bundles/org.eclipse.swt/Eclipse SWT/carbon/org/eclipse/swt/widgets/Sash.java - platform/eclipse.platform.swt - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2003 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Common Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/cpl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.swt.widgets;


 import org.eclipse.swt.internal.carbon.OS;
 import org.eclipse.swt.internal.carbon.Rect;

 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;
 import org.eclipse.swt.events.*;

 /**
  * Instances of the receiver represent a selectable user interface object
  * that allows the user to drag a rubber banded outline of the sash within
  * the parent control.
  * <dl>
  * <dt><b>Styles:</b></dt>
  * <dd>HORIZONTAL, VERTICAL</dd>
  * <dt><b>Events:</b></dt>
  * <dd>Selection</dd>
  * </dl>
  * <p>
  * Note: Only one of the styles HORIZONTAL and VERTICAL may be specified.
  * </p><p>
  * IMPORTANT: This class is intended to be subclassed <em>only</em>
  * within the SWT implementation.
  * </p>
  */
 public class Sash extends Control {
 	Cursor sizeCursor;
 	int startX, startY, lastX, lastY;
 	private final static int INCREMENT = 1;
 	private final static int PAGE_INCREMENT = 9;

 /**
  * Constructs a new instance of this class given its parent
  * and a style value describing its behavior and appearance.
  * <p>
  * The style value is either one of the style constants defined in
  * class <code>SWT</code> which is applicable to instances of this
  * class, or must be built by <em>bitwise OR</em>'ing together
  * (that is, using the <code>int</code> "|" operator) two or more
  * of those <code>SWT</code> style constants. The class description
  * lists the style constants that are applicable to the class.
  * Style bits are also inherited from superclasses.
  * </p>
  *
  * @param parent a composite control which will be the parent of the new instance (cannot be null)
  * @param style the style of control to construct
  *
  * @exception IllegalArgumentException <ul>
  *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
  * </ul>
  * @exception SWTException <ul>
  *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
  *    <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
  * </ul>
  *
  * @see SWT#HORIZONTAL
  * @see SWT#VERTICAL
  * @see Widget#checkSubclass
  * @see Widget#getStyle
  */
 public Sash (Composite parent, int style) {
 	super (parent, checkStyle (style));
 	int cursorStyle = (style & SWT.VERTICAL) != 0 ? SWT.CURSOR_SIZEWE : SWT.CURSOR_SIZENS;
 	sizeCursor = new Cursor (display, cursorStyle);
 }

 /**
  * Adds the listener to the collection of listeners who will
  * be notified when the control is selected, by sending
  * it one of the messages defined in the <code>SelectionListener</code>
  * interface.
  * <p>
  * When <code>widgetSelected</code> is called, the x, y, width, and height fields of the event object are valid.
  * If the reciever is being dragged, the event object detail field contains the value <code>SWT.DRAG</code>.
  * <code>widgetDefaultSelected</code> is not called.
  * </p>
  *
  * @param listener the listener which should be notified
  *
  * @exception IllegalArgumentException <ul>
  *    <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
  * </ul>
  * @exception SWTException <ul>
  *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
  *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
  * </ul>
  *
  * @see SelectionListener
  * @see #removeSelectionListener
  * @see SelectionEvent
  */
 public void addSelectionListener(SelectionListener listener) {
 	checkWidget();
 	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
 	TypedListener typedListener = new TypedListener(listener);
 	addListener(SWT.Selection,typedListener);
 	addListener(SWT.DefaultSelection,typedListener);
 }

 static int checkStyle (int style) {
 	return checkBits (style, SWT.HORIZONTAL, SWT.VERTICAL, 0, 0, 0, 0);
 }

 public Point computeSize (int wHint, int hHint, boolean changed) {
 	checkWidget();
 	int width = 0, height = 0;
 	if ((style & SWT.HORIZONTAL) != 0) {
 		width += DEFAULT_WIDTH;  height += 5;
 	} else {
 		width += 5; height += DEFAULT_HEIGHT;
 	}
 	if (wHint != SWT.DEFAULT) width = wHint;
 	if (hHint != SWT.DEFAULT) height = hHint;
 	return new Point (width, height);
 }

 void createHandle () {
 	int features = OS.kControlSupportsFocus;
 	int [] outControl = new int [1];
 	int window = OS.GetControlOwner (parent.handle);
 	OS.CreateUserPaneControl (window, null, features, outControl);
 	if (outControl [0] == 0) error (SWT.ERROR_NO_HANDLES);
 	handle = outControl [0];
 }

 void drawBackground (int control) {
 	drawBackground (control, background);
 }

 int kEventControlClick (int nextHandler, int theEvent, int userData) {
 	int result = super.kEventControlClick (nextHandler, theEvent, userData);
 	if (result == OS.noErr) return result;
 	if (!isEnabled ()) return OS.noErr;
 	return result;
 }

 int kEventControlSetCursor (int nextHandler, int theEvent, int userData) {
 	int result = super.kEventControlSetCursor (nextHandler, theEvent, userData);
 	if (result == OS.noErr) return result;
 	display.setCursor (sizeCursor.handle);
 	return OS.noErr;
 }

 int kEventMouseDown (int nextHandler, int theEvent, int userData) {
 	int result = super.kEventMouseDown (nextHandler, theEvent, userData);
 	if (result == OS.noErr) return result;

 	Rect rect = new Rect ();
 	OS.GetControlBounds (handle, rect);
 	int startX = rect.left;
 	int startY = rect.top;
 	int width = rect.right - rect.left;
 	int height = rect.bottom - rect.top;
 	OS.GetControlBounds (parent.handle, rect);
 	Event event = new Event ();
 	event.x = startX -= rect.left;
 	event.y = startY -= rect.top;
 	event.width = width;
 	event.height = height;
 	sendEvent (SWT.Selection, event);
 	if (isDisposed ()) return result;
 	if (!event.doit) return result;

 	int sizeof = org.eclipse.swt.internal.carbon.Point.sizeof;
 	org.eclipse.swt.internal.carbon.Point pt = new org.eclipse.swt.internal.carbon.Point ();
 	OS.GetEventParameter (theEvent, OS.kEventParamMouseLocation, OS.typeQDPoint, null, sizeof, null, pt);
 	int window = OS.GetControlOwner (handle);
 	OS.GetWindowBounds (window, (short) OS.kWindowContentRgn, rect);
 	int offsetX = pt.h - rect.left;
 	int offsetY = pt.v - rect.top;
 	OS.GetControlBounds (handle, rect);
 	offsetX -= rect.left;
 	offsetY -= rect.top;

 	int port = OS.GetWindowPort (window);
 	int [] outModifiers = new int [1];
 	short [] outResult = new short [1];
 	org.eclipse.swt.internal.carbon.Point outPt = new org.eclipse.swt.internal.carbon.Point ();
 	while (outResult [0] != OS.kMouseTrackingMouseUp) {
 		OS.TrackMouseLocationWithOptions (port, 0, OS.kEventDurationForever, outPt, outModifiers, outResult);
 		switch (outResult [0]) {
 			case OS.kMouseTrackingMouseDown:
 			case OS.kMouseTrackingMouseUp:
 			case OS.kMouseTrackingMouseDragged: {
 				OS.GetControlBounds (parent.handle, rect);
 				int x = outPt.h - rect.left;
 				int y = outPt.v - rect.top;
 				int newX = startX, newY = startY;
 				if ((style & SWT.VERTICAL) != 0) {
 					int clientWidth = rect.right - rect.left;
 					newX = Math.min (Math.max (0, x - offsetX), clientWidth - width);
 				} else {
 					int clientHeight = rect.bottom - rect.top;
 					newY = Math.min (Math.max (0, y - offsetY), clientHeight - height);
 				}
 				event = new Event ();
 				event.x = newX;
 				event.y = newY;
 				event.width = width;
 				event.height = height;
 				event.detail = 0; //outResult [0] == OS.kMouseTrackingMouseDragged ? SWT.DRAG : 0;
 				sendEvent (SWT.Selection, event);
 				if (isDisposed ()) return result;
 				if (event.doit) {
 					setBounds (newX, newY, width, height);
 					Shell shell = parent.getShell ();
 					shell.update (true);
 				}
 				break;
 			}
 			default:
 				outResult [0] = OS.kMouseTrackingMouseUp;
 				break;
 		}
 	}
 	return result;
 }

 int kEventControlSetFocusPart (int nextHandler, int theEvent, int userData) {
 	int result = super.kEventControlSetFocusPart (nextHandler, theEvent, userData);
 	if (result == OS.noErr) return result;
 	Point location = getLocation();
 	lastX = location.x;
 	lastY = location.y;
 	return OS.noErr;
 }

 int kEventTextInputUnicodeForKeyEvent (int nextHandler, int theEvent, int userData) {
 	int result = super.kEventTextInputUnicodeForKeyEvent (nextHandler, theEvent, userData);
 	if (result == OS.noErr) return result;
 	int [] keyboardEvent = new int [1];
 	OS.GetEventParameter (theEvent, OS.kEventParamTextInputSendKeyboardEvent, OS.typeEventRef, null, keyboardEvent.length * 4, null, keyboardEvent);
 	int [] keyCode = new int [1];
 	OS.GetEventParameter (keyboardEvent [0], OS.kEventParamKeyCode, OS.typeUInt32, null, keyCode.length * 4, null, keyCode);
 	switch (keyCode [0]) {
 		case 126: /* Up arrow */
 		case 123: /* Left arrow */
 		case 125: /* Down arrow */
 		case 124: /* Right arrow */ {
 			int xChange = 0, yChange = 0;
 			int stepSize = PAGE_INCREMENT;
 			int [] modifiers = new int [1];
 			OS.GetEventParameter (theEvent, OS.kEventParamKeyModifiers, OS.typeUInt32, null, 4, null, modifiers);
 			if ((modifiers [0] & OS.controlKey) != 0) stepSize = INCREMENT;
 			if ((style & SWT.VERTICAL) != 0) {
 				if (keyCode [0] == 126 || keyCode [0] == 125) break;
 				xChange = keyCode [0] == 123 ? -stepSize : stepSize;
 			} else {
 				if (keyCode [0] == 123 || keyCode [0] == 124) break;
 				yChange = keyCode [0] == 126 ? -stepSize : stepSize;
 			}

 			Rectangle bounds = getBounds ();
 			int width = bounds.width, height = bounds.height;
 			Rectangle parentBounds = parent.getBounds ();
 			int parentWidth = parentBounds.width;
 			int parentHeight = parentBounds.height;
 			int newX = lastX, newY = lastY;
 			if ((style & SWT.VERTICAL) != 0) {
 				newX = Math.min (Math.max (0, lastX + xChange - startX), parentWidth - width);
 			} else {
 				newY = Math.min (Math.max (0, lastY + yChange - startY), parentHeight - height);
 			}
 			if (newX == lastX && newY == lastY) return result;

 			/* The event must be sent because its doit flag is used. */
 			Event event = new Event ();
 			event.x = newX;  event.y = newY;
 			event.width = width;  event.height = height;
 			sendEvent (SWT.Selection, event);

 			/*
 			 * It is possible (but unlikely) that client code could have disposed
 			 * the widget in the selection event.  If this happens end the processing
 			 * of this message by returning.
 			 */
 			if (isDisposed ()) break;
 			if (event.doit) {
 				lastX = event.x;  lastY = event.y;
 				/* Adjust the pointer position */
 				int cursorX = newX;  int cursorY = newY;
 				if ((style & SWT.VERTICAL) != 0) {
 					cursorY += height / 2;
 				} else {
 					cursorX += width / 2;
 				}
 				display.setCursorLocation (parent.toDisplay (cursorX, cursorY));
 			}
 			break;
 		}
 	}

 	return result;
 }

 void releaseWidget () {
 	super.releaseWidget ();
 	if (sizeCursor != null) sizeCursor.dispose ();
 	sizeCursor = null;
 }

 /**
  * Removes the listener from the collection of listeners who will
  * be notified when the control is selected.
  *
  * @param listener the listener which should be notified
  *
  * @exception IllegalArgumentException <ul>
  *    <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
  * </ul>
  * @exception SWTException <ul>
  *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
  *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
  * </ul>
  *
  * @see SelectionListener
  * @see #addSelectionListener
  */
 public void removeSelectionListener(SelectionListener listener) {
 	checkWidget();
 	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
 	if (eventTable == null) return;
 	eventTable.unhook(SWT.Selection, listener);
 	eventTable.unhook(SWT.DefaultSelection,listener);
 }

 int traversalCode (int key, int theEvent) {
 	return 0;
 }

 }
	/*******************************************************************************
	* Copyright (c) 2000, 2003 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Common Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/cpl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.swt.widgets;


	import org.eclipse.swt.internal.carbon.OS;
	import org.eclipse.swt.internal.carbon.Rect;

	import org.eclipse.swt.*;
	import org.eclipse.swt.graphics.*;
	import org.eclipse.swt.events.*;

	/**
	* Instances of the receiver represent a selectable user interface object
	* that allows the user to drag a rubber banded outline of the sash within
	* the parent control.
	* <dl>
	* <dt><b>Styles:</b></dt>
	* <dd>HORIZONTAL, VERTICAL</dd>
	* <dt><b>Events:</b></dt>
	* <dd>Selection</dd>
	* </dl>
	* <p>
	* Note: Only one of the styles HORIZONTAL and VERTICAL may be specified.
	* </p><p>
	* IMPORTANT: This class is intended to be subclassed <em>only</em>
	* within the SWT implementation.
	* </p>
	*/
	public class Sash extends Control {
	Cursor sizeCursor;
	int startX, startY, lastX, lastY;
	private final static int INCREMENT = 1;
	private final static int PAGE_INCREMENT = 9;

	/**
	* Constructs a new instance of this class given its parent
	* and a style value describing its behavior and appearance.
	* <p>
	* The style value is either one of the style constants defined in
	* class <code>SWT</code> which is applicable to instances of this
	* class, or must be built by <em>bitwise OR</em>'ing together
	* (that is, using the <code>int</code> "\|" operator) two or more
	* of those <code>SWT</code> style constants. The class description
	* lists the style constants that are applicable to the class.
	* Style bits are also inherited from superclasses.
	* </p>
	*
	* @param parent a composite control which will be the parent of the new instance (cannot be null)
	* @param style the style of control to construct
	*
	* @exception IllegalArgumentException <ul>
	* <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
	* </ul>
	* @exception SWTException <ul>
	* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
	* <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
	* </ul>
	*
	* @see SWT#HORIZONTAL
	* @see SWT#VERTICAL
	* @see Widget#checkSubclass
	* @see Widget#getStyle
	*/
	public Sash (Composite parent, int style) {
	super (parent, checkStyle (style));
	int cursorStyle = (style & SWT.VERTICAL) != 0 ? SWT.CURSOR_SIZEWE : SWT.CURSOR_SIZENS;
	sizeCursor = new Cursor (display, cursorStyle);
	}

	/**
	* Adds the listener to the collection of listeners who will
	* be notified when the control is selected, by sending
	* it one of the messages defined in the <code>SelectionListener</code>
	* interface.
	* <p>
	* When <code>widgetSelected</code> is called, the x, y, width, and height fields of the event object are valid.
	* If the reciever is being dragged, the event object detail field contains the value <code>SWT.DRAG</code>.
	* <code>widgetDefaultSelected</code> is not called.
	* </p>
	*
	* @param listener the listener which should be notified
	*
	* @exception IllegalArgumentException <ul>
	* <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
	* </ul>
	* @exception SWTException <ul>
	* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
	* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
	* </ul>
	*
	* @see SelectionListener
	* @see #removeSelectionListener
	* @see SelectionEvent
	*/
	public void addSelectionListener(SelectionListener listener) {
	checkWidget();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	TypedListener typedListener = new TypedListener(listener);
	addListener(SWT.Selection,typedListener);
	addListener(SWT.DefaultSelection,typedListener);
	}

	static int checkStyle (int style) {
	return checkBits (style, SWT.HORIZONTAL, SWT.VERTICAL, 0, 0, 0, 0);
	}

	public Point computeSize (int wHint, int hHint, boolean changed) {
	checkWidget();
	int width = 0, height = 0;
	if ((style & SWT.HORIZONTAL) != 0) {
	width += DEFAULT_WIDTH; height += 5;
	} else {
	width += 5; height += DEFAULT_HEIGHT;
	}
	if (wHint != SWT.DEFAULT) width = wHint;
	if (hHint != SWT.DEFAULT) height = hHint;
	return new Point (width, height);
	}

	void createHandle () {
	int features = OS.kControlSupportsFocus;
	int [] outControl = new int [1];
	int window = OS.GetControlOwner (parent.handle);
	OS.CreateUserPaneControl (window, null, features, outControl);
	if (outControl [0] == 0) error (SWT.ERROR_NO_HANDLES);
	handle = outControl [0];
	}

	void drawBackground (int control) {
	drawBackground (control, background);
	}

	int kEventControlClick (int nextHandler, int theEvent, int userData) {
	int result = super.kEventControlClick (nextHandler, theEvent, userData);
	if (result == OS.noErr) return result;
	if (!isEnabled ()) return OS.noErr;
	return result;
	}

	int kEventControlSetCursor (int nextHandler, int theEvent, int userData) {
	int result = super.kEventControlSetCursor (nextHandler, theEvent, userData);
	if (result == OS.noErr) return result;
	display.setCursor (sizeCursor.handle);
	return OS.noErr;
	}

	int kEventMouseDown (int nextHandler, int theEvent, int userData) {
	int result = super.kEventMouseDown (nextHandler, theEvent, userData);
	if (result == OS.noErr) return result;

	Rect rect = new Rect ();
	OS.GetControlBounds (handle, rect);
	int startX = rect.left;
	int startY = rect.top;
	int width = rect.right - rect.left;
	int height = rect.bottom - rect.top;
	OS.GetControlBounds (parent.handle, rect);
	Event event = new Event ();
	event.x = startX -= rect.left;
	event.y = startY -= rect.top;
	event.width = width;
	event.height = height;
	sendEvent (SWT.Selection, event);
	if (isDisposed ()) return result;
	if (!event.doit) return result;

	int sizeof = org.eclipse.swt.internal.carbon.Point.sizeof;
	org.eclipse.swt.internal.carbon.Point pt = new org.eclipse.swt.internal.carbon.Point ();
	OS.GetEventParameter (theEvent, OS.kEventParamMouseLocation, OS.typeQDPoint, null, sizeof, null, pt);
	int window = OS.GetControlOwner (handle);
	OS.GetWindowBounds (window, (short) OS.kWindowContentRgn, rect);
	int offsetX = pt.h - rect.left;
	int offsetY = pt.v - rect.top;
	OS.GetControlBounds (handle, rect);
	offsetX -= rect.left;
	offsetY -= rect.top;

	int port = OS.GetWindowPort (window);
	int [] outModifiers = new int [1];
	short [] outResult = new short [1];
	org.eclipse.swt.internal.carbon.Point outPt = new org.eclipse.swt.internal.carbon.Point ();
	while (outResult [0] != OS.kMouseTrackingMouseUp) {
	OS.TrackMouseLocationWithOptions (port, 0, OS.kEventDurationForever, outPt, outModifiers, outResult);
	switch (outResult [0]) {
	case OS.kMouseTrackingMouseDown:
	case OS.kMouseTrackingMouseUp:
	case OS.kMouseTrackingMouseDragged: {
	OS.GetControlBounds (parent.handle, rect);
	int x = outPt.h - rect.left;
	int y = outPt.v - rect.top;
	int newX = startX, newY = startY;
	if ((style & SWT.VERTICAL) != 0) {
	int clientWidth = rect.right - rect.left;
	newX = Math.min (Math.max (0, x - offsetX), clientWidth - width);
	} else {
	int clientHeight = rect.bottom - rect.top;
	newY = Math.min (Math.max (0, y - offsetY), clientHeight - height);
	}
	event = new Event ();
	event.x = newX;
	event.y = newY;
	event.width = width;
	event.height = height;
	event.detail = 0; //outResult [0] == OS.kMouseTrackingMouseDragged ? SWT.DRAG : 0;
	sendEvent (SWT.Selection, event);
	if (isDisposed ()) return result;
	if (event.doit) {
	setBounds (newX, newY, width, height);
	Shell shell = parent.getShell ();
	shell.update (true);
	}
	break;
	}
	default:
	outResult [0] = OS.kMouseTrackingMouseUp;
	break;
	}
	}
	return result;
	}

	int kEventControlSetFocusPart (int nextHandler, int theEvent, int userData) {
	int result = super.kEventControlSetFocusPart (nextHandler, theEvent, userData);
	if (result == OS.noErr) return result;
	Point location = getLocation();
	lastX = location.x;
	lastY = location.y;
	return OS.noErr;
	}

	int kEventTextInputUnicodeForKeyEvent (int nextHandler, int theEvent, int userData) {
	int result = super.kEventTextInputUnicodeForKeyEvent (nextHandler, theEvent, userData);
	if (result == OS.noErr) return result;
	int [] keyboardEvent = new int [1];
	OS.GetEventParameter (theEvent, OS.kEventParamTextInputSendKeyboardEvent, OS.typeEventRef, null, keyboardEvent.length * 4, null, keyboardEvent);
	int [] keyCode = new int [1];
	OS.GetEventParameter (keyboardEvent [0], OS.kEventParamKeyCode, OS.typeUInt32, null, keyCode.length * 4, null, keyCode);
	switch (keyCode [0]) {
	case 126: /* Up arrow */
	case 123: /* Left arrow */
	case 125: /* Down arrow */
	case 124: /* Right arrow */ {
	int xChange = 0, yChange = 0;
	int stepSize = PAGE_INCREMENT;
	int [] modifiers = new int [1];
	OS.GetEventParameter (theEvent, OS.kEventParamKeyModifiers, OS.typeUInt32, null, 4, null, modifiers);
	if ((modifiers [0] & OS.controlKey) != 0) stepSize = INCREMENT;
	if ((style & SWT.VERTICAL) != 0) {
	if (keyCode [0] == 126 \|\| keyCode [0] == 125) break;
	xChange = keyCode [0] == 123 ? -stepSize : stepSize;
	} else {
	if (keyCode [0] == 123 \|\| keyCode [0] == 124) break;
	yChange = keyCode [0] == 126 ? -stepSize : stepSize;
	}

	Rectangle bounds = getBounds ();
	int width = bounds.width, height = bounds.height;
	Rectangle parentBounds = parent.getBounds ();
	int parentWidth = parentBounds.width;
	int parentHeight = parentBounds.height;
	int newX = lastX, newY = lastY;
	if ((style & SWT.VERTICAL) != 0) {
	newX = Math.min (Math.max (0, lastX + xChange - startX), parentWidth - width);
	} else {
	newY = Math.min (Math.max (0, lastY + yChange - startY), parentHeight - height);
	}
	if (newX == lastX && newY == lastY) return result;

	/* The event must be sent because its doit flag is used. */
	Event event = new Event ();
	event.x = newX; event.y = newY;
	event.width = width; event.height = height;
	sendEvent (SWT.Selection, event);

	/*
	* It is possible (but unlikely) that client code could have disposed
	* the widget in the selection event. If this happens end the processing
	* of this message by returning.
	*/
	if (isDisposed ()) break;
	if (event.doit) {
	lastX = event.x; lastY = event.y;
	/* Adjust the pointer position */
	int cursorX = newX; int cursorY = newY;
	if ((style & SWT.VERTICAL) != 0) {
	cursorY += height / 2;
	} else {
	cursorX += width / 2;
	}
	display.setCursorLocation (parent.toDisplay (cursorX, cursorY));
	}
	break;
	}
	}

	return result;
	}

	void releaseWidget () {
	super.releaseWidget ();
	if (sizeCursor != null) sizeCursor.dispose ();
	sizeCursor = null;
	}

	/**
	* Removes the listener from the collection of listeners who will
	* be notified when the control is selected.
	*
	* @param listener the listener which should be notified
	*
	* @exception IllegalArgumentException <ul>
	* <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
	* </ul>
	* @exception SWTException <ul>
	* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
	* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
	* </ul>
	*
	* @see SelectionListener
	* @see #addSelectionListener
	*/
	public void removeSelectionListener(SelectionListener listener) {
	checkWidget();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (eventTable == null) return;
	eventTable.unhook(SWT.Selection, listener);
	eventTable.unhook(SWT.DefaultSelection,listener);
	}

	int traversalCode (int key, int theEvent) {
	return 0;
	}

	}