@link #setInput(Object)} to be
* called with an argument of type BrowserInformationControlInput.
* </p>
* <p>
* </p>
* </p>
* <p>
* <p>Moved into this package from
* <code>org.eclipse.jface.internal.text.revisions</code>.</p>
* </p>
* <p>
* <p>This class may be instantiated; it is not intended to be subclassed.</p>
* </p>
* <p>
* <p>Current problems:
* </p>
* <p>
* <ul>
* </p>
* <p>
* <li>the size computation is too small</li>
* </p>
* <p>
* <li>focusLost event is not sent - see
* https://bugs.eclipse.org/bugs/show_bug.cgi?id=84532</li>
* </p>
* <p>
* </ul>
* </p>
* <p>
* </p>
* </p>
*
* @since 3.2
*/
public class JavaBrowserInformationControl extends AbstractInformationControl implements IInformationControlExtension2, IDelayedInputChangeProvider {
/**
* <p>
* Tells whether the SWT Browser widget and hence this information control is
* available.
* </p>
*
* @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.
*/
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
*/
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 org.emftext.language.java.resource.java.ui.JavaDocBrowserInformationControlInput fInput;
/**
* <code>true</code> iff the browser has completed loading of the last input set
* via {@link #setInformation(String)}.
*/
private boolean fCompleted = false;
/**
* The listener to be notified when a delayed location changing event happened.
*/
private IInputChangedListener fDelayedInputChangeListener;
/**
* The listeners to be notified when the input changed.
*/
private ListenerList fInputChangeListeners = new ListenerList(ListenerList.IDENTITY);
/**
* The symbolic name of the font used for size computations, or <code>null</code>
* to use dialog font.
*/
private final String fSymbolicFontName;
/**
* <p>
* Creates a browser information control with the given shell as parent.
* </p>
*
* @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
*/
public JavaBrowserInformationControl(Shell parent, String symbolicFontName, boolean resizable) {
super(parent, resizable);
fSymbolicFontName= symbolicFontName;
create();
}
/**
* <p>
* Creates a browser information control with the given shell as parent.
* </p>
*
* @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
*/
public JavaBrowserInformationControl(Shell parent, String symbolicFontName, String statusFieldText) {
super(parent, statusFieldText);
fSymbolicFontName= symbolicFontName;
create();
}
/**
* <p>
* Creates a browser information control with the given shell as parent.
* </p>
*
* @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 JavaBrowserInformationControl(Shell parent, String symbolicFontName, ToolBarManager toolBarManager) {
super(parent, toolBarManager);
fSymbolicFontName= symbolicFontName;
create();
}
/**
*
* @see org.eclipse.jface.text.AbstractInformationControl#createContent(Composite)
*/
protected void createContent(Composite parent) {
fBrowser= new Browser(parent, SWT.NONE);
Display display= getShell().getDisplay();
fBrowser.setForeground(display.getSystemColor(SWT.COLOR_INFO_FOREGROUND));
fBrowser.setBackground(display.getSystemColor(SWT.COLOR_INFO_BACKGROUND));
fBrowser.addKeyListener(new KeyListener() {
public void keyPressed(KeyEvent e) {
if (e.character == 0x1B) // ESC
dispose(); // XXX: Just hide? Would avoid constant recreations.
}
public void keyReleased(KeyEvent e) {}
});
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} This control can handle {@link String}(no handle) and
*/
public void setInput(Object input) {
Assert.isLegal(input == null || input instanceof String || input instanceof org.emftext.language.java.resource.java.ui.JavaDocBrowserInformationControlInput);
if (input instanceof String) {
setInformation((String)input);
return;
}
fInput= (org.emftext.language.java.resource.java.ui.JavaDocBrowserInformationControlInput) input;
String content= null;
if (fInput != null) content= fInput.getHtml();
fBrowserHasContent= content != null && content.length() > 0;
if (!fBrowserHasContent) content= "<html><body ></html>";
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;" };
} else if (RTL && !resizable) {
styles= new String[] { "direction:rtl;", "overflow:hidden;", "word-wrap:break-word;" };
} 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;"*/ };
} else {
styles= new String[] { "overflow:scroll;" };
}
StringBuffer buffer= new StringBuffer(content);
org.emftext.language.java.resource.java.ui.JavaHTMLPrinter.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);
}
}
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())) {
shell.moveAbove(null);
}
super.setVisible(true);
}
/**
*
* @see 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);
}
}
/**
* <p>
* Creates and initializes the text layout used to compute the size hint.
* </p>
*
* @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(" ");
int tabWidth = fTextLayout.getBounds().width;
fTextLayout.setTabs(new int[] {tabWidth});
fTextLayout.setText("");
}
public void dispose() {
if (fTextLayout != null) {
fTextLayout.dispose();
fTextLayout = null;
}
fBrowser = null;
super.dispose();
}
public Point computeSizeHint() {
Point sizeConstraints = getSizeConstraints();
Rectangle trim = computeTrim();
int height = trim.height;
TextPresentation presentation= new TextPresentation();
String text;
try {
text = org.emftext.language.java.resource.java.ui.JavaHTMLPrinter.html2text(new StringReader(fInput.getHtml()), presentation);
} catch (IOException e) {
text = "";
}
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("");
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);
Point windowSize = new Point(width, height);
return windowSize;
}
/**
*
* @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;
}
/**
* <p>
* Adds the listener to the collection of listeners who will be notified when the
* current location has changed or is about to change.
* </p>
*
* @param listener the location listener
*
* @since 3.4
*/
public void addLocationListener(LocationListener listener) {
fBrowser.addLocationListener(listener);
}
public void setForegroundColor(Color foreground) {
super.setForegroundColor(foreground);
fBrowser.setForeground(foreground);
}
public void setBackgroundColor(Color background) {
super.setBackgroundColor(background);
fBrowser.setBackground(background);
}
public boolean hasContents() {
return fBrowserHasContent;
}
/**
* <p>
* Adds a listener for input changes to this input change provider. Has no effect
* if an identical listener is already registered.
* </p>
*
* @param inputChangeListener the listener to add
*
* @since 3.4
*/
public void addInputChangeListener(IInputChangedListener inputChangeListener) {
Assert.isNotNull(inputChangeListener);
fInputChangeListeners.add(inputChangeListener);
}
/**
* <p>
* Removes the given input change listener from this input change provider. Has no
* effect if an identical listener is not registered.
* </p>
*
* @param inputChangeListener the listener to remove
*
* @since 3.4
*/
public void removeInputChangeListener(IInputChangedListener inputChangeListener) {
fInputChangeListeners.remove(inputChangeListener);
}
/**
*
* @see
* IDelayedInputChangeProvider#setDelayedInputChangeListener(IInputChangedListener)
*
* @since 3.4
*/
public void setDelayedInputChangeListener(IInputChangedListener inputChangeListener) {
fDelayedInputChangeListener= inputChangeListener;
}
/**
* <p>
* Tells whether a delayed input change listener is registered.
* </p>
*
* @return <code>true</code> iff a delayed input change listener is currently
* registered
*
* @since 3.4
*/
public boolean hasDelayedInputChangeListener() {
return fDelayedInputChangeListener != null;
}
/**
* <p>
* Notifies listeners of a delayed input change.
* </p>
*
* @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";
return super.toString() + " - style: " + style;
}
/**
*
* @return the current browser input or <code>null</code>
*/
public org.emftext.language.java.resource.java.ui.JavaDocBrowserInformationControlInput 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);
}
}