update/org.eclipse.update.ui.forms/src/org/eclipse/update/ui/forms/HyperlinkHandler.java

package org.eclipse.update.ui.forms;
/*
 * (c) Copyright IBM Corp. 2000, 2001.
 * All Rights Reserved.
 */

import org.eclipse.swt.widgets.*;
import org.eclipse.swt.events.*;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.graphics.*;
import java.util.*;
import org.eclipse.swt.*;

public class HyperlinkHandler implements MouseListener, 
										 MouseTrackListener, 
										 SelectionListener,
										 PaintListener {
	public static final int UNDERLINE_NEVER = 1;
	public static final int UNDERLINE_ROLLOVER = 2;
	public static final int UNDERLINE_ALWAYS = 3;

	private Cursor hyperlinkCursor;
	private Cursor busyCursor;
	private boolean hyperlinkCursorUsed=true;
	private int hyperlinkUnderlineMode=UNDERLINE_ALWAYS;
	private Color background;
	private Color foreground;
	private Color activeBackground;
	private Color activeForeground;
	private Hashtable hyperlinkListeners;
	private Control lastActivated;
	private Control lastEntered;

public HyperlinkHandler() {
	hyperlinkListeners = new Hashtable();
	hyperlinkCursor = new Cursor(Display.getCurrent(), SWT.CURSOR_HAND);
	busyCursor = new Cursor(Display.getCurrent(), SWT.CURSOR_WAIT);
}
public void dispose() {
	hyperlinkCursor.dispose();
	busyCursor.dispose();
}
public Color getActiveBackground() {
	return activeBackground;
}
public Color getActiveForeground() {
	return activeForeground;
}
public Color getBackground() {
	return background;
}
public Cursor getBusyCursor() {
	return busyCursor;
}
public Color getForeground() {
	return foreground;
}
public Cursor getHyperlinkCursor() {
	return hyperlinkCursor;
}
public int getHyperlinkUnderlineMode() {
	return hyperlinkUnderlineMode;
}
public Control getLastLink() {
	return lastActivated;
}
public boolean isHyperlinkCursorUsed() {
	return hyperlinkCursorUsed;
}

public void mouseDoubleClick(MouseEvent e) {
}

public void mouseDown(MouseEvent e) {
	if (e.button == 1)
		return;
	lastActivated = (Control)e.widget;
}
public void mouseEnter(MouseEvent e) {
	Control control = (Control) e.widget;
	linkEntered(control);
}
public void mouseExit(MouseEvent e) {
	Control control = (Control) e.widget;
	linkExited(control);
}
public void mouseHover(MouseEvent e) {
}

public void mouseUp(MouseEvent e) {
	if (e.button != 1)
		return;
	linkActivated((Control)e.widget);
}

public void widgetDefaultSelected(SelectionEvent e) {
	Control link = (Control)e.widget;
	linkActivated(link);
}

public void widgetSelected(SelectionEvent e) {
	Control link = (Control)e.widget;
	SelectableFormLabel l = (SelectableFormLabel)link;
	if (l.getSelection()) linkEntered(link);
	else linkExited(link);
}

private void linkActivated(Control link) {
	IHyperlinkListener action =
		(IHyperlinkListener) hyperlinkListeners.get(link);
	if (action != null) {
		link.setCursor(busyCursor);
		action.linkActivated(link);
		if (!link.isDisposed()) 
	   		link.setCursor(isHyperlinkCursorUsed()?hyperlinkCursor:null);
	}
}

private void linkEntered(Control link) {
	if (lastEntered!=null && lastEntered instanceof SelectableFormLabel) {
		SelectableFormLabel fl = (SelectableFormLabel)lastEntered;
		linkExited(fl);
	}
	if (isHyperlinkCursorUsed())
		link.setCursor(hyperlinkCursor);
	if (activeBackground != null)
		link.setBackground(activeBackground);
	if (activeForeground != null)
		link.setForeground(activeForeground);
	if (hyperlinkUnderlineMode==UNDERLINE_ROLLOVER) underline(link, true);    

	IHyperlinkListener action =
		(IHyperlinkListener) hyperlinkListeners.get(link);
	if (action != null)
		action.linkEntered(link);
	lastEntered = link;
}

private void linkExited(Control link) {
	if (isHyperlinkCursorUsed())
		link.setCursor(null);
	if (hyperlinkUnderlineMode==UNDERLINE_ROLLOVER)
		underline(link, false);
	if (background != null)
		link.setBackground(background);
	if (foreground != null)
		link.setForeground(foreground);
	IHyperlinkListener action =
		(IHyperlinkListener) hyperlinkListeners.get(link);
	if (action != null)
		action.linkExited(link);
	if (lastEntered == link) lastEntered = null;
}

public void paintControl(PaintEvent e) {
	Control label = (Control) e.widget;
	if (hyperlinkUnderlineMode == UNDERLINE_ALWAYS)
		HyperlinkHandler.underline(label, true);
}

public void registerHyperlink(Control control, IHyperlinkListener listener) {
	if (background != null)
		control.setBackground(background);
	if (foreground != null)
		control.setForeground(foreground);
	control.addMouseListener(this);
	control.addMouseTrackListener(this);
	if (hyperlinkUnderlineMode == UNDERLINE_ALWAYS && control instanceof Label)
		control.addPaintListener(this);
	if (control instanceof SelectableFormLabel) {
		SelectableFormLabel sl = (SelectableFormLabel)control;
		sl.addSelectionListener(this);
		if (hyperlinkUnderlineMode == UNDERLINE_ALWAYS)
			sl.setUnderlined(true);
	}
	hyperlinkListeners.put(control, listener);
	removeDisposedLinks();
}
private void removeDisposedLinks() {
	for (Enumeration keys = hyperlinkListeners.keys(); keys.hasMoreElements();) {
		Control control = (Control)keys.nextElement();
		if (control.isDisposed()) {
			hyperlinkListeners.remove(control);
		}
	}
}

public void reset() {
	hyperlinkListeners.clear();
}

public void setActiveBackground(Color newActiveBackground) {
	activeBackground = newActiveBackground;
}
public void setActiveForeground(Color newActiveForeground) {
	activeForeground = newActiveForeground;
}
public void setBackground(Color newBackground) {
	background = newBackground;
}
public void setForeground(Color newForeground) {
	foreground = newForeground;
}
public void setHyperlinkCursorUsed(boolean newHyperlinkCursorUsed) {
	hyperlinkCursorUsed = newHyperlinkCursorUsed;
}
public void setHyperlinkUnderlineMode(int newHyperlinkUnderlineMode) {
	hyperlinkUnderlineMode = newHyperlinkUnderlineMode;
}
public static void underline(Control control, boolean inside) {
	if (control instanceof SelectableFormLabel) {
		SelectableFormLabel l = (SelectableFormLabel)control;
		l.setUnderlined(inside);
		l.redraw();
		return;
	}
	if (!(control instanceof Label))
		return;
	Composite parent = control.getParent();
	Rectangle bounds = control.getBounds();
	GC gc = new GC(parent);
	Color color = inside? control.getForeground() : control.getBackground();
	gc.setForeground(color);
	int y = bounds.y + bounds.height;
	gc.drawLine(bounds.x, y, bounds.x+bounds.width, y);
	gc.dispose();
}



}