bundles/org.eclipse.swt/Eclipse SWT/motif/org/eclipse/swt/widgets/Scrollable.java - platform/eclipse.platform.swt - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2008 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.motif.*;
 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;

 /**
  * This class is the abstract superclass of all classes which
  * represent controls that have standard scroll bars.
  * <dl>
  * <dt><b>Styles:</b></dt>
  * <dd>H_SCROLL, V_SCROLL</dd>
  * <dt><b>Events:</b>
  * <dd>(none)</dd>
  * </dl>
  * <p>
  * IMPORTANT: This class is intended to be subclassed <em>only</em>
  * within the SWT implementation.
  * </p>
  *
  * @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 abstract class Scrollable extends Control {
 	int scrolledHandle, formHandle;
 	ScrollBar horizontalBar, verticalBar;
 Scrollable () {
 	/* Do nothing */
 }
 /**
  * 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#H_SCROLL
  * @see SWT#V_SCROLL
  * @see Widget#checkSubclass
  * @see Widget#getStyle
  */
 public Scrollable (Composite parent, int style) {
 	super (parent, style);
 }
 /**
  * Given a desired <em>client area</em> for the receiver
  * (as described by the arguments), returns the bounding
  * rectangle which would be required to produce that client
  * area.
  * <p>
  * In other words, it returns a rectangle such that, if the
  * receiver's bounds were set to that rectangle, the area
  * of the receiver which is capable of displaying data
  * (that is, not covered by the "trimmings") would be the
  * rectangle described by the arguments (relative to the
  * receiver's parent).
  * </p>
  *
  * @param x the desired x coordinate of the client area
  * @param y the desired y coordinate of the client area
  * @param width the desired width of the client area
  * @param height the desired height of the client area
  * @return the required bounds to produce the given client area
  *
  * @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 #getClientArea
  */
 public Rectangle computeTrim (int x, int y, int width, int height) {
 	checkWidget();
 	int border = getBorderWidth ();
 	int trimX = x - border, trimY = y - border;
 	int trimWidth = width + (border * 2), trimHeight = height + (border * 2);
 	if (horizontalBar != null) {
 		trimY -= display.scrolledInsetY;
 		trimHeight += display.scrolledInsetY + display.scrolledMarginY;
 		if (verticalBar == null) {
 			trimX -= display.scrolledInsetX;
 			trimWidth += display.scrolledInsetX * 2;
 			trimHeight -= display.scrolledInsetY * 2;
 		}
 	}
 	if (verticalBar != null) {
 		trimX -= display.scrolledInsetX;
 		trimWidth += display.scrolledInsetX + display.scrolledMarginX;
 		if (horizontalBar == null) {
 			trimY -= display.scrolledInsetY;
 			trimHeight += display.scrolledInsetY * 2;
 			trimWidth -= display.scrolledInsetX * 2;
 		}
 	}
 	return new Rectangle (trimX, trimY, trimWidth, trimHeight);
 }
 ScrollBar createScrollBar (int type) {
 	return new ScrollBar (this, type);
 }
 ScrollBar createStandardBar (int style) {
 	if (scrolledHandle == 0) return null;
 	ScrollBar bar = new ScrollBar ();
 	bar.parent = this;
 	bar.style = style;
 	bar.display = display;
 	int [] argList = {OS.XmNhorizontalScrollBar, 0, OS.XmNverticalScrollBar, 0};
 	OS.XtGetValues (scrolledHandle, argList, argList.length / 2);
 	if (style == SWT.H_SCROLL) bar.handle = argList [1];
 	if (style == SWT.V_SCROLL) bar.handle = argList [3];
 	bar.hookEvents ();
 	bar.register ();
 	return bar;
 }
 void createWidget (int index) {
 	super.createWidget (index);
 	if ((style & SWT.H_SCROLL) != 0) horizontalBar = createScrollBar (SWT.H_SCROLL);
 	if ((style & SWT.V_SCROLL) != 0) verticalBar = createScrollBar (SWT.V_SCROLL);
 }
 void destroyScrollBar (ScrollBar bar) {
 	setScrollBarVisible (bar, false);
 	if ((state & CANVAS) != 0) bar.destroyHandle ();
 }
 void deregister () {
 	super.deregister ();
 	if (formHandle != 0) display.removeWidget (formHandle);
 	if (scrolledHandle != 0) display.removeWidget (scrolledHandle);
 }
 void enableWidget (boolean enabled) {
 	super.enableWidget (enabled);
 	if (formHandle != 0) enableHandle (enabled, formHandle);
 	if (scrolledHandle != 0) enableHandle (enabled, scrolledHandle);
 }
 /**
  * Returns a rectangle which describes the area of the
  * receiver which is capable of displaying data (that is,
  * not covered by the "trimmings").
  *
  * @return the client area
  *
  * @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 #computeTrim
  */
 public Rectangle getClientArea () {
 	checkWidget();
 	int [] argList = {OS.XmNwidth, 0, OS.XmNheight, 0};
 	OS.XtGetValues (handle, argList, argList.length / 2);
 	return new Rectangle (0, 0, argList [1], argList [3]);
 }
 /**
  * Returns the receiver's horizontal scroll bar if it has
  * one, and null if it does not.
  *
  * @return the horizontal scroll bar (or null)
  *
  * @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 ScrollBar getHorizontalBar () {
 	checkWidget();
 	return horizontalBar;
 }
 /**
  * Returns the receiver's vertical scroll bar if it has
  * one, and null if it does not.
  *
  * @return the vertical scroll bar (or null)
  *
  * @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 ScrollBar getVerticalBar () {
 	checkWidget();
 	return verticalBar;
 }
 void manageChildren () {
 	if (scrolledHandle != 0) {
 		OS.XtSetMappedWhenManaged (scrolledHandle, false);
 		OS.XtManageChild (scrolledHandle);
 	}
 	if (formHandle != 0) {
 		OS.XtSetMappedWhenManaged (formHandle, false);
 		OS.XtManageChild (formHandle);
 	}
 	super.manageChildren ();
 	if (formHandle != 0) {
 		int [] argList = {OS.XmNborderWidth, 0};
 		OS.XtGetValues (formHandle, argList, argList.length / 2);
 		OS.XtResizeWidget (formHandle, 1, 1, argList [1]);
 		OS.XtSetMappedWhenManaged (formHandle, true);
 	}
 	if (scrolledHandle != 0) {
 		int [] argList = {OS.XmNborderWidth, 0};
 		OS.XtGetValues (scrolledHandle, argList, argList.length / 2);
 		OS.XtResizeWidget (scrolledHandle, 1, 1, argList [1]);
 		OS.XtSetMappedWhenManaged (scrolledHandle, true);
 	}
 }
 void propagateWidget (boolean enabled) {
 	super.propagateWidget (enabled);
 	if (formHandle != 0) propagateHandle (enabled, formHandle, OS.None);
 	if (scrolledHandle != 0) {
 		propagateHandle (enabled, scrolledHandle, OS.None);
 		if (horizontalBar != null) horizontalBar.propagateWidget (enabled);
 		if (verticalBar != null) verticalBar.propagateWidget (enabled);
 	}
 }
 void register () {
 	super.register ();
 	if (formHandle != 0) display.addWidget (formHandle, this);
 	if (scrolledHandle != 0) display.addWidget (scrolledHandle, this);
 }
 void releaseChildren (boolean destroy) {
 	if (horizontalBar != null) {
 		horizontalBar.release (false);
 		horizontalBar = null;
 	}
 	if (verticalBar != null) {
 		verticalBar.release (false);
 		verticalBar = null;
 	}
 	super.releaseChildren (destroy);
 }
 void releaseHandle () {
 	super.releaseHandle ();
 	scrolledHandle = formHandle = 0;
 }
 void setBackgroundPixel (int pixel) {
 	super.setBackgroundPixel (pixel);
 	/*
 	* Uncomment this code to force scrollbars to change color.
 	*/
 //	if (scrolledHandle != 0) {
 //		int [] argList1 = {
 //			OS.XmNhorizontalScrollBar, 0,
 //			OS.XmNverticalScrollBar, 0,
 //		};
 //		OS.XtGetValues (scrolledHandle, argList1, argList1.length / 2);
 //		if (argList1 [1] != 0) OS.XmChangeColor (argList1 [1], pixel);
 //		if (argList1 [3] != 0) OS.XmChangeColor (argList1 [3], pixel);
 //	}
 }
 void redrawWidget (int x, int y, int width, int height, boolean redrawAll, boolean allChildren, boolean trim) {
 	super.redrawWidget (x, y, width, height, redrawAll, allChildren, trim);
 	if (!trim) return;
 	if (formHandle == 0 && scrolledHandle == 0) return;
 	short [] root_x = new short [1], root_y = new short [1];
 	OS.XtTranslateCoords (handle, (short) x, (short) y, root_x, root_y);
 	if (formHandle != 0) {
 		short [] form_x = new short [1], form_y = new short [1];
 		OS.XtTranslateCoords (formHandle, (short) 0, (short) 0, form_x, form_y);
 		redrawHandle (root_x [0] - form_x [0], root_y [0] - form_y [0], width, height, redrawAll, formHandle);
 	}
 	if (scrolledHandle != 0) {
 		short [] scrolled_x = new short [1], scrolled_y = new short [1];
 		OS.XtTranslateCoords (scrolledHandle, (short) 0, (short) 0, scrolled_x, scrolled_y);
 		redrawHandle (root_x [0] - scrolled_x [0], root_y [0] - scrolled_y [0], width, height, redrawAll, scrolledHandle);
 		if (horizontalBar != null && horizontalBar.getVisible ()) {
 			int horizontalHandle = horizontalBar.handle;
 			short [] hscroll_x = new short [1], hscroll_y = new short [1];
 			OS.XtTranslateCoords (horizontalHandle, (short) 0, (short) 0, hscroll_x, hscroll_y);
 			redrawHandle (root_x [0] - hscroll_x [0], root_y [0] - hscroll_y [0], width, height, redrawAll, horizontalHandle);
 		}
 		if (verticalBar != null && verticalBar.getVisible ()) {
 			int verticalHandle = verticalBar.handle;
 			short [] vscroll_x = new short [1], vscroll_y = new short [1];
 			OS.XtTranslateCoords (verticalHandle, (short) 0, (short) 0, vscroll_x, vscroll_y);
 			redrawHandle (root_x [0] - vscroll_x [0], root_y [0] - vscroll_y [0], width, height, redrawAll, verticalHandle);
 		}
 	}
 }
 boolean setScrollBarVisible (ScrollBar bar, boolean visible) {
 	if (scrolledHandle == 0) return false;
 	int barHandle = bar.handle;
 	boolean managed = OS.XtIsManaged (barHandle);
 	if (managed == visible) return false;

 	/*
 	* Feature in Motif.  Hiding or showing a scroll bar
 	* can cause the widget to automatically resize in
 	* the OS.  This behavior is unwanted.  The fix is
 	* to force the widget to resize to original size.
 	*/
 	int [] argList = {OS.XmNwidth, 0, OS.XmNheight, 0, OS.XmNborderWidth, 0};
 	OS.XtGetValues (scrolledHandle, argList, argList.length / 2);

 	int [] argList1 = {OS.XmNwidth, 0, OS.XmNheight, 0};
 	OS.XtGetValues (handle, argList1, argList1.length / 2);

 	/* Hide or show the scroll bar */
 	if (visible) {
 		OS.XtManageChild (barHandle);
 	} else {
 		OS.XtUnmanageChild (barHandle);
 	}
 	if ((state & CANVAS) != 0) {
 		if (formHandle != 0) {
 			boolean showBorder = (style & SWT.BORDER) != 0;
 			int margin = showBorder || visible ? 3 : 0;
 			if ((bar.style & SWT.V_SCROLL) != 0) {
 				int [] argList2 = new int [] {OS.XmNmarginWidth, margin};
 				OS.XtSetValues (formHandle, argList2, argList2.length/2);
 			}
 			if ((bar.style & SWT.H_SCROLL) != 0) {
 				int [] argList2 = new int [] {OS.XmNmarginHeight, margin};
 				OS.XtSetValues (formHandle, argList2, argList2.length/2);
 			}
 		}
 	}

 	/*
 	* Feature in Motif.  When XtSetValues() is used to restore the width and
 	* height of the widget, the new width and height are sometimes ignored.
 	* The fix is to use XtResizeWidget().
 	*/
 	OS.XtResizeWidget (scrolledHandle, argList [1], argList [3], argList [5]);

 	bar.sendEvent (visible ? SWT.Show : SWT.Hide);
 	int [] argList3 = {OS.XmNwidth, 0, OS.XmNheight, 0};
 	OS.XtGetValues (handle, argList3, argList3.length / 2);
 	return argList1 [1] != argList3 [1] || argList1 [3] != argList3 [3];
 }
 int topHandle () {
 	if (scrolledHandle != 0) return scrolledHandle;
 	if (formHandle != 0) return formHandle;
 	return handle;
 }
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2008 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.motif.*;
	import org.eclipse.swt.*;
	import org.eclipse.swt.graphics.*;

	/**
	* This class is the abstract superclass of all classes which
	* represent controls that have standard scroll bars.
	* <dl>
	* <dt><b>Styles:</b></dt>
	* <dd>H_SCROLL, V_SCROLL</dd>
	* <dt><b>Events:</b>
	* <dd>(none)</dd>
	* </dl>
	* <p>
	* IMPORTANT: This class is intended to be subclassed <em>only</em>
	* within the SWT implementation.
	* </p>
	*
	* @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 abstract class Scrollable extends Control {
	int scrolledHandle, formHandle;
	ScrollBar horizontalBar, verticalBar;
	Scrollable () {
	/* Do nothing */
	}
	/**
	* 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#H_SCROLL
	* @see SWT#V_SCROLL
	* @see Widget#checkSubclass
	* @see Widget#getStyle
	*/
	public Scrollable (Composite parent, int style) {
	super (parent, style);
	}
	/**
	* Given a desired <em>client area</em> for the receiver
	* (as described by the arguments), returns the bounding
	* rectangle which would be required to produce that client
	* area.
	* <p>
	* In other words, it returns a rectangle such that, if the
	* receiver's bounds were set to that rectangle, the area
	* of the receiver which is capable of displaying data
	* (that is, not covered by the "trimmings") would be the
	* rectangle described by the arguments (relative to the
	* receiver's parent).
	* </p>
	*
	* @param x the desired x coordinate of the client area
	* @param y the desired y coordinate of the client area
	* @param width the desired width of the client area
	* @param height the desired height of the client area
	* @return the required bounds to produce the given client area
	*
	* @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 #getClientArea
	*/
	public Rectangle computeTrim (int x, int y, int width, int height) {
	checkWidget();
	int border = getBorderWidth ();
	int trimX = x - border, trimY = y - border;
	int trimWidth = width + (border * 2), trimHeight = height + (border * 2);
	if (horizontalBar != null) {
	trimY -= display.scrolledInsetY;
	trimHeight += display.scrolledInsetY + display.scrolledMarginY;
	if (verticalBar == null) {
	trimX -= display.scrolledInsetX;
	trimWidth += display.scrolledInsetX * 2;
	trimHeight -= display.scrolledInsetY * 2;
	}
	}
	if (verticalBar != null) {
	trimX -= display.scrolledInsetX;
	trimWidth += display.scrolledInsetX + display.scrolledMarginX;
	if (horizontalBar == null) {
	trimY -= display.scrolledInsetY;
	trimHeight += display.scrolledInsetY * 2;
	trimWidth -= display.scrolledInsetX * 2;
	}
	}
	return new Rectangle (trimX, trimY, trimWidth, trimHeight);
	}
	ScrollBar createScrollBar (int type) {
	return new ScrollBar (this, type);
	}
	ScrollBar createStandardBar (int style) {
	if (scrolledHandle == 0) return null;
	ScrollBar bar = new ScrollBar ();
	bar.parent = this;
	bar.style = style;
	bar.display = display;
	int [] argList = {OS.XmNhorizontalScrollBar, 0, OS.XmNverticalScrollBar, 0};
	OS.XtGetValues (scrolledHandle, argList, argList.length / 2);
	if (style == SWT.H_SCROLL) bar.handle = argList [1];
	if (style == SWT.V_SCROLL) bar.handle = argList [3];
	bar.hookEvents ();
	bar.register ();
	return bar;
	}
	void createWidget (int index) {
	super.createWidget (index);
	if ((style & SWT.H_SCROLL) != 0) horizontalBar = createScrollBar (SWT.H_SCROLL);
	if ((style & SWT.V_SCROLL) != 0) verticalBar = createScrollBar (SWT.V_SCROLL);
	}
	void destroyScrollBar (ScrollBar bar) {
	setScrollBarVisible (bar, false);
	if ((state & CANVAS) != 0) bar.destroyHandle ();
	}
	void deregister () {
	super.deregister ();
	if (formHandle != 0) display.removeWidget (formHandle);
	if (scrolledHandle != 0) display.removeWidget (scrolledHandle);
	}
	void enableWidget (boolean enabled) {
	super.enableWidget (enabled);
	if (formHandle != 0) enableHandle (enabled, formHandle);
	if (scrolledHandle != 0) enableHandle (enabled, scrolledHandle);
	}
	/**
	* Returns a rectangle which describes the area of the
	* receiver which is capable of displaying data (that is,
	* not covered by the "trimmings").
	*
	* @return the client area
	*
	* @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 #computeTrim
	*/
	public Rectangle getClientArea () {
	checkWidget();
	int [] argList = {OS.XmNwidth, 0, OS.XmNheight, 0};
	OS.XtGetValues (handle, argList, argList.length / 2);
	return new Rectangle (0, 0, argList [1], argList [3]);
	}
	/**
	* Returns the receiver's horizontal scroll bar if it has
	* one, and null if it does not.
	*
	* @return the horizontal scroll bar (or null)
	*
	* @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 ScrollBar getHorizontalBar () {
	checkWidget();
	return horizontalBar;
	}
	/**
	* Returns the receiver's vertical scroll bar if it has
	* one, and null if it does not.
	*
	* @return the vertical scroll bar (or null)
	*
	* @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 ScrollBar getVerticalBar () {
	checkWidget();
	return verticalBar;
	}
	void manageChildren () {
	if (scrolledHandle != 0) {
	OS.XtSetMappedWhenManaged (scrolledHandle, false);
	OS.XtManageChild (scrolledHandle);
	}
	if (formHandle != 0) {
	OS.XtSetMappedWhenManaged (formHandle, false);
	OS.XtManageChild (formHandle);
	}
	super.manageChildren ();
	if (formHandle != 0) {
	int [] argList = {OS.XmNborderWidth, 0};
	OS.XtGetValues (formHandle, argList, argList.length / 2);
	OS.XtResizeWidget (formHandle, 1, 1, argList [1]);
	OS.XtSetMappedWhenManaged (formHandle, true);
	}
	if (scrolledHandle != 0) {
	int [] argList = {OS.XmNborderWidth, 0};
	OS.XtGetValues (scrolledHandle, argList, argList.length / 2);
	OS.XtResizeWidget (scrolledHandle, 1, 1, argList [1]);
	OS.XtSetMappedWhenManaged (scrolledHandle, true);
	}
	}
	void propagateWidget (boolean enabled) {
	super.propagateWidget (enabled);
	if (formHandle != 0) propagateHandle (enabled, formHandle, OS.None);
	if (scrolledHandle != 0) {
	propagateHandle (enabled, scrolledHandle, OS.None);
	if (horizontalBar != null) horizontalBar.propagateWidget (enabled);
	if (verticalBar != null) verticalBar.propagateWidget (enabled);
	}
	}
	void register () {
	super.register ();
	if (formHandle != 0) display.addWidget (formHandle, this);
	if (scrolledHandle != 0) display.addWidget (scrolledHandle, this);
	}
	void releaseChildren (boolean destroy) {
	if (horizontalBar != null) {
	horizontalBar.release (false);
	horizontalBar = null;
	}
	if (verticalBar != null) {
	verticalBar.release (false);
	verticalBar = null;
	}
	super.releaseChildren (destroy);
	}
	void releaseHandle () {
	super.releaseHandle ();
	scrolledHandle = formHandle = 0;
	}
	void setBackgroundPixel (int pixel) {
	super.setBackgroundPixel (pixel);
	/*
	* Uncomment this code to force scrollbars to change color.
	*/
	// if (scrolledHandle != 0) {
	// int [] argList1 = {
	// OS.XmNhorizontalScrollBar, 0,
	// OS.XmNverticalScrollBar, 0,
	// };
	// OS.XtGetValues (scrolledHandle, argList1, argList1.length / 2);
	// if (argList1 [1] != 0) OS.XmChangeColor (argList1 [1], pixel);
	// if (argList1 [3] != 0) OS.XmChangeColor (argList1 [3], pixel);
	// }
	}
	void redrawWidget (int x, int y, int width, int height, boolean redrawAll, boolean allChildren, boolean trim) {
	super.redrawWidget (x, y, width, height, redrawAll, allChildren, trim);
	if (!trim) return;
	if (formHandle == 0 && scrolledHandle == 0) return;
	short [] root_x = new short [1], root_y = new short [1];
	OS.XtTranslateCoords (handle, (short) x, (short) y, root_x, root_y);
	if (formHandle != 0) {
	short [] form_x = new short [1], form_y = new short [1];
	OS.XtTranslateCoords (formHandle, (short) 0, (short) 0, form_x, form_y);
	redrawHandle (root_x [0] - form_x [0], root_y [0] - form_y [0], width, height, redrawAll, formHandle);
	}
	if (scrolledHandle != 0) {
	short [] scrolled_x = new short [1], scrolled_y = new short [1];
	OS.XtTranslateCoords (scrolledHandle, (short) 0, (short) 0, scrolled_x, scrolled_y);
	redrawHandle (root_x [0] - scrolled_x [0], root_y [0] - scrolled_y [0], width, height, redrawAll, scrolledHandle);
	if (horizontalBar != null && horizontalBar.getVisible ()) {
	int horizontalHandle = horizontalBar.handle;
	short [] hscroll_x = new short [1], hscroll_y = new short [1];
	OS.XtTranslateCoords (horizontalHandle, (short) 0, (short) 0, hscroll_x, hscroll_y);
	redrawHandle (root_x [0] - hscroll_x [0], root_y [0] - hscroll_y [0], width, height, redrawAll, horizontalHandle);
	}
	if (verticalBar != null && verticalBar.getVisible ()) {
	int verticalHandle = verticalBar.handle;
	short [] vscroll_x = new short [1], vscroll_y = new short [1];
	OS.XtTranslateCoords (verticalHandle, (short) 0, (short) 0, vscroll_x, vscroll_y);
	redrawHandle (root_x [0] - vscroll_x [0], root_y [0] - vscroll_y [0], width, height, redrawAll, verticalHandle);
	}
	}
	}
	boolean setScrollBarVisible (ScrollBar bar, boolean visible) {
	if (scrolledHandle == 0) return false;
	int barHandle = bar.handle;
	boolean managed = OS.XtIsManaged (barHandle);
	if (managed == visible) return false;

	/*
	* Feature in Motif. Hiding or showing a scroll bar
	* can cause the widget to automatically resize in
	* the OS. This behavior is unwanted. The fix is
	* to force the widget to resize to original size.
	*/
	int [] argList = {OS.XmNwidth, 0, OS.XmNheight, 0, OS.XmNborderWidth, 0};
	OS.XtGetValues (scrolledHandle, argList, argList.length / 2);

	int [] argList1 = {OS.XmNwidth, 0, OS.XmNheight, 0};
	OS.XtGetValues (handle, argList1, argList1.length / 2);

	/* Hide or show the scroll bar */
	if (visible) {
	OS.XtManageChild (barHandle);
	} else {
	OS.XtUnmanageChild (barHandle);
	}
	if ((state & CANVAS) != 0) {
	if (formHandle != 0) {
	boolean showBorder = (style & SWT.BORDER) != 0;
	int margin = showBorder \|\| visible ? 3 : 0;
	if ((bar.style & SWT.V_SCROLL) != 0) {
	int [] argList2 = new int [] {OS.XmNmarginWidth, margin};
	OS.XtSetValues (formHandle, argList2, argList2.length/2);
	}
	if ((bar.style & SWT.H_SCROLL) != 0) {
	int [] argList2 = new int [] {OS.XmNmarginHeight, margin};
	OS.XtSetValues (formHandle, argList2, argList2.length/2);
	}
	}
	}

	/*
	* Feature in Motif. When XtSetValues() is used to restore the width and
	* height of the widget, the new width and height are sometimes ignored.
	* The fix is to use XtResizeWidget().
	*/
	OS.XtResizeWidget (scrolledHandle, argList [1], argList [3], argList [5]);

	bar.sendEvent (visible ? SWT.Show : SWT.Hide);
	int [] argList3 = {OS.XmNwidth, 0, OS.XmNheight, 0};
	OS.XtGetValues (handle, argList3, argList3.length / 2);
	return argList1 [1] != argList3 [1] \|\| argList1 [3] != argList3 [3];
	}
	int topHandle () {
	if (scrolledHandle != 0) return scrolledHandle;
	if (formHandle != 0) return formHandle;
	return handle;
	}
	}