bundles/org.eclipse.ui.forms/src/org/eclipse/ui/forms/widgets/AbstractHyperlink.java - platform/eclipse.platform.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2007 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.ui.forms.widgets;

 import org.eclipse.core.runtime.ListenerList;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.accessibility.ACC;
 import org.eclipse.swt.events.PaintEvent;
 import org.eclipse.swt.events.PaintListener;
 import org.eclipse.swt.graphics.GC;
 import org.eclipse.swt.graphics.Point;
 import org.eclipse.swt.graphics.Rectangle;
 import org.eclipse.swt.widgets.Canvas;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Event;
 import org.eclipse.swt.widgets.Listener;
 import org.eclipse.ui.forms.events.HyperlinkEvent;
 import org.eclipse.ui.forms.events.IHyperlinkListener;
 import org.eclipse.ui.internal.forms.widgets.FormsResources;

 /**
  * This is the base class for custom hyperlink widget. It is responsible for
  * processing mouse and keyboard events, and converting them into unified
  * hyperlink events. Subclasses are responsible for rendering the hyperlink in
  * the client area.
  *
  * @since 3.0
  */
 public abstract class AbstractHyperlink extends Canvas {
 	private boolean hasFocus;
 	boolean paintFocus=true;

 	/*
 	 * Armed link is one that will activate on a mouse up event, i.e.
 	 * it has received a mouse down and mouse still on top of it.
 	 */
 	private boolean armed;

 	private ListenerList listeners;

 	/**
 	 * Amount of the margin width around the hyperlink (default is 1).
 	 */
 	protected int marginWidth = 1;

 	/**
 	 * Amount of the margin height around the hyperlink (default is 1).
 	 */
 	protected int marginHeight = 1;

 	/**
 	 * Creates a new hyperlink in the provided parent.
 	 *
 	 * @param parent
 	 *            the control parent
 	 * @param style
 	 *            the widget style
 	 */
 	public AbstractHyperlink(Composite parent, int style) {
 		super(parent, style);
 		addListener(SWT.KeyDown, new Listener() {
 			public void handleEvent(Event e) {
 				if (e.character == '\r') {
 					handleActivate(e);
 				}
 			}
 		});
 		addPaintListener(new PaintListener() {
 			public void paintControl(PaintEvent e) {
 				paint(e);
 			}
 		});
 		addListener(SWT.Traverse, new Listener() {
 			public void handleEvent(Event e) {
 				switch (e.detail) {
 				case SWT.TRAVERSE_PAGE_NEXT:
 				case SWT.TRAVERSE_PAGE_PREVIOUS:
 				case SWT.TRAVERSE_ARROW_NEXT:
 				case SWT.TRAVERSE_ARROW_PREVIOUS:
 				case SWT.TRAVERSE_RETURN:
 					e.doit = false;
 					return;
 				}
 				e.doit = true;
 			}
 		});
 		Listener listener = new Listener() {
 			public void handleEvent(Event e) {
 				switch (e.type) {
 				case SWT.FocusIn:
 					hasFocus = true;
 					handleEnter(e);
 					break;
 				case SWT.FocusOut:
 					hasFocus = false;
 					handleExit(e);
 					break;
 				case SWT.DefaultSelection:
 					handleActivate(e);
 					break;
 				case SWT.MouseEnter:
 					handleEnter(e);
 					break;
 				case SWT.MouseExit:
 					handleExit(e);
 					break;
 				case SWT.MouseDown:
 					handleMouseDown(e);
 					break;
 				case SWT.MouseUp:
 					handleMouseUp(e);
 					break;
 				case SWT.MouseMove:
 					handleMouseMove(e);
 					break;
 				}
 			}
 		};
 		addListener(SWT.MouseEnter, listener);
 		addListener(SWT.MouseExit, listener);
 		addListener(SWT.MouseDown, listener);
 		addListener(SWT.MouseUp, listener);
 		addListener(SWT.MouseMove, listener);
 		addListener(SWT.FocusIn, listener);
 		addListener(SWT.FocusOut, listener);
 		setCursor(FormsResources.getHandCursor());
 	}

 	/**
 	 * Adds the event listener to this hyperlink.
 	 *
 	 * @param listener
 	 *            the event listener to add
 	 */
 	public void addHyperlinkListener(IHyperlinkListener listener) {
 		if (listeners == null)
 			listeners = new ListenerList();
 		listeners.add(listener);
 	}

 	/**
 	 * Removes the event listener from this hyperlink.
 	 *
 	 * @param listener
 	 *            the event listener to remove
 	 */
 	public void removeHyperlinkListener(IHyperlinkListener listener) {
 		if (listeners == null)
 			return;
 		listeners.remove(listener);
 	}

 	/**
 	 * Returns the selection state of the control. When focus is gained, the
 	 * state will be <samp>true </samp>; it will switch to <samp>false </samp>
 	 * when the control looses focus.
 	 *
 	 * @return <code>true</code> if the widget has focus, <code>false</code>
 	 *         otherwise.
 	 */
 	public boolean getSelection() {
 		return hasFocus;
 	}

 	/**
 	 * Called when hyperlink is entered. Subclasses that override this method
 	 * must call 'super'.
 	 */
 	protected void handleEnter(Event e) {
 		redraw();
 		if (listeners == null)
 			return;
 		int size = listeners.size();
 		HyperlinkEvent he = new HyperlinkEvent(this, getHref(), getText(),
 				e.stateMask);
 		Object[] listenerList = listeners.getListeners();
 		for (int i = 0; i < size; i++) {
 			IHyperlinkListener listener = (IHyperlinkListener) listenerList[i];
 			listener.linkEntered(he);
 		}
 	}

 	/**
 	 * Called when hyperlink is exited. Subclasses that override this method
 	 * must call 'super'.
 	 */
 	protected void handleExit(Event e) {
 		// disarm the link; won't activate on mouseup
 		armed = false;
 		redraw();
 		if (listeners == null)
 			return;
 		int size = listeners.size();
 		HyperlinkEvent he = new HyperlinkEvent(this, getHref(), getText(),
 				e.stateMask);
 		Object[] listenerList = listeners.getListeners();
 		for (int i = 0; i < size; i++) {
 			IHyperlinkListener listener = (IHyperlinkListener) listenerList[i];
 			listener.linkExited(he);
 		}
 	}

 	/**
 	 * Called when hyperlink has been activated. Subclasses that override this
 	 * method must call 'super'.
 	 */
 	protected void handleActivate(Event e) {
 		// disarm link, back to normal state
 		armed = false;
 		getAccessible().setFocus(ACC.CHILDID_SELF);
 		if (listeners == null)
 			return;
 		int size = listeners.size();
 		setCursor(FormsResources.getBusyCursor());
 		HyperlinkEvent he = new HyperlinkEvent(this, getHref(), getText(),
 				e.stateMask);
 		Object[] listenerList = listeners.getListeners();
 		for (int i = 0; i < size; i++) {
 			IHyperlinkListener listener = (IHyperlinkListener) listenerList[i];
 			listener.linkActivated(he);
 		}
 		if (!isDisposed())
 			setCursor(FormsResources.getHandCursor());
 	}

 	/**
 	 * Sets the object associated with this hyperlink. Concrete implementation
 	 * of this class can use if to store text, URLs or model objects that need
 	 * to be processed on hyperlink events.
 	 *
 	 * @param href
 	 *            the hyperlink object reference
 	 */
 	public void setHref(Object href) {
 		setData("href", href); //$NON-NLS-1$
 	}

 	/**
 	 * Returns the object associated with this hyperlink.
 	 *
 	 * @see #setHref
 	 * @return the hyperlink object reference
 	 */
 	public Object getHref() {
 		return getData("href"); //$NON-NLS-1$
 	}

 	/**
 	 * Returns the textual representation of this hyperlink suitable for showing
 	 * in tool tips or on the status line.
 	 *
 	 * @return the hyperlink text
 	 */
 	public String getText() {
 		return getToolTipText();
 	}

 	/**
 	 * Paints the hyperlink as a reaction to the provided paint event.
 	 *
 	 * @param gc
 	 *            graphic context
 	 */
 	protected abstract void paintHyperlink(GC gc);

 	/**
 	 * Paints the control as a reaction to the provided paint event.
 	 *
 	 * @param e
 	 *            the paint event
 	 */
 	protected void paint(PaintEvent e) {
 		GC gc = e.gc;
 		Rectangle clientArea = getClientArea();
 		if (clientArea.width == 0 || clientArea.height == 0)
 			return;
 		paintHyperlink(gc);
 		if (paintFocus && hasFocus) {
 			Rectangle carea = getClientArea();
 			gc.setForeground(getForeground());
 			gc.drawFocus(0, 0, carea.width, carea.height);
 		}
 	}

 	private void handleMouseDown(Event e) {
 		if (e.button != 1)
 			return;
 		// armed and ready to activate on mouseup
 		armed = true;
 	}

 	private void handleMouseUp(Event e) {
 		if (!armed || e.button != 1)
 			return;
 		Point size = getSize();
 		// Filter out mouse up events outside
 		// the link. This can happen when mouse is
 		// clicked, dragged outside the link, then
 		// released.
 		if (e.x < 0)
 			return;
 		if (e.y < 0)
 			return;
 		if (e.x >= size.x)
 			return;
 		if (e.y >= size.y)
 			return;
 		handleActivate(e);
 	}

 	private void handleMouseMove(Event e) {
 		// disarm link if we move out of bounds
 		if (armed) {
 			Point size = getSize();
 			armed = (e.x >= 0 && e.y >= 0 && e.x < size.x && e.y < size.y);
 		}
 	}

 	/*
 	 * (non-Javadoc)
 	 * @see org.eclipse.swt.widgets.Control#setEnabled(boolean)
 	 */

 	public void setEnabled (boolean enabled) {
 		super.setEnabled(enabled);
 		redraw();
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2007 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.ui.forms.widgets;

	import org.eclipse.core.runtime.ListenerList;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.accessibility.ACC;
	import org.eclipse.swt.events.PaintEvent;
	import org.eclipse.swt.events.PaintListener;
	import org.eclipse.swt.graphics.GC;
	import org.eclipse.swt.graphics.Point;
	import org.eclipse.swt.graphics.Rectangle;
	import org.eclipse.swt.widgets.Canvas;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Event;
	import org.eclipse.swt.widgets.Listener;
	import org.eclipse.ui.forms.events.HyperlinkEvent;
	import org.eclipse.ui.forms.events.IHyperlinkListener;
	import org.eclipse.ui.internal.forms.widgets.FormsResources;

	/**
	* This is the base class for custom hyperlink widget. It is responsible for
	* processing mouse and keyboard events, and converting them into unified
	* hyperlink events. Subclasses are responsible for rendering the hyperlink in
	* the client area.
	*
	* @since 3.0
	*/
	public abstract class AbstractHyperlink extends Canvas {
	private boolean hasFocus;
	boolean paintFocus=true;

	/*
	* Armed link is one that will activate on a mouse up event, i.e.
	* it has received a mouse down and mouse still on top of it.
	*/
	private boolean armed;

	private ListenerList listeners;

	/**
	* Amount of the margin width around the hyperlink (default is 1).
	*/
	protected int marginWidth = 1;

	/**
	* Amount of the margin height around the hyperlink (default is 1).
	*/
	protected int marginHeight = 1;

	/**
	* Creates a new hyperlink in the provided parent.
	*
	* @param parent
	* the control parent
	* @param style
	* the widget style
	*/
	public AbstractHyperlink(Composite parent, int style) {
	super(parent, style);
	addListener(SWT.KeyDown, new Listener() {
	public void handleEvent(Event e) {
	if (e.character == '\r') {
	handleActivate(e);
	}
	}
	});
	addPaintListener(new PaintListener() {
	public void paintControl(PaintEvent e) {
	paint(e);
	}
	});
	addListener(SWT.Traverse, new Listener() {
	public void handleEvent(Event e) {
	switch (e.detail) {
	case SWT.TRAVERSE_PAGE_NEXT:
	case SWT.TRAVERSE_PAGE_PREVIOUS:
	case SWT.TRAVERSE_ARROW_NEXT:
	case SWT.TRAVERSE_ARROW_PREVIOUS:
	case SWT.TRAVERSE_RETURN:
	e.doit = false;
	return;
	}
	e.doit = true;
	}
	});
	Listener listener = new Listener() {
	public void handleEvent(Event e) {
	switch (e.type) {
	case SWT.FocusIn:
	hasFocus = true;
	handleEnter(e);
	break;
	case SWT.FocusOut:
	hasFocus = false;
	handleExit(e);
	break;
	case SWT.DefaultSelection:
	handleActivate(e);
	break;
	case SWT.MouseEnter:
	handleEnter(e);
	break;
	case SWT.MouseExit:
	handleExit(e);
	break;
	case SWT.MouseDown:
	handleMouseDown(e);
	break;
	case SWT.MouseUp:
	handleMouseUp(e);
	break;
	case SWT.MouseMove:
	handleMouseMove(e);
	break;
	}
	}
	};
	addListener(SWT.MouseEnter, listener);
	addListener(SWT.MouseExit, listener);
	addListener(SWT.MouseDown, listener);
	addListener(SWT.MouseUp, listener);
	addListener(SWT.MouseMove, listener);
	addListener(SWT.FocusIn, listener);
	addListener(SWT.FocusOut, listener);
	setCursor(FormsResources.getHandCursor());
	}

	/**
	* Adds the event listener to this hyperlink.
	*
	* @param listener
	* the event listener to add
	*/
	public void addHyperlinkListener(IHyperlinkListener listener) {
	if (listeners == null)
	listeners = new ListenerList();
	listeners.add(listener);
	}

	/**
	* Removes the event listener from this hyperlink.
	*
	* @param listener
	* the event listener to remove
	*/
	public void removeHyperlinkListener(IHyperlinkListener listener) {
	if (listeners == null)
	return;
	listeners.remove(listener);
	}

	/**
	* Returns the selection state of the control. When focus is gained, the
	* state will be <samp>true </samp>; it will switch to <samp>false </samp>
	* when the control looses focus.
	*
	* @return <code>true</code> if the widget has focus, <code>false</code>
	* otherwise.
	*/
	public boolean getSelection() {
	return hasFocus;
	}

	/**
	* Called when hyperlink is entered. Subclasses that override this method
	* must call 'super'.
	*/
	protected void handleEnter(Event e) {
	redraw();
	if (listeners == null)
	return;
	int size = listeners.size();
	HyperlinkEvent he = new HyperlinkEvent(this, getHref(), getText(),
	e.stateMask);
	Object[] listenerList = listeners.getListeners();
	for (int i = 0; i < size; i++) {
	IHyperlinkListener listener = (IHyperlinkListener) listenerList[i];
	listener.linkEntered(he);
	}
	}

	/**
	* Called when hyperlink is exited. Subclasses that override this method
	* must call 'super'.
	*/
	protected void handleExit(Event e) {
	// disarm the link; won't activate on mouseup
	armed = false;
	redraw();
	if (listeners == null)
	return;
	int size = listeners.size();
	HyperlinkEvent he = new HyperlinkEvent(this, getHref(), getText(),
	e.stateMask);
	Object[] listenerList = listeners.getListeners();
	for (int i = 0; i < size; i++) {
	IHyperlinkListener listener = (IHyperlinkListener) listenerList[i];
	listener.linkExited(he);
	}
	}

	/**
	* Called when hyperlink has been activated. Subclasses that override this
	* method must call 'super'.
	*/
	protected void handleActivate(Event e) {
	// disarm link, back to normal state
	armed = false;
	getAccessible().setFocus(ACC.CHILDID_SELF);
	if (listeners == null)
	return;
	int size = listeners.size();
	setCursor(FormsResources.getBusyCursor());
	HyperlinkEvent he = new HyperlinkEvent(this, getHref(), getText(),
	e.stateMask);
	Object[] listenerList = listeners.getListeners();
	for (int i = 0; i < size; i++) {
	IHyperlinkListener listener = (IHyperlinkListener) listenerList[i];
	listener.linkActivated(he);
	}
	if (!isDisposed())
	setCursor(FormsResources.getHandCursor());
	}

	/**
	* Sets the object associated with this hyperlink. Concrete implementation
	* of this class can use if to store text, URLs or model objects that need
	* to be processed on hyperlink events.
	*
	* @param href
	* the hyperlink object reference
	*/
	public void setHref(Object href) {
	setData("href", href); //$NON-NLS-1$
	}

	/**
	* Returns the object associated with this hyperlink.
	*
	* @see #setHref
	* @return the hyperlink object reference
	*/
	public Object getHref() {
	return getData("href"); //$NON-NLS-1$
	}

	/**
	* Returns the textual representation of this hyperlink suitable for showing
	* in tool tips or on the status line.
	*
	* @return the hyperlink text
	*/
	public String getText() {
	return getToolTipText();
	}

	/**
	* Paints the hyperlink as a reaction to the provided paint event.
	*
	* @param gc
	* graphic context
	*/
	protected abstract void paintHyperlink(GC gc);

	/**
	* Paints the control as a reaction to the provided paint event.
	*
	* @param e
	* the paint event
	*/
	protected void paint(PaintEvent e) {
	GC gc = e.gc;
	Rectangle clientArea = getClientArea();
	if (clientArea.width == 0 \|\| clientArea.height == 0)
	return;
	paintHyperlink(gc);
	if (paintFocus && hasFocus) {
	Rectangle carea = getClientArea();
	gc.setForeground(getForeground());
	gc.drawFocus(0, 0, carea.width, carea.height);
	}
	}

	private void handleMouseDown(Event e) {
	if (e.button != 1)
	return;
	// armed and ready to activate on mouseup
	armed = true;
	}

	private void handleMouseUp(Event e) {
	if (!armed \|\| e.button != 1)
	return;
	Point size = getSize();
	// Filter out mouse up events outside
	// the link. This can happen when mouse is
	// clicked, dragged outside the link, then
	// released.
	if (e.x < 0)
	return;
	if (e.y < 0)
	return;
	if (e.x >= size.x)
	return;
	if (e.y >= size.y)
	return;
	handleActivate(e);
	}

	private void handleMouseMove(Event e) {
	// disarm link if we move out of bounds
	if (armed) {
	Point size = getSize();
	armed = (e.x >= 0 && e.y >= 0 && e.x < size.x && e.y < size.y);
	}
	}

	/*
	* (non-Javadoc)
	* @see org.eclipse.swt.widgets.Control#setEnabled(boolean)
	*/

	public void setEnabled (boolean enabled) {
	super.setEnabled(enabled);
	redraw();
	}
	}