org.eclipse.swt.widgets.Tracker.java Source code

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/*******************************************************************************
 * Copyright (c) 2000, 2009 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.swt.widgets;

import org.eclipse.swt.internal.wpf.*;
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>
 *
 * @see <a href="http://www.eclipse.org/swt/snippets/#tracker">Tracker snippets</a>
 * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
 * @noextend This class is not intended to be subclassed by clients.
 */
public class Tracker extends Widget {
    Composite parent;
    boolean cancelled, stippled;
    Rectangle[] rectangles, proportions;
    Rectangle bounds;
    Cursor clientCursor;
    int resizeCursor, cursorOrientation = SWT.NONE;
    int oldX, oldY;
    int canvasHandle;
    int frame;

    /*
    * 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
     * @see SWT#RESIZE
     */
    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;
        reskinWidget();
    }

    /**
     * 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);
    }

    /**
     * Adds the listener to the collection of listeners who will
     * be notified when keys are pressed and released on the system keyboard, by sending
     * it one of the messages defined in the <code>KeyListener</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 KeyListener
     * @see #removeKeyListener
     */
    public void addKeyListener(KeyListener listener) {
        checkWidget();
        if (listener == null)
            error(SWT.ERROR_NULL_ARGUMENT);
        TypedListener typedListener = new TypedListener(listener);
        addListener(SWT.KeyUp, typedListener);
        addListener(SWT.KeyDown, typedListener);
    }

    Point adjustMoveCursor() {
        if (bounds == null)
            return null;
        int newX = bounds.x + bounds.width / 2;
        int newY = bounds.y;
        Point point = display.map(parent, null, newX, newY);
        display.setCursorLocation(point);
        return point;
    }

    Point adjustResizeCursor() {
        if (bounds == null)
            return null;
        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 point = display.map(parent, null, newX, newY);
        display.setCursorLocation(point);

        /*
        * If the client has not provided a custom cursor then determine
        * the appropriate resize cursor.
        */
        if (clientCursor == null) {
            int newCursor = 0;
            switch (cursorOrientation) {
            case SWT.UP:
                newCursor = OS.Cursors_SizeNS();
                break;
            case SWT.DOWN:
                newCursor = OS.Cursors_SizeNS();
                break;
            case SWT.LEFT:
                newCursor = OS.Cursors_SizeWE();
                break;
            case SWT.RIGHT:
                newCursor = OS.Cursors_SizeWE();
                break;
            case SWT.LEFT | SWT.UP:
                newCursor = OS.Cursors_SizeNWSE();
                break;
            case SWT.RIGHT | SWT.DOWN:
                newCursor = OS.Cursors_SizeNWSE();
                break;
            case SWT.LEFT | SWT.DOWN:
                newCursor = OS.Cursors_SizeNESW();
                break;
            case SWT.RIGHT | SWT.UP:
                newCursor = OS.Cursors_SizeNESW();
                break;
            default:
                newCursor = OS.Cursors_SizeAll();
                break;
            }
            OS.FrameworkElement_Cursor(canvasHandle, newCursor);
            if (resizeCursor != 0) {
                OS.GCHandle_Free(resizeCursor);
            }
            resizeCursor = newCursor;
        }
        return point;
    }

    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();
        if (frame != 0)
            OS.DispatcherFrame_Continue(frame, false);
    }

    Rectangle computeBounds() {
        if (rectangles.length == 0)
            return null;
        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();
        if (bounds != null) {
            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 bounds = this.bounds;
        if (bounds == null)
            return;
        int children = OS.Panel_Children(canvasHandle);
        OS.UIElementCollection_Clear(children);
        if (parent != null) {
            Rectangle rect = parent.getClientArea();
            rect.intersect(bounds);
            bounds = rect;
            Point pt = display.map(parent, null, bounds.x, bounds.y);
            OS.Popup_HorizontalOffset(handle, pt.x);
            OS.Popup_VerticalOffset(handle, pt.y);
        } else {
            OS.Popup_HorizontalOffset(handle, bounds.x);
            OS.Popup_VerticalOffset(handle, bounds.y);
        }
        OS.FrameworkElement_Width(handle, bounds.width);
        OS.FrameworkElement_Height(handle, bounds.height);
        int stroke, brush;
        if (stippled) {
            stroke = 3;
            int pixelFormat = OS.PixelFormats_BlackWhite();
            byte[] buffer = { -86, 0, 85, 0, -86, 0, 85, 0, -86, 0, 85, 0, -86, 0, 85, 0 };
            int image = OS.BitmapSource_Create(8, 8, 96, 96, pixelFormat, 0, buffer, buffer.length, 2);
            OS.GCHandle_Free(pixelFormat);
            brush = OS.gcnew_ImageBrush(image);
            OS.TileBrush_TileMode(brush, OS.TileMode_Tile);
            OS.TileBrush_Stretch(brush, OS.Stretch_Fill);
            OS.TileBrush_ViewportUnits(brush, OS.BrushMappingMode_Absolute);
            int rect = OS.gcnew_Rect(0, 0, OS.BitmapSource_PixelWidth(image), OS.BitmapSource_PixelHeight(image));
            OS.TileBrush_Viewport(brush, rect);
            OS.GCHandle_Free(rect);
            OS.GCHandle_Free(image);
        } else {
            stroke = 1;
            brush = OS.Brushes_Black();
        }
        for (int i = 0; i < rectangles.length; i++) {
            int child = OS.gcnew_Rectangle();
            OS.UIElementCollection_Add(children, child);
            OS.Shape_StrokeThickness(child, stroke);
            OS.Shape_Stroke(child, brush);
            Rectangle rect = rectangles[i];
            OS.Canvas_SetLeft(child, rect.x - bounds.x);
            OS.Canvas_SetTop(child, rect.y - bounds.y);
            OS.FrameworkElement_Width(child, rect.width);
            OS.FrameworkElement_Height(child, rect.height);
            OS.GCHandle_Free(child);
        }
        OS.GCHandle_Free(brush);
        OS.GCHandle_Free(children);
    }

    /**
     * Returns the bounds that are being drawn, expressed relative to the parent
     * widget.  If the parent is a <code>Display</code> then these are screen
     * coordinates.
     *
     * @return the bounds of the Rectangles being drawn
     * 
     * @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 Rectangle[] getRectangles() {
        checkWidget();
        int length = 0;
        if (rectangles != null)
            length = rectangles.length;
        Rectangle[] result = new Rectangle[length];
        for (int i = 0; i < length; i++) {
            Rectangle current = rectangles[i];
            result[i] = new Rectangle(current.x, current.y, current.width, current.height);
        }
        return result;
    }

    /**
     * Returns <code>true</code> if the rectangles are drawn with a stippled line, <code>false</code> otherwise.
     *
     * @return the stippled effect of the rectangles
     *
     * @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 boolean getStippled() {
        checkWidget();
        return stippled;
    }

    void HandleKeyUp(int sender, int e) {
        if (handle == 0)
            return;
        if (!sendKeyEvent(SWT.KeyUp, e, false))
            return;
    }

    void HandleKeyDown(int sender, int e) {
        if (handle == 0)
            return;
        if (!sendKeyEvent(SWT.KeyDown, e, false))
            return;

        boolean ctrlDown = (OS.Keyboard_Modifiers() & OS.ModifierKeys_Control) != 0;
        int stepSize = ctrlDown ? STEPSIZE_SMALL : STEPSIZE_LARGE;
        int key = OS.KeyEventArgs_Key(e);
        int xChange = 0, yChange = 0;
        switch (key) {
        case OS.Key_System:
        case OS.Key_Escape:
            cancelled = true;
            if (frame != 0)
                OS.DispatcherFrame_Continue(frame, false);
            break;
        case OS.Key_Return:
            if (frame != 0)
                OS.DispatcherFrame_Continue(frame, false);
            break;
        case OS.Key_Left:
            xChange = -stepSize;
            break;
        case OS.Key_Right:
            xChange = stepSize;
            break;
        case OS.Key_Up:
            yChange = -stepSize;
            break;
        case OS.Key_Down:
            yChange = stepSize;
            break;
        }
        if (xChange != 0 || yChange != 0) {
            Event event = new Event();
            event.x = oldX + xChange;
            event.y = oldY + yChange;
            Point cursorPos;
            if ((style & SWT.RESIZE) != 0) {
                resizeRectangles(xChange, yChange);
                sendEvent(SWT.Resize, event);
                if (isDisposed()) {
                    cancelled = true;
                    if (frame != 0)
                        OS.DispatcherFrame_Continue(frame, false);
                    return;
                }
                drawRectangles();
                cursorPos = adjustResizeCursor();
            } else {
                moveRectangles(xChange, yChange);
                sendEvent(SWT.Move, event);
                if (isDisposed()) {
                    cancelled = true;
                    if (frame != 0)
                        OS.DispatcherFrame_Continue(frame, false);
                    return;
                }
                drawRectangles();
                cursorPos = adjustMoveCursor();
            }
            oldX = cursorPos.x;
            oldY = cursorPos.y;
        }
    }

    void HandleMouseUp(int sender, int e) {
        if (handle == 0)
            return;
        if (!sendMouseEvent(SWT.MouseUp, e, false))
            return;
        if (frame != 0)
            OS.DispatcherFrame_Continue(frame, false);
    }

    void HandleMouseDown(int sender, int e) {
        if (handle == 0)
            return;
        if (!sendMouseEvent(SWT.MouseDown, e, false))
            return;
        if (frame != 0)
            OS.DispatcherFrame_Continue(frame, false);
    }

    void HandleMouseMove(int sender, int e) {
        if (handle == 0)
            return;
        if (!sendMouseEvent(SWT.MouseMove, e, false))
            return;
        int pointCanvas = OS.MouseEventArgs_GetPosition(e, canvasHandle);
        int point = OS.Visual_PointToScreen(canvasHandle, pointCanvas);
        int newX = (int) OS.Point_X(point);
        int newY = (int) OS.Point_Y(point);
        OS.GCHandle_Free(pointCanvas);
        OS.GCHandle_Free(point);
        if (newX != oldX || newY != oldY) {
            Event event = new Event();
            event.x = newX;
            event.y = newY;
            if ((style & SWT.RESIZE) != 0) {
                resizeRectangles(newX - oldX, newY - oldY);
                sendEvent(SWT.Resize, event);
                if (isDisposed()) {
                    cancelled = true;
                    if (frame != 0)
                        OS.DispatcherFrame_Continue(frame, false);
                }
                drawRectangles();
                Point cursorPos = adjustResizeCursor();
                if (cursorPos != null) {
                    newX = cursorPos.x;
                    newY = cursorPos.y;
                }
            } else {
                moveRectangles(newX - oldX, newY - oldY);
                sendEvent(SWT.Move, event);
                if (isDisposed()) {
                    cancelled = true;
                    if (frame != 0)
                        OS.DispatcherFrame_Continue(frame, false);
                }
                drawRectangles();
            }
            oldX = newX;
            oldY = newY;
        }
    }

    void moveRectangles(int xChange, int yChange) {
        if (bounds == null)
            return;
        if (xChange < 0 && ((style & SWT.LEFT) == 0))
            xChange = 0;
        if (xChange > 0 && ((style & SWT.RIGHT) == 0))
            xChange = 0;
        if (yChange < 0 && ((style & SWT.UP) == 0))
            yChange = 0;
        if (yChange > 0 && ((style & SWT.DOWN) == 0))
            yChange = 0;
        if (xChange == 0 && yChange == 0)
            return;
        bounds.x += xChange;
        bounds.y += yChange;
        for (int i = 0; i < rectangles.length; i++) {
            rectangles[i].x += xChange;
            rectangles[i].y += yChange;
        }
    }

    /**
     * Displays the Tracker rectangles for manipulation by the user.  Returns when
     * the user has either finished manipulating the rectangles or has cancelled the
     * Tracker.
     * 
     * @return <code>true</code> if the user did not cancel the Tracker, <code>false</code> otherwise
     * 
     * @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 boolean open() {
        checkWidget();
        if (rectangles == null)
            return false;
        if (rectangles.length == 0)
            return false;
        cancelled = false;

        /*
        * If exactly one of UP/DOWN is specified as a style then set the cursor
        * orientation accordingly (the same is done for LEFT/RIGHT styles below).
        */
        int vStyle = style & (SWT.UP | SWT.DOWN);
        if (vStyle == SWT.UP || vStyle == SWT.DOWN) {
            cursorOrientation |= vStyle;
        }
        int hStyle = style & (SWT.LEFT | SWT.RIGHT);
        if (hStyle == SWT.LEFT || hStyle == SWT.RIGHT) {
            cursorOrientation |= hStyle;
        }

        jniRef = OS.NewGlobalRef(this);
        if (jniRef == 0)
            error(SWT.ERROR_NO_HANDLES);
        handle = OS.gcnew_Popup();
        if (handle == 0)
            error(SWT.ERROR_NO_HANDLES);
        OS.Popup_AllowsTransparency(handle, true);

        canvasHandle = OS.gcnew_Canvas();
        if (canvasHandle == 0)
            error(SWT.ERROR_NO_HANDLES);
        OS.Popup_Child(handle, canvasHandle);
        OS.UIElement_IsHitTestVisible(canvasHandle, false);
        OS.FrameworkElement_FocusVisualStyle(canvasHandle, 0);
        if (clientCursor != null) {
            OS.FrameworkElement_Cursor(canvasHandle, clientCursor.handle);
        }

        drawRectangles();

        OS.Popup_IsOpen(handle, true);
        OS.UIElement_Focusable(canvasHandle, true);
        OS.UIElement_Focus(canvasHandle);
        OS.UIElement_CaptureMouse(canvasHandle);

        boolean mouseDown = OS.Mouse_LeftButton() == OS.MouseButtonState_Pressed;
        Point cursorPos;
        if (mouseDown) {
            int pointCanvas = OS.Mouse_GetPosition(canvasHandle);
            int point = OS.Visual_PointToScreen(canvasHandle, pointCanvas);
            cursorPos = new Point((int) OS.Point_X(point), (int) OS.Point_Y(point));
            OS.GCHandle_Free(pointCanvas);
            OS.GCHandle_Free(point);
        } else {
            if ((style & SWT.RESIZE) != 0) {
                cursorPos = adjustResizeCursor();
            } else {
                cursorPos = adjustMoveCursor();
            }
        }
        oldX = cursorPos.x;
        oldY = cursorPos.y;

        int handler = OS.gcnew_KeyEventHandler(jniRef, "HandleKeyDown");
        OS.UIElement_KeyDown(canvasHandle, handler);
        OS.GCHandle_Free(handler);
        handler = OS.gcnew_KeyEventHandler(jniRef, "HandleKeyUp");
        OS.UIElement_KeyUp(canvasHandle, handler);
        OS.GCHandle_Free(handler);
        handler = OS.gcnew_MouseEventHandler(jniRef, "HandleMouseMove");
        OS.UIElement_MouseMove(canvasHandle, handler);
        OS.GCHandle_Free(handler);
        handler = OS.gcnew_MouseButtonEventHandler(jniRef, "HandleMouseUp");
        OS.UIElement_MouseUp(canvasHandle, handler);
        OS.GCHandle_Free(handler);
        handler = OS.gcnew_MouseButtonEventHandler(jniRef, "HandleMouseDown");
        OS.UIElement_MouseDown(canvasHandle, handler);
        OS.GCHandle_Free(handler);

        /* Tracker behaves like a Dialog with its own OS event loop. */
        frame = OS.gcnew_DispatcherFrame();
        OS.Dispatcher_PushFrame(frame);

        if (resizeCursor != 0) {
            OS.GCHandle_Free(resizeCursor);
            resizeCursor = 0;
        }
        OS.UIElement_ReleaseMouseCapture(canvasHandle);
        OS.Popup_IsOpen(handle, false);
        OS.GCHandle_Free(canvasHandle);
        OS.GCHandle_Free(handle);
        if (frame != 0)
            OS.GCHandle_Free(frame);
        OS.DeleteGlobalRef(jniRef);
        jniRef = handle = canvasHandle = frame = 0;

        return !cancelled;
    }

    /**
     * Removes the listener from the collection of listeners who will
     * be notified when the control is moved or resized.
     *
     * @param listener the listener which should no longer 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 #addControlListener
     */
    public void removeControlListener(ControlListener listener) {
        checkWidget();
        if (listener == null)
            error(SWT.ERROR_NULL_ARGUMENT);
        if (eventTable == null)
            return;
        eventTable.unhook(SWT.Resize, listener);
        eventTable.unhook(SWT.Move, listener);
    }

    /**
     * Removes the listener from the collection of listeners who will
     * be notified when keys are pressed and released on the system keyboard.
     *
     * @param listener the listener which should no longer 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 KeyListener
     * @see #addKeyListener
     */
    public void removeKeyListener(KeyListener listener) {
        checkWidget();
        if (listener == null)
            error(SWT.ERROR_NULL_ARGUMENT);
        if (eventTable == null)
            return;
        eventTable.unhook(SWT.KeyUp, listener);
        eventTable.unhook(SWT.KeyDown, listener);
    }

    void resizeRectangles(int xChange, int yChange) {
        if (bounds == null)
            return;
        /*
        * If the cursor orientation has not been set in the orientation of
        * this change then try to set it here.
        */
        if (xChange < 0 && ((style & SWT.LEFT) != 0) && ((cursorOrientation & SWT.RIGHT) == 0)) {
            cursorOrientation |= SWT.LEFT;
        }
        if (xChange > 0 && ((style & SWT.RIGHT) != 0) && ((cursorOrientation & SWT.LEFT) == 0)) {
            cursorOrientation |= SWT.RIGHT;
        }
        if (yChange < 0 && ((style & SWT.UP) != 0) && ((cursorOrientation & SWT.DOWN) == 0)) {
            cursorOrientation |= SWT.UP;
        }
        if (yChange > 0 && ((style & SWT.DOWN) != 0) && ((cursorOrientation & SWT.UP) == 0)) {
            cursorOrientation |= SWT.DOWN;
        }

        /*
         * If the bounds will flip about the x or y axis then apply the adjustment
         * up to the axis (ie.- where bounds width/height becomes 0), change the
         * cursor's orientation accordingly, and flip each Rectangle's origin (only
         * necessary for > 1 Rectangles) 
         */
        if ((cursorOrientation & SWT.LEFT) != 0) {
            if (xChange > bounds.width) {
                if ((style & SWT.RIGHT) == 0)
                    return;
                cursorOrientation |= SWT.RIGHT;
                cursorOrientation &= ~SWT.LEFT;
                bounds.x += bounds.width;
                xChange -= bounds.width;
                bounds.width = 0;
                if (proportions.length > 1) {
                    for (int i = 0; i < proportions.length; i++) {
                        Rectangle proportion = proportions[i];
                        proportion.x = 100 - proportion.x - proportion.width;
                    }
                }
            }
        } else if ((cursorOrientation & SWT.RIGHT) != 0) {
            if (bounds.width < -xChange) {
                if ((style & SWT.LEFT) == 0)
                    return;
                cursorOrientation |= SWT.LEFT;
                cursorOrientation &= ~SWT.RIGHT;
                xChange += bounds.width;
                bounds.width = 0;
                if (proportions.length > 1) {
                    for (int i = 0; i < proportions.length; i++) {
                        Rectangle proportion = proportions[i];
                        proportion.x = 100 - proportion.x - proportion.width;
                    }
                }
            }
        }
        if ((cursorOrientation & SWT.UP) != 0) {
            if (yChange > bounds.height) {
                if ((style & SWT.DOWN) == 0)
                    return;
                cursorOrientation |= SWT.DOWN;
                cursorOrientation &= ~SWT.UP;
                bounds.y += bounds.height;
                yChange -= bounds.height;
                bounds.height = 0;
                if (proportions.length > 1) {
                    for (int i = 0; i < proportions.length; i++) {
                        Rectangle proportion = proportions[i];
                        proportion.y = 100 - proportion.y - proportion.height;
                    }
                }
            }
        } else if ((cursorOrientation & SWT.DOWN) != 0) {
            if (bounds.height < -yChange) {
                if ((style & SWT.UP) == 0)
                    return;
                cursorOrientation |= SWT.UP;
                cursorOrientation &= ~SWT.DOWN;
                yChange += bounds.height;
                bounds.height = 0;
                if (proportions.length > 1) {
                    for (int i = 0; i < proportions.length; i++) {
                        Rectangle proportion = proportions[i];
                        proportion.y = 100 - proportion.y - proportion.height;
                    }
                }
            }
        }

        // apply the bounds adjustment
        if ((cursorOrientation & SWT.LEFT) != 0) {
            bounds.x += xChange;
            bounds.width -= xChange;
        } else if ((cursorOrientation & SWT.RIGHT) != 0) {
            bounds.width += xChange;
        }
        if ((cursorOrientation & SWT.UP) != 0) {
            bounds.y += yChange;
            bounds.height -= yChange;
        } else if ((cursorOrientation & SWT.DOWN) != 0) {
            bounds.height += yChange;
        }

        Rectangle[] newRects = new Rectangle[rectangles.length];
        for (int i = 0; i < rectangles.length; i++) {
            Rectangle proportion = proportions[i];
            newRects[i] = new Rectangle(proportion.x * bounds.width / 100 + bounds.x,
                    proportion.y * bounds.height / 100 + bounds.y, proportion.width * bounds.width / 100,
                    proportion.height * bounds.height / 100);
        }
        rectangles = newRects;
    }

    /**
     * Sets the <code>Cursor</code> of the Tracker.  If this cursor is <code>null</code>
     * then the cursor reverts to the default.
     *
     * @param newCursor the new <code>Cursor</code> to display
     * 
     * @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 setCursor(Cursor newCursor) {
        checkWidget();
        clientCursor = newCursor;
        if (canvasHandle != 0) {
            OS.FrameworkElement_Cursor(canvasHandle, clientCursor != null ? clientCursor.handle : 0);
        }
    }

    /**
     * Specifies the rectangles that should be drawn, expressed relative to the parent
     * widget.  If the parent is a Display then these are screen coordinates.
     *
     * @param rectangles the bounds of the rectangles to be drawn
     *
     * @exception IllegalArgumentException <ul>
     *    <li>ERROR_NULL_ARGUMENT - if the set of rectangles is null or contains a null rectangle</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>
     */
    public void setRectangles(Rectangle[] rectangles) {
        checkWidget();
        if (rectangles == null)
            error(SWT.ERROR_NULL_ARGUMENT);
        int length = rectangles.length;
        this.rectangles = new Rectangle[length];
        for (int i = 0; i < length; i++) {
            Rectangle current = rectangles[i];
            if (current == null)
                error(SWT.ERROR_NULL_ARGUMENT);
            this.rectangles[i] = new Rectangle(current.x, current.y, current.width, current.height);
        }
        proportions = computeProportions(rectangles);
    }

    /**
     * Changes the appearance of the line used to draw the rectangles.
     *
     * @param stippled <code>true</code> if rectangle should appear stippled
     *
     * @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 setStippled(boolean stippled) {
        checkWidget();
        this.stippled = stippled;
        if (handle != 0) {
            //TODO CHANGE RECT BRUSH
        }
    }

}