/******************************************************************************* * Copyright (c) 2000, 2004 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.*;import org.eclipse.swt.internal.win32.*;import org.eclipse.swt.graphics.*;import org.eclipse.swt.*;import org.eclipse.swt.events.*;/** *  Instances of this class implement rubber banding rectangles that are *  drawn onto a parent <code>Composite</code> or <code>Display</code>. *  These rectangles can be specified to respond to mouse and key events *  by either moving or resizing themselves accordingly.  Trackers are *  typically used to represent window geometries in a lightweight manner. *   * <dl> * <dt><b>Styles:</b></dt> * <dd>LEFT, RIGHT, UP, DOWN, RESIZE</dd> * <dt><b>Events:</b></dt> * <dd>Move, Resize</dd> * </dl> * <p> * Note: Rectangle move behavior is assumed unless RESIZE is specified. * </p><p> * IMPORTANT: This class is <em>not</em> intended to be subclassed. * </p> */public class Tracker extends Widget {	Control parent;	boolean tracking, stippled;	Rectangle [] rectangles, proportions;	Rectangle bounds;	int resizeCursor, clientCursor, cursorOrientation = SWT.NONE;	boolean inEvent = false;	/*	* The following values mirror step sizes on Windows	*/	final static int STEPSIZE_SMALL = 1;	final static int STEPSIZE_LARGE = 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 widget which will be the parent of the new instance (cannot be null) * @param style the style of widget 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#LEFT * @see SWT#RIGHT * @see SWT#UP * @see SWT#DOWN * @see SWT#RESIZE * @see Widget#checkSubclass * @see Widget#getStyle */public Tracker (Composite parent, int style) {	super (parent, checkStyle (style));	this.parent = parent;}/** * Constructs a new instance of this class given the display * to create it on 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><p> * Note: Currently, null can be passed in for the display argument. * This has the effect of creating the tracker on the currently active * display if there is one. If there is no current display, the  * tracker is created on a "default" display. <b>Passing in null as * the display argument is not considered to be good coding style, * and may not be supported in a future release of SWT.</b> * </p> * * @param display the display to create the tracker on * @param style the style of control to construct * * @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#LEFT * @see SWT#RIGHT * @see SWT#UP * @see SWT#DOWN */public Tracker (Display display, int style) {	if (display == null) display = Display.getCurrent ();	if (display == null) display = Display.getDefault ();	if (!display.isValidThread ()) {		error (SWT.ERROR_THREAD_INVALID_ACCESS);	}	this.style = checkStyle (style);	this.display = display;}/** * Adds the listener to the collection of listeners who will * be notified when the control is moved or resized, by sending * it one of the messages defined in the <code>ControlListener</code> * interface. * * @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 ControlListener * @see #removeControlListener */public void addControlListener (ControlListener listener) {	checkWidget ();	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);	TypedListener typedListener = new TypedListener (listener);	addListener (SWT.Resize, typedListener);	addListener (SWT.Move, typedListener);}Point adjustMoveCursor () {	int newX = bounds.x + bounds.width / 2;	int newY = bounds.y;	POINT pt = new POINT ();	pt.x = newX;  pt.y = newY;	/*	 * Convert to screen coordinates iff needed 	 */	if (parent != null) {		OS.ClientToScreen (parent.handle, pt);	}	OS.SetCursorPos (pt.x, pt.y);	return new Point (pt.x, pt.y);}Point adjustResizeCursor () {	int newX, newY;	if ((cursorOrientation & SWT.LEFT) != 0) {		newX = bounds.x;	} else if ((cursorOrientation & SWT.RIGHT) != 0) {		newX = bounds.x + bounds.width;	} else {		newX = bounds.x + bounds.width / 2;	}	if ((cursorOrientation & SWT.UP) != 0) {		newY = bounds.y;	} else if ((cursorOrientation & SWT.DOWN) != 0) {		newY = bounds.y + bounds.height;	} else {		newY = bounds.y + bounds.height / 2;	}	POINT pt = new POINT ();	pt.x = newX;  pt.y = newY;	/*	 * Convert to screen coordinates iff needed	 */	if (parent != null) {		OS.ClientToScreen (parent.handle, pt);	}	OS.SetCursorPos (pt.x, pt.y);	/*	* If the client has not provided a custom cursor then determine	* the appropriate resize cursor.	*/	if (clientCursor == 0) {		int newCursor = 0;		switch (cursorOrientation) {			case SWT.UP:				newCursor = OS.LoadCursor (0, OS.IDC_SIZENS);				break;			case SWT.DOWN:				newCursor = OS.LoadCursor (0, OS.IDC_SIZENS);				break;			case SWT.LEFT:				newCursor = OS.LoadCursor (0, OS.IDC_SIZEWE);				break;			case SWT.RIGHT:				newCursor = OS.LoadCursor (0, OS.IDC_SIZEWE);				break;			case SWT.LEFT | SWT.UP:				newCursor = OS.LoadCursor (0, OS.IDC_SIZENWSE);				break;			case SWT.RIGHT | SWT.DOWN:				newCursor = OS.LoadCursor (0, OS.IDC_SIZENWSE);				break;			case SWT.LEFT | SWT.DOWN:				newCursor = OS.LoadCursor (0, OS.IDC_SIZENESW);				break;			case SWT.RIGHT | SWT.UP:				newCursor = OS.LoadCursor (0, OS.IDC_SIZENESW);				break;			default:				newCursor = OS.LoadCursor (0, OS.IDC_SIZEALL);				break;		}		OS.SetCursor (newCursor);		if (resizeCursor != 0) {			OS.DestroyCursor (resizeCursor);		}		resizeCursor = newCursor;	}			return new Point (pt.x, pt.y);}static int checkStyle (int style) {	if ((style & (SWT.LEFT | SWT.RIGHT | SWT.UP | SWT.DOWN)) == 0) {		style |= SWT.LEFT | SWT.RIGHT | SWT.UP | SWT.DOWN;	}	return style;}/** * Stops displaying the tracker rectangles.  Note that this is not considered * to be a cancelation by the user. * * @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> */public void close () {	checkWidget ();	tracking = false;}Rectangle computeBounds () {	int xMin = rectangles [0].x;	int yMin = rectangles [0].y;	int xMax = rectangles [0].x + rectangles [0].width;	int yMax = rectangles [0].y + rectangles [0].height;		for (int i = 1; i < rectangles.length; i++) {		if (rectangles [i].x < xMin) xMin = rectangles [i].x;		if (rectangles [i].y < yMin) yMin = rectangles [i].y;		int rectRight = rectangles [i].x + rectangles [i].width;		if (rectRight > xMax) xMax = rectRight;				int rectBottom = rectangles [i].y + rectangles [i].height;		if (rectBottom > yMax) yMax = rectBottom;	}		return new Rectangle (xMin, yMin, xMax - xMin, yMax - yMin);}Rectangle [] computeProportions (Rectangle [] rects) {	Rectangle [] result = new Rectangle [rects.length];	bounds = computeBounds ();	for (int i = 0; i < rects.length; i++) {		int x = 0, y = 0, width = 0, height = 0;		if (bounds.width != 0) {			x = (rects [i].x - bounds.x) * 100 / bounds.width;			width = rects [i].width * 100 / bounds.width;		} else {			width = 100;		}		if (bounds.height != 0) {			y = (rects [i].y - bounds.y) * 100 / bounds.height;			height = rects [i].height * 100 / bounds.height;		} else {			height = 100;		}		result [i] = new Rectangle (x, y, width, height);				}	return result;}/** * Draw the rectangles displayed by the tracker. */void drawRectangles (Rectangle [] rects, boolean stippled) {	if (parent != null) {		if (parent.isDisposed ()) return;		Shell shell = parent.getShell ();		shell.update (true);	} else {		display.update ();	}	int bandWidth = 1;	int hwndTrack = OS.GetDesktopWindow ();	if (parent != null) hwndTrack = parent.handle;	int hDC = OS.GetDCEx (hwndTrack, 0, OS.DCX_CACHE);	int hBitmap = 0, hBrush = 0, oldBrush = 0;