Source code: org/eclipse/swt/widgets/Control.java

   /*******************************************************************************
    * 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.*;
  import org.eclipse.swt.internal.Converter;
  import org.eclipse.swt.internal.gtk.*;
  import org.eclipse.swt.graphics.*;
  import org.eclipse.swt.events.*;
  import org.eclipse.swt.accessibility.*;
  
  /**
   * Control is the abstract superclass of all windowed user interface classes.
   * <p>
   * <dl>
   * <dt><b>Styles:</b>
   * <dd>BORDER</dd>
   * <dd>LEFT_TO_RIGHT, RIGHT_TO_LEFT</dd>
   * <dt><b>Events:</b>
   * <dd>FocusIn, FocusOut, Help, KeyDown, KeyUp, MouseDoubleClick, MouseDown, MouseEnter,
   *     MouseExit, MouseHover, MouseUp, MouseMove, Move, Paint, Resize, Traverse,
   *     DragDetect, MenuDetect</dd>
   * </dl>
   * <p>
   * Only one of LEFT_TO_RIGHT or RIGHT_TO_LEFT may be specified.
   * </p><p>
   * IMPORTANT: This class is intended to be subclassed <em>only</em>
   * within the SWT implementation.
   * </p>
   */
  public abstract class Control extends Widget implements Drawable {
    long /*int*/ fixedHandle;
    long /*int*/ redrawWindow, enableWindow;
    int drawCount;
    Composite parent;
    Cursor cursor;
    Menu menu;
    Font font;
    String toolTipText;
    Object layoutData;
    Accessible accessible;
  
  Control () {
  }
  
  /**
   * 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#BORDER
   * @see Widget#checkSubclass
   * @see Widget#getStyle
   */
  public Control (Composite parent, int style) {
    super (parent, style);
    this.parent = parent;
    createWidget (0);
  }
  
  long /*int*/ defaultFont () {
    return display.defaultFont;
  }
  
  void deregister () {
    super.deregister ();
    if (fixedHandle != 0) display.removeWidget (fixedHandle);
    long /*int*/ imHandle = imHandle ();
    if (imHandle != 0) display.removeWidget (imHandle);
  }
  
 boolean drawGripper (int x, int y, int width, int height) {
   long /*int*/ paintHandle = paintHandle ();
   long /*int*/ window = OS.GTK_WIDGET_WINDOW (paintHandle);
   if (window == 0) return false;
   long /*int*/ style = OS.gtk_widget_get_style (paintHandle);
   if (style == 0) return false;
   byte[] detail = Converter.wcsToMbcs (null, "", true);
   OS.gtk_paint_handle (style, window, OS.GTK_STATE_NORMAL, OS.GTK_SHADOW_OUT, null, paintHandle, detail, x, y, width, height, OS.GTK_ORIENTATION_VERTICAL);
   return true;
 }
 
 void enableWidget (boolean enabled) {
   OS.gtk_widget_set_sensitive (handle, enabled);
 }
 
 long /*int*/ eventHandle () {
   return handle;
 }
 
 void fixFocus (Control focusControl) {
   Shell shell = getShell ();
   Control control = this;
   while ((control = control.parent) != null) {
     if (control.setFocus ()) return;
     if (control == shell) break;
   }
   shell.setSavedFocus (focusControl);
   long /*int*/ focusHandle = shell.fixedHandle;
   OS.GTK_WIDGET_SET_FLAGS (focusHandle, OS.GTK_CAN_FOCUS);
   OS.gtk_widget_grab_focus (focusHandle);
   OS.GTK_WIDGET_UNSET_FLAGS (focusHandle, OS.GTK_CAN_FOCUS);
 }
 
 long /*int*/ focusHandle () {
   return handle;
 }
 
 long /*int*/ fontHandle () {
   return handle;
 }
 
 boolean hasFocus () {
   return this == display.getFocusControl();
 }
 
 void hookEvents () {
   long /*int*/ windowProc2 = display.windowProc2;
   long /*int*/ windowProc3 = display.windowProc3;
   
   /* Connect the keyboard signals */
   long /*int*/ focusHandle = focusHandle ();
   int focusMask = OS.GDK_KEY_PRESS_MASK | OS.GDK_KEY_RELEASE_MASK | OS.GDK_FOCUS_CHANGE_MASK;
   OS.gtk_widget_add_events (focusHandle, focusMask);
   OS.g_signal_connect (focusHandle, OS.popup_menu, windowProc2, POPUP_MENU);
   OS.g_signal_connect (focusHandle, OS.show_help, windowProc3, SHOW_HELP);
   OS.g_signal_connect (focusHandle, OS.key_press_event, windowProc3, KEY_PRESS_EVENT);
   OS.g_signal_connect (focusHandle, OS.key_release_event, windowProc3, KEY_RELEASE_EVENT);
   OS.g_signal_connect (focusHandle, OS.focus, windowProc3, FOCUS);
   OS.g_signal_connect (focusHandle, OS.focus_in_event, windowProc3, FOCUS_IN_EVENT);
   OS.g_signal_connect (focusHandle, OS.focus_out_event, windowProc3, FOCUS_OUT_EVENT);
 
   /* Connect the mouse signals */
   long /*int*/ eventHandle = eventHandle ();
   int eventMask = OS.GDK_POINTER_MOTION_MASK | OS.GDK_BUTTON_PRESS_MASK |
     OS.GDK_BUTTON_RELEASE_MASK | OS.GDK_ENTER_NOTIFY_MASK |
     OS.GDK_LEAVE_NOTIFY_MASK;
   OS.gtk_widget_add_events (eventHandle, eventMask);
   OS.g_signal_connect (eventHandle, OS.button_press_event, windowProc3, BUTTON_PRESS_EVENT);
   OS.g_signal_connect (eventHandle, OS.button_release_event, windowProc3, BUTTON_RELEASE_EVENT);
   OS.g_signal_connect (eventHandle, OS.motion_notify_event, windowProc3, MOTION_NOTIFY_EVENT);
   OS.g_signal_connect (eventHandle, OS.enter_notify_event, windowProc3, ENTER_NOTIFY_EVENT);
   OS.g_signal_connect (eventHandle, OS.leave_notify_event, windowProc3, LEAVE_NOTIFY_EVENT);
   /*
   * Feature in GTK.  Events such as mouse move are propagate up
   * the widget hierarchy and are seen by the parent.  This is the
   * correct GTK behavior but not correct for SWT.  The fix is to
   * hook a signal after and stop the propagation using a negative
   * event number to distinguish this case.
   */
   OS.g_signal_connect_after (eventHandle, OS.button_press_event, windowProc3, -BUTTON_PRESS_EVENT);
   OS.g_signal_connect_after (eventHandle, OS.button_release_event, windowProc3, -BUTTON_RELEASE_EVENT);
   OS.g_signal_connect_after (eventHandle, OS.motion_notify_event, windowProc3, -MOTION_NOTIFY_EVENT);
 
   /* Connect the event_after signal for both key and mouse */
   OS.g_signal_connect (eventHandle, OS.event_after, windowProc3, EVENT_AFTER);
   if (focusHandle != eventHandle) {
     OS.g_signal_connect (focusHandle, OS.event_after, windowProc3, EVENT_AFTER);
   }
   
   /* Connect the paint signal */
   long /*int*/ paintHandle = paintHandle ();
   int paintMask = OS.GDK_EXPOSURE_MASK | OS.GDK_VISIBILITY_NOTIFY_MASK;
   OS.gtk_widget_add_events (paintHandle, paintMask);
   OS.g_signal_connect (paintHandle, OS.expose_event, windowProc3, -EXPOSE_EVENT);
   OS.g_signal_connect (paintHandle, OS.visibility_notify_event, windowProc3, VISIBILITY_NOTIFY_EVENT);
   OS.g_signal_connect_after (paintHandle, OS.expose_event, windowProc3, EXPOSE_EVENT);
 
   /* Connect the Input Method signals */
   OS.g_signal_connect_after (handle, OS.realize, windowProc2, REALIZE);
   OS.g_signal_connect (handle, OS.unrealize, windowProc2, UNREALIZE);
   long /*int*/ imHandle = imHandle ();
   if (imHandle != 0) {
     OS.g_signal_connect (imHandle, OS.commit, windowProc3, COMMIT);
     OS.g_signal_connect (imHandle, OS.preedit_changed, windowProc2, PREEDIT_CHANGED);
   }
 }
 
 long /*int*/ hoverProc (long /*int*/ widget) {
   Event event = new Event ();
   int [] x = new int [1], y = new int [1], mask = new int [1];
   OS.gdk_window_get_pointer (0, x, y, mask);
   event.x = x [0];
   event.y = y [0];
   long /*int*/ eventHandle = eventHandle ();
   long /*int*/ window = OS.GTK_WIDGET_WINDOW (eventHandle);
   OS.gdk_window_get_origin (window, x, y);
   event.x -= x [0];
   event.y -= y [0];
   setInputState (event, mask [0]);
   postEvent (SWT.MouseHover, event);
   return 0;
 }
 
 long /*int*/ topHandle() {
   if (fixedHandle != 0) return fixedHandle;
   return super.topHandle ();
 }
 
 long /*int*/ paintHandle () {
   long /*int*/ topHandle = topHandle ();
   long /*int*/ paintHandle = handle;
   while (paintHandle != topHandle) {
     if ((OS.GTK_WIDGET_FLAGS (paintHandle) & OS.GTK_NO_WINDOW) == 0) break;
     paintHandle = OS.gtk_widget_get_parent (paintHandle);
   }
   return paintHandle;
 }
 
 long /*int*/ paintWindow () {
   long /*int*/ paintHandle = paintHandle ();
   OS.gtk_widget_realize (paintHandle);
   return OS.GTK_WIDGET_WINDOW (paintHandle);
 }
 
 /**
  * Returns the preferred size of the receiver.
  * <p>
  * The <em>preferred size</em> of a control is the size that it would
  * best be displayed at. The width hint and height hint arguments
  * allow the caller to ask a control questions such as "Given a particular
  * width, how high does the control need to be to show all of the contents?"
  * To indicate that the caller does not wish to constrain a particular 
  * dimension, the constant <code>SWT.DEFAULT</code> is passed for the hint. 
  * </p>
  *
  * @param wHint the width hint (can be <code>SWT.DEFAULT</code>)
  * @param hHint the height hint (can be <code>SWT.DEFAULT</code>)
  * @return the preferred size of the control
  *
  * @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 Layout
  * @see #getBorderWidth
  * @see #getBounds
  * @see #getSize
  * @see #pack
  * @see "computeTrim, getClientArea for controls that implement them"
  */
 public Point computeSize (int wHint, int hHint) {
   return computeSize (wHint, hHint, true);
 }
 
 Control computeTabGroup () {
   if (isTabGroup()) return this;
   return parent.computeTabGroup ();
 }
 
 Control[] computeTabList() {
   if (isTabGroup()) {
     if (getVisible() && getEnabled()) {
       return new Control[] {this};
     }
   }
   return new Control[0];
 }
 
 Control computeTabRoot () {
   Control[] tabList = parent._getTabList();
   if (tabList != null) {
     int index = 0;
     while (index < tabList.length) {
       if (tabList [index] == this) break;
       index++;
     }
     if (index == tabList.length) {
       if (isTabGroup ()) return this;
     }
   }
   return parent.computeTabRoot ();
 }
 
 void createWidget (int index) {
   checkOrientation (parent);
   super.createWidget (index);
   setInitialSize ();
   setZOrder (null, false);
 }
 
 /**
  * Returns the preferred size of the receiver.
  * <p>
  * The <em>preferred size</em> of a control is the size that it would
  * best be displayed at. The width hint and height hint arguments
  * allow the caller to ask a control questions such as "Given a particular
  * width, how high does the control need to be to show all of the contents?"
  * To indicate that the caller does not wish to constrain a particular 
  * dimension, the constant <code>SWT.DEFAULT</code> is passed for the hint. 
  * </p><p>
  * If the changed flag is <code>true</code>, it indicates that the receiver's
  * <em>contents</em> have changed, therefore any caches that a layout manager
  * containing the control may have been keeping need to be flushed. When the
  * control is resized, the changed flag will be <code>false</code>, so layout
  * manager caches can be retained. 
  * </p>
  *
  * @param wHint the width hint (can be <code>SWT.DEFAULT</code>)
  * @param hHint the height hint (can be <code>SWT.DEFAULT</code>)
  * @param changed <code>true</code> if the control's contents have changed, and <code>false</code> otherwise
  * @return the preferred size of the control.
  *
  * @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 Layout
  * @see #getBorderWidth
  * @see #getBounds
  * @see #getSize
  * @see #pack
  * @see "computeTrim, getClientArea for controls that implement them"
  */
 public Point computeSize (int wHint, int hHint, boolean changed) {
   checkWidget();
   if (wHint != SWT.DEFAULT && wHint < 0) wHint = 0;
   if (hHint != SWT.DEFAULT && hHint < 0) hHint = 0;
   return computeNativeSize (handle, wHint, hHint, changed);  
 }
 
 Point computeNativeSize (long /*int*/ h, int wHint, int hHint, boolean changed) {
   int width = OS.GTK_WIDGET_WIDTH (h);
   int height = OS.GTK_WIDGET_HEIGHT (h);
   OS.gtk_widget_set_size_request (h, -1, -1);
   GtkRequisition requisition = new GtkRequisition ();
   OS.gtk_widget_size_request (h, requisition);
   OS.gtk_widget_set_size_request (h, width, height);
   width = wHint == SWT.DEFAULT ? requisition.width : wHint;
   height = hHint == SWT.DEFAULT ? requisition.height : hHint;
   return new Point (width, height);  
 }
 
 /**
  * Returns the accessible object for the receiver.
  * If this is the first time this object is requested,
  * then the object is created and returned.
  *
  * @return the accessible object
  *
  * @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 Accessible#addAccessibleListener
  * @see Accessible#addAccessibleControlListener
  * 
  * @since 2.0
  */
 public Accessible getAccessible () {
   checkWidget ();
   if (accessible == null) {
     accessible = Accessible.internal_new_Accessible (this);
   }
   return accessible;
 }
 
 /**
  * Returns a rectangle describing the receiver's size and location
  * relative to its parent (or its display if its parent is null),
  * unless the receiver is a shell. In this case, the location is
  * relative to the display.
  *
  * @return the receiver's bounding rectangle
  *
  * @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 getBounds () {
   checkWidget();
   long /*int*/ topHandle = topHandle ();
   int x = OS.GTK_WIDGET_X (topHandle);
   int y = OS.GTK_WIDGET_Y (topHandle);
   int width = OS.GTK_WIDGET_WIDTH (topHandle);
   int height = OS.GTK_WIDGET_HEIGHT (topHandle);
   return new Rectangle (x, y, width, height);
 }
 
 /**
  * Sets the receiver's size and location to the rectangular
  * area specified by the argument. The <code>x</code> and 
  * <code>y</code> fields of the rectangle are relative to
  * the receiver's parent (or its display if its parent is null).
  * <p>
  * Note: Attempting to set the width or height of the
  * receiver to a negative number will cause that
  * value to be set to zero instead.
  * </p>
  *
  * @param rect the new bounds for the receiver
  *
  * @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 setBounds (Rectangle rect) {
   checkWidget ();
   if (rect == null) error (SWT.ERROR_NULL_ARGUMENT);
   setBounds (rect.x, rect.y, rect.width, rect.height);
 }
 
 /**
  * Sets the receiver's size and location to the rectangular
  * area specified by the arguments. The <code>x</code> and 
  * <code>y</code> arguments are relative to the receiver's
  * parent (or its display if its parent is null), unless 
  * the receiver is a shell. In this case, the <code>x</code>
  * and <code>y</code> arguments are relative to the display.
  * <p>
  * Note: Attempting to set the width or height of the
  * receiver to a negative number will cause that
  * value to be set to zero instead.
  * </p>
  *
  * @param x the new x coordinate for the receiver
  * @param y the new y coordinate for the receiver
  * @param width the new width for the receiver
  * @param height the new height for the receiver
  *
  * @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 setBounds (int x, int y, int width, int height) {
   checkWidget();
   setBounds (x, y, width, height, true, true);
 }
 
 void moveHandle (int x, int y) {
   long /*int*/ topHandle = topHandle ();
   long /*int*/ parentHandle = parent.parentingHandle ();
   OS.gtk_fixed_move (parentHandle, topHandle, x, y);
 }
 
 void resizeHandle (int width, int height) {
   long /*int*/ topHandle = topHandle ();
   OS.gtk_widget_set_size_request (topHandle, width, height);
   if (topHandle != handle) {
     OS.gtk_widget_set_size_request (handle, width, height);
   }
 
   /*
   * Feature in GTK.  Some widgets do not allocate the size
   * of their internal children in gtk_widget_size_allocate().
   * Instead this is done in gtk_widget_size_request().  This
   * means that the client area of the widget is not correct.
   * The fix is to call gtk_widget_size_request() (and throw
   * the results away).
   *
   * Note: The following widgets rely on this feature:
   *   GtkScrolledWindow
   *   GtkNotebook
   *   GtkFrame
   *   GtkCombo
   */
   GtkRequisition requisition = new GtkRequisition ();
   OS.gtk_widget_size_request (handle, requisition);
 }
 
 boolean setBounds (int x, int y, int width, int height, boolean move, boolean resize) {
   long /*int*/ topHandle = topHandle ();
   int flags = OS.GTK_WIDGET_FLAGS (topHandle);
   OS.GTK_WIDGET_SET_FLAGS (topHandle, OS.GTK_VISIBLE);
   boolean sameOrigin = true, sameExtent = true;
   if (move) {
     int oldX = OS.GTK_WIDGET_X (topHandle);
     int oldY = OS.GTK_WIDGET_Y (topHandle);
     sameOrigin = x == oldX && y == oldY;
     if (!sameOrigin) {
       if (enableWindow != 0) {
         OS.gdk_window_move (enableWindow, x, y);
       }
       moveHandle (x, y);
     }
   }
   if (resize) {
     width = Math.max (1, width);
     height = Math.max (1, height);
     int oldWidth = OS.GTK_WIDGET_WIDTH (topHandle);
     int oldHeight = OS.GTK_WIDGET_HEIGHT (topHandle);
     sameExtent = width == oldWidth && height == oldHeight;
     if (!sameExtent) {
       if (redrawWindow != 0) {
         OS.gdk_window_resize (redrawWindow, width, height);
       }
       if (enableWindow != 0) {
         OS.gdk_window_resize (enableWindow, width, height);
       }
       resizeHandle (width, height);
     }
   }
   if (!sameOrigin || !sameExtent) {
     /*
     * Force the container to allocate the size of its children.
     */
     long /*int*/ parentHandle = parent.parentingHandle ();
     OS.gtk_container_resize_children (parentHandle);
   }
   if ((flags & OS.GTK_VISIBLE) == 0) {
     OS.GTK_WIDGET_UNSET_FLAGS (topHandle, OS.GTK_VISIBLE);  
   }
   if (!sameOrigin) sendEvent (SWT.Move);
   if (!sameExtent) sendEvent (SWT.Resize);
   return !sameOrigin || !sameExtent;
 }
 
 /**
  * Returns a point describing the receiver's location relative
  * to its parent (or its display if its parent is null), unless
  * the receiver is a shell. In this case, the point is 
  * relative to the display. 
  *
  * @return the receiver's location
  *
  * @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 Point getLocation () {
   checkWidget();
   long /*int*/ topHandle = topHandle ();
   int x = OS.GTK_WIDGET_X (topHandle);
   int y = OS.GTK_WIDGET_Y (topHandle);
   return new Point (x, y);
 }
 
 /**
  * Sets the receiver's location to the point specified by
  * the arguments which are relative to the receiver's
  * parent (or its display if its parent is null), unless 
  * the receiver is a shell. In this case, the point is 
  * relative to the display. 
  *
  * @param location the new location for the receiver
  *
  * @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 setLocation (Point location) {
   checkWidget ();
   if (location == null) error (SWT.ERROR_NULL_ARGUMENT);
   setLocation (location.x, location.y);
 }
 
 /**
  * Sets the receiver's location to the point specified by
  * the arguments which are relative to the receiver's
  * parent (or its display if its parent is null), unless 
  * the receiver is a shell. In this case, the point is 
  * relative to the display. 
  *
  * @param x the new x coordinate for the receiver
  * @param y the new y coordinate for the receiver
  *
  * @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 setLocation(int x, int y) {
   checkWidget();
   setBounds (x, y, 0, 0, true, false);
 }
 
 /**
  * Returns a point describing the receiver's size. The
  * x coordinate of the result is the width of the receiver.
  * The y coordinate of the result is the height of the
  * receiver.
  *
  * @return the receiver's size
  *
  * @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 Point getSize () {
   checkWidget();
   long /*int*/ topHandle = topHandle ();
   int width = OS.GTK_WIDGET_WIDTH (topHandle);
   int height = OS.GTK_WIDGET_HEIGHT (topHandle);
   return new Point (width, height);
 }
 
 /**
  * Sets the receiver's size to the point specified by the argument.
  * <p>
  * Note: Attempting to set the width or height of the
  * receiver to a negative number will cause them to be
  * set to zero instead.
  * </p>
  *
  * @param size the new size for the receiver
  *
  * @exception IllegalArgumentException <ul>
  *    <li>ERROR_NULL_ARGUMENT - if the point 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>
  */
 public void setSize (Point size) {
   checkWidget ();
   if (size == null) error (SWT.ERROR_NULL_ARGUMENT);
   setSize (size.x, size.y);
 }
 
 /**
  * Sets the receiver's size to the point specified by the arguments.
  * <p>
  * Note: Attempting to set the width or height of the
  * receiver to a negative number will cause that
  * value to be set to zero instead.
  * </p>
  *
  * @param width the new width for the receiver
  * @param height the new height for the receiver
  *
  * @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 setSize (int width, int height) {
   checkWidget();
   setBounds (0, 0, width, height, false, true);
 }
 
 /**
  * Moves the receiver above the specified control in the
  * drawing order. If the argument is null, then the receiver
  * is moved to the top of the drawing order. The control at
  * the top of the drawing order will not be covered by other
  * controls even if they occupy intersecting areas.
  *
  * @param control the sibling control (or null)
  *
  * @exception IllegalArgumentException <ul>
  *    <li>ERROR_INVALID_ARGUMENT - if the control has been disposed</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 #moveBelow
  */
 public void moveAbove (Control control) {
   checkWidget();
   if (control != null) {
     if (control.isDisposed ()) error (SWT.ERROR_INVALID_ARGUMENT);
     if (parent != control.parent) return;
   }
   setZOrder (control, true);
 }
 
 /**
  * Moves the receiver below the specified control in the
  * drawing order. If the argument is null, then the receiver
  * is moved to the bottom of the drawing order. The control at
  * the bottom of the drawing order will be covered by all other
  * controls which occupy intersecting areas.
  *
  * @param control the sibling control (or null)
  *
  * @exception IllegalArgumentException <ul>
  *    <li>ERROR_INVALID_ARGUMENT - if the control has been disposed</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 #moveAbove
  */
 public void moveBelow (Control control) {
   checkWidget();
   if (control != null) {
     if (control.isDisposed ()) error(SWT.ERROR_INVALID_ARGUMENT);
     if (parent != control.parent) return;
   }
   setZOrder (control, false);
 }
 
 /**
  * Causes the receiver to be resized to its preferred size.
  * For a composite, this involves computing the preferred size
  * from its layout, if there is one.
  *
  * @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 #computeSize
  */
 public void pack () {
   pack (true);
 }
 
 /**
  * Causes the receiver to be resized to its preferred size.
  * For a composite, this involves computing the preferred size
  * from its layout, if there is one.
  * <p>
  * If the changed flag is <code>true</code>, it indicates that the receiver's
  * <em>contents</em> have changed, therefore any caches that a layout manager
  * containing the control may have been keeping need to be flushed. When the
  * control is resized, the changed flag will be <code>false</code>, so layout
  * manager caches can be retained. 
  * </p>
  *
  * @param changed whether or not the receiver's contents have changed
  * 
  * @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 #computeSize
  */
 public void pack (boolean changed) {
   setSize (computeSize (SWT.DEFAULT, SWT.DEFAULT, changed));
 }
 
 /**
  * Sets the layout data associated with the receiver to the argument.
  * 
  * @param layoutData the new layout data for the receiver.
  * 
  * @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 setLayoutData (Object layoutData) {
   checkWidget();
   this.layoutData = layoutData;
 }
 
 /**
  * Returns a point which is the result of converting the
  * argument, which is specified in display relative coordinates,
  * to coordinates relative to the receiver.
  * <p>
  * @param x the x coordinate to be translated
  * @param y the y coordinate to be translated
  * @return the translated coordinates
  *
  * @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>
  * 
  * @since 2.1
  */
 public Point toControl (int x, int y) {
   checkWidget ();
   long /*int*/ eventHandle = eventHandle ();
   OS.gtk_widget_realize (eventHandle);
   long /*int*/ window = OS.GTK_WIDGET_WINDOW (eventHandle);
   int [] origin_x = new int [1], origin_y = new int [1];
   OS.gdk_window_get_origin (window, origin_x, origin_y);
   return new Point (x - origin_x [0], y - origin_y [0]);
 }
 
 /**
  * Returns a point which is the result of converting the
  * argument, which is specified in display relative coordinates,
  * to coordinates relative to the receiver.
  * <p>
  * @param point the point to be translated (must not be null)
  * @return the translated coordinates
  *
  * @exception IllegalArgumentException <ul>
  *    <li>ERROR_NULL_ARGUMENT - if the point 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>
  */
 public Point toControl (Point point) {
   checkWidget ();
   if (point == null) error (SWT.ERROR_NULL_ARGUMENT);
   return toControl (point.x, point.y);
 }
 
 /**
  * Returns a point which is the result of converting the
  * argument, which is specified in coordinates relative to
  * the receiver, to display relative coordinates.
  * <p>
  * @param x the x coordinate to be translated
  * @param y the y coordinate to be translated
  * @return the translated coordinates
  *
  * @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>
  * 
  * @since 2.1
  */
 public Point toDisplay (int x, int y) {
   checkWidget();
   long /*int*/ eventHandle = eventHandle ();
   OS.gtk_widget_realize (eventHandle);
   long /*int*/ window = OS.GTK_WIDGET_WINDOW (eventHandle);
   int [] origin_x = new int [1], origin_y = new int [1];
   OS.gdk_window_get_origin (window, origin_x, origin_y);
   return new Point (origin_x [0] + x, origin_y [0] + y);
 }
 
 /**
  * Returns a point which is the result of converting the
  * argument, which is specified in coordinates relative to
  * the receiver, to display relative coordinates.
  * <p>
  * @param point the point to be translated (must not be null)
  * @return the translated coordinates
  *
  * @exception IllegalArgumentException <ul>
  *    <li>ERROR_NULL_ARGUMENT - if the point 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>
  */
 public Point toDisplay (Point point) {
   checkWidget();
   if (point == null) error (SWT.ERROR_NULL_ARGUMENT);
   return toDisplay (point.x, point.y);
 }
  
 /**
  * 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 the control gains or loses focus, by sending
  * it one of the messages defined in the <code>FocusListener</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 FocusListener
  * @see #removeFocusListener
  */
 public void addFocusListener(FocusListener listener) {
   checkWidget();
   if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
   TypedListener typedListener = new TypedListener (listener);
   addListener(SWT.FocusIn,typedListener);
   addListener(SWT.FocusOut,typedListener);
 }
 
 /**
  * Adds the listener to the collection of listeners who will
  * be notified when help events are generated for the control,
  * by sending it one of the messages defined in the
  * <code>HelpListener</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 HelpListener
  * @see #removeHelpListener
  */
 public void addHelpListener (HelpListener listener) {
   checkWidget();
   if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
   TypedListener typedListener = new TypedListener (listener);
   addListener (SWT.Help, 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);
 }
 
 /**
  * Adds the listener to the collection of listeners who will
  * be notified when mouse buttons are pressed and released, by sending
  * it one of the messages defined in the <code>MouseListener</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 MouseListener
 * @see #removeMouseListener
 */
public void addMouseListener(MouseListener listener) {
  checkWidget();
  if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
  TypedListener typedListener = new TypedListener (listener);
  addListener(SWT.MouseDown,typedListener);
  addListener(SWT.MouseUp,typedListener);
  addListener(SWT.MouseDoubleClick,typedListener);
}

/**
 * Adds the listener to the collection of listeners who will
 * be notified when the mouse moves, by sending it one of the
 * messages defined in the <code>MouseMoveListener</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 MouseMoveListener
 * @see #removeMouseMoveListener
 */
public void addMouseMoveListener(MouseMoveListener listener) {
  checkWidget();
  if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
  TypedListener typedListener = new TypedListener (listener);
  addListener(SWT.MouseMove,typedListener);
}

/**
 * Adds the listener to the collection of listeners who will
 * be notified when the mouse passes or hovers over controls, by sending
 * it one of the messages defined in the <code>MouseTrackListener</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 MouseTrackListener
 * @see #removeMouseTrackListener
 */
public void addMouseTrackListener (MouseTrackListener listener) {
  checkWidget();
  if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
  TypedListener typedListener = new TypedListener (listener);
  addListener (SWT.MouseEnter,typedListener);
  addListener (SWT.MouseExit,typedListener);
  addListener (SWT.MouseHover,typedListener);
}

/**
 * Adds the listener to the collection of listeners who will
 * be notified when the receiver needs to be painted, by sending it
 * one of the messages defined in the <code>PaintListener</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 PaintListener
 * @see #removePaintListener
 */
public void addPaintListener(PaintListener listener) {
  checkWidget();
  if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
  TypedListener typedListener = new TypedListener (listener);
  addListener(SWT.Paint,typedListener);
}

/**
 * Adds the listener to the collection of listeners who will
 * be notified when traversal events occur, by sending it
 * one of the messages defined in the <code>TraverseListener</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 TraverseListener
 * @see #removeTraverseListener
 */
public void addTraverseListener (TraverseListener listener) {
  checkWidget();
  if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
  TypedListener typedListener = new TypedListener (listener);
  addListener (SWT.Traverse,typedListener);
}

/**
 * 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 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.Move, listener);
  eventTable.unhook (SWT.Resize, listener);
}
/**
 * Removes the listener from the collection of listeners who will
 * be notified when the control gains or loses focus.
 *
 * @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 FocusListener
 * @see #addFocusListener
 */
public void removeFocusListener(FocusListener listener) {
  checkWidget();
  if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
  if (eventTable == null) return;
  eventTable.unhook (SWT.FocusIn, listener);
  eventTable.unhook (SWT.FocusOut, listener);
}
/**
 * Removes the listener from the collection of listeners who will
 * be notified when the help events are generated for the control.
 *
 * @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 HelpListener
 * @see #addHelpListener
 */
public void removeHelpListener (HelpListener listener) {
  checkWidget();
  if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
  if (eventTable == null) return;
  eventTable.unhook (SWT.Help, 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 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);
}
/**
 * Removes the listener from the collection of listeners who will
 * be notified when mouse buttons are pressed and released.
 *
 * @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 MouseListener
 * @see #addMouseListener
 */
public void removeMouseListener (MouseListener listener) {
  checkWidget();
  if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
  if (eventTable == null) return;
  eventTable.unhook (SWT.MouseDown, listener);
  eventTable.unhook (SWT.MouseUp, listener);
  eventTable.unhook (SWT.MouseDoubleClick, listener);
}
/**
 * Removes the listener from the collection of listeners who will
 * be notified when the mouse moves.
 *
 * @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 MouseMoveListener
 * @see #addMouseMoveListener
 */
public void removeMouseMoveListener(MouseMoveListener listener) {
  checkWidget();
  if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
  if (eventTable == null) return;
  eventTable.unhook (SWT.MouseMove, listener);
}

/**
 * Removes the listener from the collection of listeners who will
 * be notified when the mouse passes or hovers over controls.
 *
 * @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 MouseTrackListener
 * @see #addMouseTrackListener
 */
public void removeMouseTrackListener(MouseTrackListener listener) {
  checkWidget();
  if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
  if (eventTable == null) return;
  eventTable.unhook (SWT.MouseEnter, listener);
  eventTable.unhook (SWT.MouseExit, listener);
  eventTable.unhook (SWT.MouseHover, listener);
}

/**
 * Removes the listener from the collection of listeners who will
 * be notified when the receiver needs to be painted.
 *
 * @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 PaintListener
 * @see #addPaintListener
 */
public void removePaintListener(PaintListener listener) {
  checkWidget();
  if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
  if (eventTable == null) return;
  eventTable.unhook(SWT.Paint, listener);
}

/**
 * Removes the listener from the collection of listeners who will
 * be notified when traversal events occur.
 *
 * @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 TraverseListener
 * @see #addTraverseListener
 */
public void removeTraverseListener(TraverseListener listener) {
  checkWidget ();
  if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
  if (eventTable == null) return;
  eventTable.unhook (SWT.Traverse, listener);
}

boolean filterKey (int keyval, long /*int*/ event) {
  long /*int*/ imHandle = imHandle ();
  if (imHandle != 0) {
    return OS.gtk_im_context_filter_keypress (imHandle, event);
  }
  return false;
}

Menu [] findMenus (Control control) {
  if (menu != null && this != control) return new Menu [] {menu};
  return new Menu [0];
}

void fixChildren (Shell newShell, Shell oldShell, Decorations newDecorations, Decorations oldDecorations, Menu [] menus) {
  oldShell.fixShell (newShell, this);
  oldDecorations.fixDecorations (newDecorations, this, menus);
}

/**
 * Forces the receiver to have the <em>keyboard focus</em>, causing
 * all keyboard events to be delivered to it.
 *
 * @return <code>true</code> if the control got focus, and <code>false</code> if it was unable to.
 *
 * @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 #setFocus
 */
public boolean forceFocus () {
  checkWidget();
  Shell shell = getShell ();
  shell.setSavedFocus (this);
  if (!isEnabled () || !isVisible ()) return false;
  shell.bringToTop (false);
  return forceFocus (focusHandle ());
}

boolean forceFocus (long /*int*/ focusHandle) {
  OS.gtk_widget_grab_focus (focusHandle);
  return this == display.getFocusControl();
}

/**
 * Returns the receiver's background color.
 *
 * @return the background color
 *
 * @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 Color getBackground () {
  checkWidget();
  return Color.gtk_new (display, getBackgroundColor ());
}

GdkColor getBackgroundColor () {
  return getBgColor ();
}

GdkColor getBgColor () {
  long /*int*/ fontHandle = fontHandle ();
  OS.gtk_widget_realize (fontHandle);
  GdkColor color = new GdkColor ();
  OS.gtk_style_get_bg (OS.gtk_widget_get_style (fontHandle), OS.GTK_STATE_NORMAL, color);
  return color;
}

GdkColor getBaseColor () {
  long /*int*/ fontHandle = fontHandle ();
  OS.gtk_widget_realize (fontHandle);
  GdkColor color = new GdkColor ();
  OS.gtk_style_get_base (OS.gtk_widget_get_style (fontHandle), OS.GTK_STATE_NORMAL, color);
  return color;
}

/**
 * Returns the receiver's border width.
 *
 * @return the border width
 *
 * @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 int getBorderWidth () {
  checkWidget();
  return 0;
}

/**
 * Returns <code>true</code> if the receiver is enabled, and
 * <code>false</code> otherwise. A disabled control is typically
 * not selectable from the user interface and draws with an
 * inactive or "grayed" look.
 *
 * @return the receiver's enabled state
 *
 * @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 #isEnabled
 */
public boolean getEnabled () {
  checkWidget ();
  return (state & DISABLED) == 0;
}

/**
 * Returns the font that the receiver will use to paint textual information.
 *
 * @return the receiver's font
 *
 * @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 Font getFont () {
  checkWidget();
  if (font != null) return font;
  return Font.gtk_new (display, defaultFont ());
}
  
long /*int*/ getFontDescription () {
  long /*int*/ fontHandle = fontHandle ();
  return OS.gtk_style_get_font_desc (OS.gtk_widget_get_style (fontHandle));
}

/**
 * Returns the foreground color that the receiver will use to draw.
 *
 * @return the receiver's foreground color
 *
 * @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 Color getForeground () {
  checkWidget();
  return Color.gtk_new (display, getForegroundColor ());
}

GdkColor getForegroundColor () {
  return getFgColor ();
}

GdkColor getFgColor () {
  long /*int*/ fontHandle = fontHandle ();
  OS.gtk_widget_realize (fontHandle);
  GdkColor color = new GdkColor ();
  OS.gtk_style_get_fg (OS.gtk_widget_get_style (fontHandle), OS.GTK_STATE_NORMAL, color);
  return color;
}

Point getIMCaretPos () {
  return new Point (0, 0);
}

GdkColor getTextColor () {
  long /*int*/ fontHandle = fontHandle ();
  OS.gtk_widget_realize (fontHandle);
  GdkColor color = new GdkColor ();
  OS.gtk_style_get_text (OS.gtk_widget_get_style (fontHandle), OS.GTK_STATE_NORMAL, color);
  return color;
}

/**
 * Returns layout data which is associated with the receiver.
 *
 * @return the receiver's layout data
 *
 * @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 Object getLayoutData () {
  checkWidget();
  return layoutData;
}

/**
 * Returns the receiver's pop up menu if it has one, or null
 * if it does not. All controls may optionally have a pop up
 * menu that is displayed when the user requests one for
 * the control. The sequence of key strokes, button presses
 * and/or button releases that are used to request a pop up
 * menu is platform specific.
 *
 * @return the receiver's menu
 *
 * @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 Menu getMenu () {
  checkWidget();
  return menu;
}

/**
 * Returns the receiver's monitor.
 * 
 * @return the receiver's monitor
 * 
 * @since 3.0
 */
public Monitor getMonitor () {
  checkWidget();
  Monitor monitor = null;
  long /*int*/ screen = OS.gdk_screen_get_default ();
  if (screen != 0) {
    int monitorNumber = OS.gdk_screen_get_monitor_at_window (screen, paintWindow ());
    GdkRectangle dest = new GdkRectangle ();
    OS.gdk_screen_get_monitor_geometry (screen, monitorNumber, dest);
    monitor = new Monitor ();
    monitor.handle = monitorNumber;
    monitor.x = dest.x;
    monitor.y = dest.y;
    monitor.width = dest.width;
    monitor.height = dest.height;
    monitor.clientX = monitor.x;
    monitor.clientY = monitor.y;
    monitor.clientWidth = monitor.width;
    monitor.clientHeight = monitor.height;
  } else {
    monitor = display.getPrimaryMonitor ();
  }
  return monitor;
}

/**
 * Returns the receiver's parent, which must be a <code>Composite</code>
 * or null when the receiver is a shell that was created with null or
 * a display for a parent.
 *
 * @return the receiver's parent
 *
 * @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 Composite getParent () {
  checkWidget();
  return parent;
}

Control [] getPath () {
  int count = 0;
  Shell shell = getShell ();
  Control control = this;
  while (control != shell) {
    count++;
    control = control.parent;
  }
  control = this;
  Control [] result = new Control [count];
  while (control != shell) {
    result [--count] = control;
    control = control.parent;
  }
  return result;
}

/**
 * Returns the receiver's shell. For all controls other than
 * shells, this simply returns the control's nearest ancestor
 * shell. Shells return themselves, even if they are children
 * of other shells.
 *
 * @return the receiver's shell
 *
 * @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 #getParent
 */
public Shell getShell() {
  checkWidget();
  return _getShell();
}
Shell _getShell() {
  return parent._getShell();
}

/**
 * Returns the receiver's tool tip text, or null if it has
 * not been set.
 *
 * @return the receiver's tool tip text
 *
 * @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 String getToolTipText () {
  checkWidget();
  return toolTipText;
}
/**
 * Returns <code>true</code> if the receiver is visible, and
 * <code>false</code> otherwise.
 * <p>
 * If one of the receiver's ancestors is not visible or some
 * other condition makes the receiver not visible, this method
 * may still indicate that it is considered visible even though
 * it may not actually be showing.
 * </p>
 *
 * @return the receiver's visibility state
 *
 * @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 getVisible () {
  checkWidget();
  return OS.GTK_WIDGET_VISIBLE (topHandle ()); 
}

long /*int*/ gtk_button_press_event (long /*int*/ widget, long /*int*/ event) {
  Shell shell = _getShell ();
  GdkEventButton gdkEvent = new GdkEventButton ();
  OS.memmove (gdkEvent, event, GdkEventButton.sizeof);
  if (gdkEvent.type == OS.GDK_3BUTTON_PRESS) return 0;
  display.dragStartX = (int) gdkEvent.x;
  display.dragStartY = (int) gdkEvent.y;
  display.dragging = false;
  int button = gdkEvent.button;
  int type = gdkEvent.type != OS.GDK_2BUTTON_PRESS ? SWT.MouseDown : SWT.MouseDoubleClick;
  sendMouseEvent (type, button, event);
  int result = 0;
  if ((state & MENU) != 0) {
    if (gdkEvent.button == 3 && gdkEvent.type == OS.GDK_BUTTON_PRESS) {
      if (showMenu ((int)gdkEvent.x_root, (int)gdkEvent.y_root)) {
        result = 1;
      }
    }
  }  
  
  /*
  * It is possible that the shell may be
  * disposed at this point.  If this happens
  * don't send the activate and deactivate
  * events.
  */  
  if (!shell.isDisposed ()) {
    shell.setActiveControl (this);
  }
  return result;
}

long /*int*/ gtk_button_release_event (long /*int*/ widget, long /*int*/ event) {
  GdkEventButton gdkEvent = new GdkEventButton ();
  OS.memmove (gdkEvent, event, GdkEventButton.sizeof);
  sendMouseEvent (SWT.MouseUp, gdkEvent.button, event);
  return 0;
}

long /*int*/ gtk_commit (long /*int*/ imcontext, long /*int*/ text) {
  if (text == 0) return 0;
  int length = OS.strlen (text);
  if (length == 0) return 0;
  byte [] buffer = new byte [length];
  OS.memmove (buffer, text, length);
  char [] chars = Converter.mbcsToWcs (null, buffer);
  sendIMKeyEvent (SWT.KeyDown, null, chars);
  return 0;
}

long /*int*/ gtk_enter_notify_event (long /*int*/ widget, long /*int*/ event) {
  GdkEventCrossing gdkEvent = new GdkEventCrossing ();
  OS.memmove (gdkEvent, event, GdkEventCrossing.sizeof);
  if (gdkEvent.mode != OS.GDK_CROSSING_NORMAL) return 0;
  if (gdkEvent.subwindow != 0) return 0;
  sendMouseEvent (SWT.MouseEnter, 0, event);
  return 0;
}

long /*int*/ gtk_event_after (long /*int*/ widget, long /*int*/ gdkEvent) {
  GdkEvent event = new GdkEvent ();
  OS.memmove (event, gdkEvent, GdkEvent.sizeof);
  switch (event.type) {
    case OS.GDK_BUTTON_PRESS: {
      if ((state & MENU) == 0) {
        GdkEventButton gdkEventButton = new GdkEventButton ();
        OS.memmove (gdkEventButton, gdkEvent, GdkEventButton.sizeof);
        if (gdkEventButton.button == 3) {
          showMenu ((int) gdkEventButton.x_root, (int) gdkEventButton.y_root);
        }
      }
      break;
    }
    case OS.GDK_FOCUS_CHANGE: {
      GdkEventFocus gdkEventFocus = new GdkEventFocus ();
      OS.memmove (gdkEventFocus, gdkEvent, GdkEventFocus.sizeof);
      sendFocusEvent (gdkEventFocus.in != 0 ? SWT.FocusIn : SWT.FocusOut);
      break;
    }
  }
  return 0;
}
  
long /*int*/ gtk_expose_event (long /*int*/ widget, long /*int*/ eventPtr) {
  if ((state & OBSCURED) != 0) return 0;
  if (!hooks (SWT.Paint) && !filters (SWT.Paint)) return 0;
  GdkEventExpose gdkEvent = new GdkEventExpose ();
  OS.memmove(gdkEvent, eventPtr, GdkEventExpose.sizeof);
  Event event = new Event ();
  event.count = gdkEvent.count;
  event.x = gdkEvent.area_x;
  event.y = gdkEvent.area_y;
  event.width = gdkEvent.area_width;
  event.height = gdkEvent.area_height;
  GC gc = event.gc = new GC (this);
  Region region = Region.gtk_new (display, gdkEvent.region);
  gc.setClipping (region);
  sendEvent (SWT.Paint, event);
  gc.dispose ();
  event.gc = null;
  return 0;
}

long /*int*/ gtk_focus (long /*int*/ widget, long /*int*/ directionType) {
  /* Stop GTK traversal for every widget */
  return 1;
}

long /*int*/ gtk_focus_in_event (long /*int*/ widget, long /*int*/ event) {
  // widget could be disposed at this point
  if (handle != 0) {
    Control oldControl = display.imControl;
    if (oldControl != this)  {
      if (oldControl != null && !oldControl.isDisposed ()) {
        long /*int*/ oldIMHandle = oldControl.imHandle ();
        if (oldIMHandle != 0) OS.gtk_im_context_reset (oldIMHandle);
      }
    }
    if (hooks (SWT.KeyDown) || hooks (SWT.KeyUp)) {
      long /*int*/ imHandle = imHandle ();
      if (imHandle != 0) OS.gtk_im_context_focus_in (imHandle);
    }
  }
  return 0;
}

long /*int*/ gtk_focus_out_event (long /*int*/ widget, long /*int*/ event) {
  // widget could be disposed at this point
  if (handle != 0) {
    if (hooks (SWT.KeyDown) || hooks (SWT.KeyUp)) {
      long /*int*/ imHandle = imHandle ();
      if (imHandle != 0) {
        OS.gtk_im_context_focus_out (imHandle);
      }
    }
  }
  return 0;
}

long /*int*/ gtk_key_press_event (long /*int*/ widget, long /*int*/ event) {
  if (!hasFocus ()) return 0;
  GdkEventKey gdkEvent = new GdkEventKey ();
  OS.memmove (gdkEvent, event, GdkEventKey.sizeof);
  
  if (translateMnemonic (gdkEvent.keyval, gdkEvent)) return 1;
  // widget could be disposed at this point
  if (isDisposed ()) return 0;
  
  if (filterKey (gdkEvent.keyval, event)) return 1;
  // widget could be disposed at this point
  if (isDisposed ()) return 0;  
  
  if (translateTraversal (gdkEvent)) return 1;
  // widget could be disposed at this point
  if (isDisposed ()) return 0;
  return sendKeyEvent (SWT.KeyDown, gdkEvent) ? 0 : 1;
}

long /*int*/ gtk_key_release_event (long /*int*/ widget, long /*int*/ event) {
  if (!hasFocus ()) return 0;
  long /*int*/ imHandle = imHandle ();
  if (imHandle != 0) {
    if (OS.gtk_im_context_filter_keypress (imHandle, event)) return 1;
  }
  GdkEventKey gdkEvent = new GdkEventKey ();
  OS.memmove (gdkEvent, event, GdkEventKey.sizeof);
  return sendKeyEvent (SWT.KeyUp, gdkEvent) ? 0 : 1;
}

long /*int*/ gtk_leave_notify_event (long /*int*/ widget, long /*int*/ event) {
  display.removeMouseHoverTimeout (handle);
  GdkEventCrossing gdkEvent = new GdkEventCrossing ();
  OS.memmove (gdkEvent, event, GdkEventCrossing.sizeof);
  if (gdkEvent.mode != OS.GDK_CROSSING_NORMAL) return 0;
  if (gdkEvent.subwindow != 0) return 0;
  sendMouseEvent (SWT.MouseExit, 0, event);
  return 0;
}

long /*int*/ gtk_mnemonic_activate (long /*int*/ widget, long /*int*/ arg1) {
  int result = 0;
  long /*int*/ eventPtr = OS.gtk_get_current_event ();
  if (eventPtr != 0) {
    GdkEventKey keyEvent = new GdkEventKey ();
    OS.memmove (keyEvent, eventPtr, GdkEventKey.sizeof);
    if (keyEvent.type == OS.GDK_KEY_PRESS) {
      Control focusControl = display.getFocusControl ();
      long /*int*/ focusHandle = focusControl != null ? focusControl.focusHandle () : 0;
      if (focusHandle != 0) {
        display.mnemonicControl = this;
        OS.gtk_widget_event (focusHandle, eventPtr);
        display.mnemonicControl = null;
      }
      result = 1;
    }
    OS.gdk_event_free (eventPtr);
  }
  return result;
}

long /*int*/ gtk_motion_notify_event (long /*int*/ widget, long /*int*/ event) {
  if (hooks (SWT.DragDetect)) {
    if (!display.dragging) {
      int []  state = new int [1];
      OS.gdk_event_get_state (event, state);
      if ((state [0] & OS.GDK_BUTTON1_MASK) != 0) {
        double [] px = new double [1], py = new double [1];
        OS.gdk_event_get_coords (event, px, py);
        if (OS.gtk_drag_check_threshold (handle, display.dragStartX, display.dragStartY, (int) px [0], (int) py [0])){
          display.dragging = true;
          Event e = new Event ();
          e.x = display.dragStartX;
          e.y = display.dragStartY;
          postEvent (SWT.DragDetect, e);
        }
      }
    }
  }
  if (hooks (SWT.MouseHover) || filters (SWT.MouseHover)) {
    display.addMouseHoverTimeout (handle);
  }
  sendMouseEvent (SWT.MouseMove, 0, event);
  return 0;
}

long /*int*/ gtk_popup_menu (long /*int*/ widget) {
  if (!hasFocus()) return 0;
  int [] x = new int [1], y = new int [1];
  OS.gdk_window_get_pointer (0, x, y, null);
  showMenu (x [0], y [0]);
  return 0;
}

long /*int*/ gtk_preedit_changed (long /*int*/ imcontext) {
  display.showIMWindow (this);
  return 0;
}

long /*int*/ gtk_realize (long /*int*/ widget) {
  long /*int*/ imHandle = imHandle ();
  if (imHandle != 0) {
    long /*int*/ window = OS.GTK_WIDGET_WINDOW (paintHandle ());
    OS.gtk_im_context_set_client_window (imHandle, window);
  }
  return 0;
}

long /*int*/ gtk_show_help (long /*int*/ widget, long /*int*/ helpType) {
  if (!hasFocus ()) return 0;
  return sendHelpEvent (helpType) ? 1 : 0;
}

long /*int*/ gtk_unrealize (long /*int*/ widget) {
  long /*int*/ imHandle = imHandle ();
  if (imHandle != 0) OS.gtk_im_context_set_client_window (imHandle, 0);
  return 0;  
}

long /*int*/ gtk_visibility_notify_event (long /*int*/ widget, long /*int*/ event) {
  GdkEventVisibility gdkEvent = new GdkEventVisibility ();
  OS.memmove (gdkEvent, event, GdkEventVisibility.sizeof);
  if (gdkEvent.state == OS.GDK_VISIBILITY_FULLY_OBSCURED) {
    state |= OBSCURED;
  } else {
    if ((state & OBSCURED) != 0) {
      long /*int*/ paintHandle = paintHandle ();
      int width = OS.GTK_WIDGET_WIDTH (paintHandle);
      int height = OS.GTK_WIDGET_HEIGHT (paintHandle);
      redrawWidget (0, 0, width, height, false);
    }
    state &= ~OBSCURED;
  }
  return 0;
}

/**   
 * Invokes platform specific functionality to allocate a new GC handle.
 * <p>
 * <b>IMPORTANT:</b> This method is <em>not</em> part of the public
 * API for <code>Control</code>. It is marked public only so that it
 * can be shared within the packages provided by SWT. It is not
 * available on all platforms, and should never be called from
 * application code.
 * </p>
 *
 * @param data the platform specific GC data 
 * @return the platform specific GC handle
 */
public long /*int*/ internal_new_GC (GCData data) {
  checkWidget ();
  long /*int*/ window = paintWindow ();
  if (window == 0) SWT.error (SWT.ERROR_NO_HANDLES);
  long /*int*/ gdkGC = OS.gdk_gc_new (window);
  if (gdkGC == 0) error (SWT.ERROR_NO_HANDLES);  
  if (data != null) {
    int mask = SWT.LEFT_TO_RIGHT | SWT.RIGHT_TO_LEFT;
    if ((data.style & mask) == 0) {
      data.style |= style & (mask | SWT.MIRRORED);
    }
    data.drawable = window;
    data.device = display;
    data.background = getBackgroundColor ();
    data.foreground = getForegroundColor ();
    data.font = font != null ? font.handle : defaultFont (); 
  }  
  return gdkGC;
}

long /*int*/ imHandle () {
  return 0;
}

/**   
 * Invokes platform specific functionality to dispose a GC handle.
 * <p>
 * <b>IMPORTANT:</b> This method is <em>not</em> part of the public
 * API for <code>Control</code>. It is marked public only so that it
 * can be shared within the packages provided by SWT. It is not
 * available on all platforms, and should never be called from
 * application code.
 * </p>
 *
 * @param hDC the platform specific GC handle
 * @param data the platform specific GC data 
 */
public void internal_dispose_GC (long /*int*/ gdkGC, GCData data) {
  checkWidget ();
  OS.g_object_unref (gdkGC);
}

/**
 * Returns <code>true</code> if the underlying operating
 * system supports this reparenting, otherwise <code>false</code>
 *
 * @return <code>true</code> if the widget can be reparented, otherwise <code>false</code>
 *
 * @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 isReparentable () {
  checkWidget();
  return true;
}
boolean isShowing () {
  /*
  * This is not complete.  Need to check if the
  * widget is obscurred by a parent or sibling.
  */
  if (!isVisible ()) return false;
  Control control = this;
  while (control != null) {
    Point size = control.getSize ();
    if (size.x == 1 || size.y == 1) {
      return false;
    }
    control = control.parent;
  }
  return true;
}
boolean isTabGroup () {
  Control [] tabList = parent._getTabList ();
  if (tabList != null) {
    for (int i=0; i<tabList.length; i++) {
      if (tabList [i] == this) return true;
    }
  }
  int code = traversalCode (0, null);
  if ((code & (SWT.TRAVERSE_ARROW_PREVIOUS | SWT.TRAVERSE_ARROW_NEXT)) != 0) return false;
  return (code & (SWT.TRAVERSE_TAB_PREVIOUS | SWT.TRAVERSE_TAB_NEXT)) != 0;
}
boolean isTabItem () {
  Control [] tabList = parent._getTabList ();
  if (tabList != null) {
    for (int i=0; i<tabList.length; i++) {
      if (tabList [i] == this) return false;
    }
  }
  int code = traversalCode (0, null);
  return (code & (SWT.TRAVERSE_ARROW_PREVIOUS | SWT.TRAVERSE_ARROW_NEXT)) != 0;
}

/**
 * Returns <code>true</code> if the receiver is enabled and all
 * of the receiver's ancestors are enabled, and <code>false</code>
 * otherwise. A disabled control is typically not selectable from the
 * user interface and draws with an inactive or "grayed" look.
 *
 * @return the receiver's enabled state
 *
 * @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 #getEnabled
 */
public boolean isEnabled () {
  checkWidget ();
  return getEnabled () && parent.isEnabled ();
}

boolean isFocusAncestor (Control control) {
  while (control != null && control != this) {
    control = control.parent;
  }
  return control == this;
}

/**
 * Returns <code>true</code> if the receiver has the user-interface
 * focus, and <code>false</code> otherwise.
 *
 * @return the receiver's focus state
 *
 * @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 isFocusControl () {
  checkWidget();
  return hasFocus ();
}

/**
 * Returns <code>true</code> if the receiver is visible and all
 * of the receiver's ancestors are visible and <code>false</code>
 * otherwise.
 *
 * @return the receiver's visibility state
 *
 * @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 #getVisible
 */
public boolean isVisible () {
  checkWidget();
  return getVisible () && parent.isVisible ();
}

Decorations menuShell () {
  return parent.menuShell ();
}

boolean mnemonicHit (char key) {
  return false;
}

boolean mnemonicMatch (char key) {
  return false;
}

void register () {
  super.register ();
  if (fixedHandle != 0) display.addWidget (fixedHandle, this);
  long /*int*/ imHandle = imHandle ();
  if (imHandle != 0) display.addWidget (imHandle, this);
}

/**
 * Causes the entire bounds of the receiver to be marked
 * as needing to be redrawn. The next time a paint request
 * is processed, the control will be completely painted,
 * including the background.
 *
 * @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 #update
 * @see PaintListener
 * @see SWT#Paint
 * @see SWT#NO_BACKGROUND
 * @see SWT#NO_REDRAW_RESIZE
 * @see SWT#NO_MERGE_PAINTS
 */
public void redraw () {
  checkWidget();
  long /*int*/ paintHandle = paintHandle ();
  int width = OS.GTK_WIDGET_WIDTH (paintHandle);
  int height = OS.GTK_WIDGET_HEIGHT (paintHandle);
  redrawWidget (0, 0, width, height, true);
}
/**
 * Causes the rectangular area of the receiver specified by
 * the arguments to be marked as needing to be redrawn. 
 * The next time a paint request is processed, that area of
 * the receiver will be painted, including the background.
 * If the <code>all</code> flag is <code>true</code>, any
 * children of the receiver which intersect with the specified
 * area will also paint their intersecting areas. If the
 * <code>all</code> flag is <code>false</code>, the children
 * will not be painted.
 *
 * @param x the x coordinate of the area to draw
 * @param y the y coordinate of the area to draw
 * @param width the width of the area to draw
 * @param height the height of the area to draw
 * @param all <code>true</code> if children should redraw, and <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>
 *
 * @see #update
 * @see PaintListener
 * @see SWT#Paint
 * @see SWT#NO_BACKGROUND
 * @see SWT#NO_REDRAW_RESIZE
 * @see SWT#NO_MERGE_PAINTS
 */
public void redraw (int x, int y, int width, int height, boolean all) {
  checkWidget();
  redrawWidget (x, y, width, height, all);
}

void redrawWidget (int x, int y, int width, int height, boolean all) {
  if ((OS.GTK_WIDGET_FLAGS (handle) & OS.GTK_REALIZED) == 0) return;
  long /*int*/ window = paintWindow ();
  GdkRectangle rect = new GdkRectangle ();
  rect.x = x;
  rect.y = y;
  rect.width = width;
  rect.height = height;
  OS.gdk_window_invalidate_rect (window, rect, all);
}

void releaseChild () {
  parent.removeControl (this);
}

void releaseHandle () {
  super.releaseHandle ();
  fixedHandle = 0;
}

void releaseWidget () {
  display.removeMouseHoverTimeout (handle);
  super.releaseWidget ();
  long /*int*/ imHandle = imHandle ();
  if (imHandle != 0) {
    OS.gtk_im_context_reset (imHandle);
    OS.gtk_im_context_set_client_window (imHandle, 0);
  }
  if (enableWindow != 0) {
    OS.gdk_window_set_user_data (enableWindow, 0);
    OS.gdk_window_destroy (enableWindow);
    enableWindow = 0;
  }
  if (menu != null && !menu.isDisposed ()) {
    menu.dispose ();
  }
  menu = null;
  cursor = null;
  toolTipText = null;
  parent = null;
  layoutData = null;
  accessible = null;
}

void sendFocusEvent (int type) {
  Shell shell = _getShell ();
  sendEvent (type);
  switch (type) {
    case SWT.FocusIn: {
      /*
      * It is possible that the shell may be
      * disposed at this point.  If this happens
      * don't send the activate and deactivate
      * events.
      */
      if (!shell.isDisposed ()) {
        shell.setActiveControl (this);
      }      
      break;
    }
    case SWT.FocusOut: {
      /*
      * It is possible that the shell may be
      * disposed at this point.  If this happens
      * don't send the activate and deactivate
      * events.
      */
      if (!shell.isDisposed ()) {
        Display display = shell.display;
        Control control = display.getFocusControl ();
        if (control == null || shell != control.getShell () ) {
          shell.setActiveControl (null);
        }
      }
      break;
    }
  }
}

boolean sendHelpEvent (long /*int*/ helpType) {
  Control control = this;
  while (control != null) {
    if (control.hooks (SWT.Help)) {
      control.postEvent (SWT.Help);
      return true;
    }
    control = control.parent;
  }
  return false;
}

char [] sendIMKeyEvent (int type, GdkEventKey keyEvent, char  [] chars) {
  int index = 0, count = 0, state = 0, time = 0;
  if (keyEvent == null) {
    long /*int*/ ptr = OS.gtk_get_current_event ();
    if (ptr != 0) {
      keyEvent = new GdkEventKey ();
      OS.memmove (keyEvent, ptr, GdkEventKey.sizeof);
      OS.gdk_event_free (ptr);
      switch (keyEvent.type) {
        case OS.GDK_KEY_PRESS:
        case OS.GDK_KEY_RELEASE:
          state = keyEvent.state;
          time =  keyEvent.time;
          break;
        default:
          keyEvent = null;
          break;
      }
    }
  }
  if (keyEvent == null) {
    int [] buffer = new int [1];
    OS.gtk_get_current_event_state (buffer);
    state = buffer [0];
    time = OS.gtk_get_current_event_time();
  }
  while (index < chars.length) {
    Event event = new Event ();
    event.time = time;
    if (keyEvent != null && keyEvent.length <= 1) {
      setKeyState (event, keyEvent);
    } else {
      setInputState (event, state);
    }
    event.character = chars [index];
    sendEvent (type, event);
  
    /*
    * It is possible (but unlikely), that application
    * code could have disposed the widget in the key
    * events.  If this happens, end the processing of
    * the key by returning null.
    */
    if (isDisposed ()) return null;
    if (event.doit) chars [count++] = chars [index];
    index++;
  }
  if (count == 0) return null;
  if (index != count) {
    char [] result = new char [count];
    System.arraycopy (chars, 0, result, 0, count);
    return result;
  }
  return chars;
}

boolean sendKeyEvent (int type, GdkEventKey keyEvent) {
  int length = keyEvent.length;
  if (length <= 1) {
    Event event = new Event ();
    event.time = keyEvent.time;
    if (!setKeyState (event, keyEvent)) return true;
    sendEvent (type, event);
    // widget could be disposed at this point
  
    /*
    * It is possible (but unlikely), that application
    * code could have disposed the widget in the key
    * events.  If this happens, end the processing of
    * the key by returning false.
    */
    if (isDisposed ()) return false;
    return event.doit;
  }
  byte [] buffer = new byte [length];
  OS.memmove (buffer, keyEvent.string, length);
  char [] chars = Converter.mbcsToWcs (null, buffer);
  return sendIMKeyEvent (type, keyEvent, chars) != null;
}

void sendMouseEvent (int type, int button, long /*int*/ eventPtr) {
  Event event = new Event ();
  event.time = OS.gdk_event_get_time (eventPtr);
  event.button = button;
  if (type == SWT.MouseMove) {
    GdkEventMotion gdkEvent = new GdkEventMotion ();
    OS.memmove (gdkEvent, eventPtr, GdkEventMotion.sizeof);
    if (gdkEvent.is_hint != 0) {
      int [] pointer_x = new int [1], pointer_y = new int [1];
      OS.gdk_window_get_pointer (gdkEvent.window, pointer_x, pointer_y, null);
      event.x = pointer_x [0];
      event.y = pointer_y [0];
    } else {
      int [] origin_x = new int [1], origin_y = new int [1];
      OS.gdk_window_get_origin (gdkEvent.window, origin_x, origin_y);  
      event.x = (int) (gdkEvent.x_root - origin_x [0]);
      event.y = (int) (gdkEvent.y_root - origin_y [0]);
    }
  } else {
    double [] root_x = new double [1], root_y = new double [1];
    OS.gdk_event_get_root_coords (eventPtr, root_x, root_y);  
    long /*int*/ window = OS.GTK_WIDGET_WINDOW (eventHandle ());
    int [] origin_x = new int [1], origin_y = new int [1];
    OS.gdk_window_get_origin (window, origin_x, origin_y);
    event.x = (int)(root_x [0] - origin_x [0]);
    event.y = (int)(root_y [0] - origin_y [0]);
  }
  int [] state = new int [1];
  OS.gdk_event_get_state (eventPtr, state);
  setInputState (event, state [0]);
  postEvent (type, event);
}

/**
 * Sets the receiver's background color to the color specified
 * by the argument, or to the default system color for the control
 * if the argument is null.
 *
 * @param color the new color (or null)
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_INVALID_ARGUMENT - if the argument has been disposed</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 setBackground (Color color) {
  checkWidget();
  GdkColor gdkColor = null;
  if (color != null) {
    if (color.isDisposed ()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
    gdkColor = color.handle;
  }
  boolean set = false;
  if (gdkColor == null) {
    long /*int*/ style = OS.gtk_widget_get_modifier_style (handle);
    set = (OS.gtk_rc_style_get_color_flags (style, OS.GTK_STATE_NORMAL) & OS.GTK_RC_BG) != 0;
  } else {
    GdkColor oldColor = getBackgroundColor ();
    set = oldColor.pixel != gdkColor.pixel;
  }
  if (set) setBackgroundColor (gdkColor);
}

void setBackgroundColor (long /*int*/ handle, GdkColor color) {
  int index = OS.GTK_STATE_NORMAL;
  long /*int*/ style = OS.gtk_widget_get_modifier_style (handle);
  long /*int*/ ptr = OS.gtk_rc_style_get_bg_pixmap_name (style, index);
  if (ptr != 0) OS.g_free (ptr);
  String name = color == null ? "<parent>" : "<none>";
  byte[] buffer = Converter.wcsToMbcs (null, name, true);
  ptr = OS.g_malloc (buffer.length);
  OS.memmove (ptr, buffer, buffer.length);
  OS.gtk_rc_style_set_bg_pixmap_name (style, index, ptr);
  OS.gtk_rc_style_set_bg (style, index, color);
  int flags = OS.gtk_rc_style_get_color_flags (style, index);
  flags = (color == null) ? flags & ~OS.GTK_RC_BG : flags | OS.GTK_RC_BG;
  OS.gtk_rc_style_set_color_flags (style, index, flags);
  OS.gtk_widget_modify_style (handle, style);
}
void setBackgroundColor (GdkColor color) {
  setBackgroundColor(handle, color);
}

/**
 * If the argument is <code>true</code>, causes the receiver to have
 * all mouse events delivered to it until the method is called with
 * <code>false</code> as the argument.
 *
 * @param capture <code>true</code> to capture the mouse, and <code>false</code> to release it
 *
 * @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 setCapture (boolean capture) {
  checkWidget();
  /* FIXME !!!!! */
  /*
  if (capture) {
    OS.gtk_widget_grab_focus (handle);
  } else {
    OS.gtk_widget_grab_default (handle);
  }
  */
}
/**
 * Sets the receiver's cursor to the cursor specified by the
 * argument, or to the default cursor for that kind of control
 * if the argument is null.
 * <p>
 * When the mouse pointer passes over a control its appearance
 * is changed to match the control's cursor.
 * </p>
 *
 * @param cursor the new cursor (or null)
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_INVALID_ARGUMENT - if the argument has been disposed</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 setCursor (Cursor cursor) {
  checkWidget();
  if (cursor != null && cursor.isDisposed ()) error (SWT.ERROR_INVALID_ARGUMENT);
  this.cursor = cursor;
  setCursor (cursor != null ? cursor.handle : 0);
}

void setCursor (long /*int*/ cursor) {
  long /*int*/ window = paintWindow ();
  if (window != 0) {
    OS.gdk_window_set_cursor (window, cursor);
    OS.gdk_flush ();
  }
}

/**
 * Enables the receiver if the argument is <code>true</code>,
 * and disables it otherwise. A disabled control is typically
 * not selectable from the user interface and draws with an
 * inactive or "grayed" look.
 *
 * @param enabled the new enabled state
 *
 * @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 setEnabled (boolean enabled) {
  checkWidget();
  if (((state & DISABLED) == 0) == enabled) return;
  Control control = null;
  boolean fixFocus = false;
  if (!enabled) {
    control = display.getFocusControl ();
    fixFocus = isFocusAncestor (control);
  }
  if (enabled) {
    state &= ~DISABLED;
  } else {
    state |= DISABLED;
  }
  enableWidget (enabled);
  if (enabled) {
    if (enableWindow != 0) {
      OS.gdk_window_set_user_data (enableWindow, 0);
      OS.gdk_window_destroy (enableWindow);
      enableWindow = 0;
    }
  } else {
    OS.gtk_widget_realize (handle);
    long /*int*/ parentHandle = parent.parentingHandle ();
    long /*int*/ window = OS.GTK_WIDGET_WINDOW (parentHandle);
    Rectangle rect = getBounds ();
    GdkWindowAttr attributes = new GdkWindowAttr ();
    attributes.x = rect.x;
    attributes.y = rect.y;
    attributes.width = rect.width;
    attributes.height = rect.height;
    attributes.event_mask = (0xFFFFFFFF & ~OS.ExposureMask);
    attributes.wclass = OS.GDK_INPUT_ONLY;
    attributes.window_type = OS.GDK_WINDOW_CHILD;
    enableWindow = OS.gdk_window_new (window, attributes, OS.GDK_WA_X | OS.GDK_WA_Y);
    if (enableWindow != 0) {
      long /*int*/ topHandle = topHandle ();
      OS.gdk_window_set_user_data (enableWindow, parentHandle);
      if (!OS.GDK_WINDOWING_X11 ()) {
        OS.gdk_window_raise (enableWindow);
      } else {
        long /*int*/ topWindow = OS.GTK_WIDGET_WINDOW (topHandle);      
        long /*int*/ xDisplay = OS.gdk_x11_drawable_get_xdisplay (topWindow);
        long /*int*/ xWindow = OS.gdk_x11_drawable_get_xid (enableWindow);
        int xScreen = OS.XDefaultScreen (xDisplay);
        int flags = OS.CWStackMode | OS.CWSibling;      
        XWindowChanges changes = new XWindowChanges ();
        changes.sibling = OS.gdk_x11_drawable_get_xid (topWindow);
        changes.stack_mode = OS.Above;
        OS.XReconfigureWMWindow (xDisplay, xWindow, xScreen, flags, changes);
      }
      if (OS.GTK_WIDGET_VISIBLE (topHandle)) OS.gdk_window_show (enableWindow);
    }
  }
  if (fixFocus) fixFocus (control);
}

/**
 * Causes the receiver to have the <em>keyboard focus</em>, 
 * such that all keyboard events will be delivered to it.  Focus
 * reassignment will respect applicable platform constraints.
 *
 * @return <code>true</code> if the control got focus, and <code>false</code> if it was unable to.
 *
 * @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 #forceFocus
 */
public boolean setFocus () {
  checkWidget();
  if ((style & SWT.NO_FOCUS) != 0) return false;
  return forceFocus ();
}

/**
 * Sets the font that the receiver will use to paint textual information
 * to the font specified by the argument, or to the default font for that
 * kind of control if the argument is null.
 *
 * @param font the new font (or null)
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_INVALID_ARGUMENT - if the argument has been disposed</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 setFont (Font font) {
  checkWidget();
  this.font = font;
  long /*int*/ fontDesc;
  if (font == null) {
    fontDesc = defaultFont ();
  } else {
    if (font.isDisposed ()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
    fontDesc = font.handle;
  }
  setFontDescription (fontDesc);
}
  
void setFontDescription (long /*int*/ font) {
  OS.gtk_widget_modify_font (handle, font);
}

/**
 * Sets the receiver's foreground color to the color specified
 * by the argument, or to the default system color for the control
 * if the argument is null.
 *
 * @param color the new color (or null)
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_INVALID_ARGUMENT - if the argument has been disposed</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 setForeground (Color color) {
  checkWidget();
  GdkColor gdkColor = null;
  if (color != null) {
    if (color.isDisposed ()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
    gdkColor = color.handle;
  }
  boolean set = false;
  if (gdkColor == null) {
    long /*int*/ style = OS.gtk_widget_get_modifier_style (handle);
    set = (OS.gtk_rc_style_get_color_flags (style, OS.GTK_STATE_NORMAL) & OS.GTK_RC_FG) != 0;
  } else {
    GdkColor oldColor = getForegroundColor ();
    set = oldColor.pixel != gdkColor.pixel;
  }
  if (set) setForegroundColor (gdkColor);
}

void setForegroundColor (GdkColor color) {
  OS.gtk_widget_modify_fg (handle, OS.GTK_STATE_NORMAL, color);
}

void setInitialSize () {
  resizeHandle (1, 1);
  /*
  * Force the container to allocate the size of its children.
  */
  long /*int*/ parentHandle = parent.parentingHandle ();
  OS.gtk_container_resize_children (parentHandle);
}

/**
 * Sets the receiver's pop up menu to the argument.
 * All controls may optionally have a pop up
 * menu that is displayed when the user requests one for
 * the control. The sequence of key strokes, button presses
 * and/or button releases that are used to request a pop up
 * menu is platform specific.
 *
 * @param menu the new pop up menu
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_MENU_NOT_POP_UP - the menu is not a pop up menu</li>
 *    <li>ERROR_INVALID_PARENT - if the menu is not in the same widget tree</li>
 *    <li>ERROR_INVALID_ARGUMENT - if the menu has been disposed</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 setMenu (Menu menu) {
  checkWidget();
  if (menu != null) {
    if ((menu.style & SWT.POP_UP) == 0) {
      error (SWT.ERROR_MENU_NOT_POP_UP);
    }
    if (menu.parent != menuShell ()) {
      error (SWT.ERROR_INVALID_PARENT);
    }
  }
  this.menu = menu;
}

/**
 * Changes the parent of the widget to be the one provided if
 * the underlying operating system supports this feature.
 * Answers <code>true</code> if the parent is successfully changed.
 *
 * @param parent the new parent for the control.
 * @return <code>true</code> if the parent is changed and <code>false</code> otherwise.
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_INVALID_ARGUMENT - if the argument has been disposed</li> 
 * </ul>
 * @exception SWTError <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS when called from the wrong thread</li>
 *    <li>ERROR_WIDGET_DISPOSED when the widget has been disposed</li>
 *  </ul>
 */
public boolean setParent (Composite parent) {
  checkWidget ();
  if (parent == null) SWT.error (SWT.ERROR_NULL_ARGUMENT);
  if (parent.isDisposed()) SWT.error (SWT.ERROR_INVALID_ARGUMENT);
  if (this.parent == parent) return true;
  if (!isReparentable ()) return false;
  releaseChild ();
  Shell newShell = parent.getShell (), oldShell = getShell ();
  Decorations newDecorations = parent.menuShell (), oldDecorations = menuShell ();
  Menu [] menus = oldShell.findMenus (this);
  if (oldShell != newShell || oldDecorations != newDecorations) {
    fixChildren (newShell, oldShell, newDecorations, oldDecorations, menus);
    newDecorations.fixAccelGroup ();
    oldDecorations.fixAccelGroup ();
  }
  long /*int*/ topHandle = topHandle ();
  long /*int*/ newParent = parent.parentingHandle();
  int x = OS.GTK_WIDGET_X (topHandle);
  int y = OS.GTK_WIDGET_Y (topHandle);
  OS.gtk_widget_reparent (topHandle, newParent);
  OS.gtk_fixed_move (newParent, topHandle, x, y);
  this.parent = parent;
  setZOrder (null, false);
  return true;
}

boolean setRadioSelection (boolean value) {
  return false;
}

/**
 * If the argument is <code>false</code>, causes subsequent drawing
 * operations in the receiver to be ignored. No drawing of any kind
 * can occur in the receiver until the flag is set to true.
 * Graphics operations that occurred while the flag was
 * <code>false</code> are lost. When the flag is set to <code>true</code>,
 * the entire widget is marked as needing to be redrawn.
 * <p>
 * Note: This operation is a hint and may not be supported on some
 * platforms or for some widgets.
 * </p>
 *
 * @param redraw the new redraw state
 *
 * @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 #redraw
 * @see #update
 */
public void setRedraw (boolean redraw) {
  checkWidget();
  if (redraw) {
    if (--drawCount == 0) {
      if (redrawWindow != 0) {
        long /*int*/ window = paintWindow ();
        OS.gdk_window_destroy (redrawWindow);
        OS.gdk_window_set_events (window, OS.gtk_widget_get_events (paintHandle ()));
        redrawWindow = 0;
      }
    }
  } else {
    if (drawCount++ == 0) {
      if ((OS.GTK_WIDGET_FLAGS (handle) & OS.GTK_REALIZED) != 0) {
        long /*int*/ window = paintWindow ();
        Rectangle rect = getBounds ();
        GdkWindowAttr attributes = new GdkWindowAttr ();
        attributes.width = rect.width;
        attributes.height = rect.height;
        attributes.event_mask = OS.GDK_EXPOSURE_MASK;
        attributes.window_type = OS.GDK_WINDOW_CHILD;
        redrawWindow = OS.gdk_window_new (window, attributes, 0);
        if (redrawWindow != 0) {
          int mouseMask = OS.GDK_BUTTON_PRESS_MASK | OS.GDK_BUTTON_RELEASE_MASK |
            OS.GDK_ENTER_NOTIFY_MASK | OS.GDK_LEAVE_NOTIFY_MASK |
            OS.GDK_POINTER_MOTION_MASK | OS.GDK_POINTER_MOTION_HINT_MASK |
            OS.GDK_BUTTON_MOTION_MASK | OS.GDK_BUTTON1_MOTION_MASK | 
            OS.GDK_BUTTON2_MOTION_MASK | OS.GDK_BUTTON3_MOTION_MASK;
          OS.gdk_window_set_events (window, OS.gdk_window_get_events (window) & ~mouseMask);
          OS.gdk_window_set_back_pixmap (redrawWindow, 0, false);
          OS.gdk_window_raise (redrawWindow);
          OS.gdk_window_show (redrawWindow);
        }
      }
    }
  }
}

boolean setTabGroupFocus (boolean next) {
  return setTabItemFocus (next);
}
boolean setTabItemFocus (boolean next) {
  if (!isShowing ()) return false;
  return forceFocus ();
}

/**
 * Sets the receiver's tool tip text to the argument, which
 * may be null indicating that no tool tip text should be shown.
 *
 * @param string the new tool tip text (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 void setToolTipText (String string) {
  checkWidget();
  Shell shell = _getShell ();
  shell.setToolTipText (eventHandle (), toolTipText = string);
}

/**
 * Marks the receiver as visible if the argument is <code>true</code>,
 * and marks it invisible otherwise. 
 * <p>
 * If one of the receiver's ancestors is not visible or some
 * other condition makes the receiver not visible, marking
 * it visible may not actually cause it to be displayed.
 * </p>
 *
 * @param visible the new visibility state
 *
 * @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 setVisible (boolean visible) {
  checkWidget();
  long /*int*/ topHandle = topHandle();
  if ((OS.GTK_WIDGET_VISIBLE (topHandle) == visible)) return;
  if (visible) {
    /*
    * It is possible (but unlikely), that application
    * code could have disposed the widget in the show
    * event.  If this happens, just return.
    */
    sendEvent (SWT.Show);
    if (isDisposed ()) return;
    if (enableWindow != 0) OS.gdk_window_show (enableWindow);
    OS.gtk_widget_show (topHandle);
  } else {
    /*
    * Bug in GTK.  Invoking gtk_widget_hide() on a widget that has
    * focus causes a focus_out_event to be sent. If the client disposes
    * the widget inside the event, GTK GP's.  The fix is to reassign focus
    * before hiding the widget.
    * 
    * NOTE: In order to stop the same widget from taking focus,
    * temporarily clear and set the GTK_VISIBLE flag.
    */    
    Control control = null;
    boolean fixFocus = false;
    if (!visible) {
      control = display.getFocusControl ();
      fixFocus = isFocusAncestor (control);
    }
    if (fixFocus) {
      int flags = OS.GTK_WIDGET_FLAGS (topHandle);
      OS.GTK_WIDGET_UNSET_FLAGS (topHandle, OS.GTK_VISIBLE);
      fixFocus (control);
      if (isDisposed ()) return;
      if ((flags & OS.GTK_VISIBLE) != 0) {
        OS.GTK_WIDGET_SET_FLAGS (topHandle, OS.GTK_VISIBLE);
      }
    }
    OS.gtk_widget_hide (topHandle);
    if (enableWindow != 0) OS.gdk_window_hide (enableWindow);
    sendEvent (SWT.Hide);
  }
}

void setZOrder (Control sibling, boolean above) {
   setZOrder (sibling, above, true);
}

void setZOrder (Control sibling, boolean above, boolean fixChildren) {
  long /*int*/ topHandle = topHandle ();
  long /*int*/ siblingHandle = sibling != null ? sibling.topHandle () : 0;
  long /*int*/ window = OS.GTK_WIDGET_WINDOW (topHandle);
  if (window != 0) {
    long /*int*/ siblingWindow = 0;
    if (sibling != null) {
      if (above && sibling.enableWindow != 0) {
        siblingWindow = enableWindow;
      } else {
        siblingWindow = OS.GTK_WIDGET_WINDOW (siblingHandle);
      }
    }
    long /*int*/ redrawWindow = fixChildren ? parent.redrawWindow : 0;
    if (!OS.GDK_WINDOWING_X11 () || (siblingWindow == 0 && redrawWindow == 0)) {
      if (above) {
        OS.gdk_window_raise (window);
        if (redrawWindow != 0) OS.gdk_window_raise (redrawWindow);
        if (enableWindow != 0) OS.gdk_window_raise (enableWindow);
      } else {
        if (enableWindow != 0) OS.gdk_window_lower (enableWindow);
        OS.gdk_window_lower (window);
      }
    } else {
      XWindowChanges changes = new XWindowChanges ();
      changes.sibling = OS.gdk_x11_drawable_get_xid (siblingWindow != 0 ? siblingWindow : redrawWindow);
      changes.stack_mode = above ? OS.Above : OS.Below;
      if (redrawWindow != 0 && siblingWindow == 0) changes.stack_mode = OS.Below;
      long /*int*/ xDisplay = OS.gdk_x11_drawable_get_xdisplay (window);
      long /*int*/ xWindow = OS.gdk_x11_drawable_get_xid (window);
      int xScreen = OS.XDefaultScreen (xDisplay);
      int flags = OS.CWStackMode | OS.CWSibling;
      /*
      * Feature in X. If the receiver is a top level, XConfigureWindow ()
      * will fail (with a BadMatch error) for top level shells because top
      * level shells are reparented by the window manager and do not share
      * the same X window parent.  This is the correct behavior but it is
      * unexpected.  The fix is to use XReconfigureWMWindow () instead.
      * When the receiver is not a top level shell, XReconfigureWMWindow ()
      * behaves the same as XConfigureWindow ().
      */
      OS.XReconfigureWMWindow (xDisplay, xWindow, xScreen, flags, changes);      
      if (enableWindow != 0) {
        changes.sibling = OS.gdk_x11_drawable_get_xid (window);
        changes.stack_mode = OS.Above;
        xWindow = OS.gdk_x11_drawable_get_xid (enableWindow);
        OS.XReconfigureWMWindow (xDisplay, xWindow, xScreen, flags, changes);
      }
    }
  }
  if (fixChildren) {
    if (above) {
      parent.moveAbove (topHandle, siblingHandle);
    } else {
      parent.moveBelow (topHandle, siblingHandle);
    }
  }
  /*
  * Make sure that the parent handle is on the bottom of the stack
  * when the parent children are siblings of the parent handle.
  */
  if (!above && fixChildren && parent.parentingHandle () == parent.fixedHandle) {
    window = OS.GTK_WIDGET_WINDOW (parent.handle);
    if (window != 0) OS.gdk_window_lower (window);
  }
}

boolean showMenu (int x, int y) {
  Event event = new Event ();
  event.x = x;
  event.y = y;
  sendEvent (SWT.MenuDetect, event);
  if (event.doit) {
    if (menu != null && !menu.isDisposed ()) {
      menu.createIMMenu (imHandle());
      if (event.x != x || event.y != y) {
        menu.setLocation (event.x, event.y);
      }
      menu.setVisible (true);
      return true;
    }
  }
  return false;
}

void sort (int [] items) {
  /* Shell Sort from K&R, pg 108 */
  int length = items.length;
  for (int gap=length/2; gap>0; gap/=2) {
    for (int i=gap; i<length; i++) {
      for (int j=i-gap; j>=0; j-=gap) {
           if (items [j] <= items [j + gap]) {
          int swap = items [j];
          items [j] = items [j + gap];
          items [j + gap] = swap;
           }
        }
      }
  }
}

/**
 * Based on the argument, perform one of the expected platform
 * traversal action. The argument should be one of the constants:
 * <code>SWT.TRAVERSE_ESCAPE</code>, <code>SWT.TRAVERSE_RETURN</code>, 
 * <code>SWT.TRAVERSE_TAB_NEXT</code>, <code>SWT.TRAVERSE_TAB_PREVIOUS</code>, 
 * <code>SWT.TRAVERSE_ARROW_NEXT</code> and <code>SWT.TRAVERSE_ARROW_PREVIOUS</code>.
 *
 * @param traversal the type of traversal
 * @return true if the traversal succeeded
 *
 * @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 traverse (int traversal) {
  checkWidget ();
  Event event = new Event ();
  event.doit = true;
  event.detail = traversal;
  return traverse (event);
}

boolean translateMnemonic (Event event, Control control) {
  if (control == this) return false;
  if (!isVisible () || !isEnabled ()) return false;
  event.doit = this == display.mnemonicControl || mnemonicMatch (event.character);
  return traverse (event);
}

boolean translateMnemonic (int keyval, GdkEventKey gdkEvent) {
  int key = OS.gdk_keyval_to_unicode (keyval);
  if (key < 0x20) return false;
  if (gdkEvent.state == 0) {
    int code = traversalCode (keyval, gdkEvent);
    if ((code & SWT.TRAVERSE_MNEMONIC) == 0) return false;
  } else {
    Shell shell = _getShell ();
    int mask = OS.GDK_CONTROL_MASK | OS.GDK_SHIFT_MASK | OS.GDK_MOD1_MASK;
    if ((gdkEvent.state & mask) != OS.gtk_window_get_mnemonic_modifier (shell.shellHandle)) return false;
  }
  Decorations shell = menuShell ();
  if (shell.isVisible () && shell.isEnabled ()) {
    Event event = new Event ();
    event.detail = SWT.TRAVERSE_MNEMONIC;
    if (setKeyState (event, gdkEvent)) {
      return translateMnemonic (event, null) || shell.translateMnemonic (event, this);
    }
  }
  return false;
}

boolean translateTraversal (GdkEventKey keyEvent) {
  int detail = SWT.TRAVERSE_NONE;
  int key = keyEvent.keyval;
  int code = traversalCode (key, keyEvent);
  boolean all = false;
  switch (key) {
    case OS.GDK_Escape: {
      all = true;
      detail = SWT.TRAVERSE_ESCAPE;
      break;
    }
    case OS.GDK_KP_Enter:
    case OS.GDK_Return: {
      all = true;
      detail = SWT.TRAVERSE_RETURN;
      break;
    }
    case OS.GDK_ISO_Left_Tab: 
    case OS.GDK_Tab: {
      boolean next = (keyEvent.state & OS.GDK_SHIFT_MASK) == 0;
      detail = next ? SWT.TRAVERSE_TAB_NEXT : SWT.TRAVERSE_TAB_PREVIOUS;
      break;
    }
    case OS.GDK_Up:
    case OS.GDK_Left: 
    case OS.GDK_Down:
    case OS.GDK_Right: {
      boolean next = key == OS.GDK_Down || key == OS.GDK_Right;
      detail = next ? SWT.TRAVERSE_ARROW_NEXT : SWT.TRAVERSE_ARROW_PREVIOUS;
      break;
    }
    case OS.GDK_Page_Up:
    case OS.GDK_Page_Down: {
      all = true;
      if ((keyEvent.state & OS.GDK_CONTROL_MASK) == 0) return false;
      detail = key == OS.GDK_Page_Down ? SWT.TRAVERSE_PAGE_NEXT : SWT.TRAVERSE_PAGE_PREVIOUS;
      break;
    }
    default:
      return false;
  }
  Event event = new Event ();
  event.doit = (code & detail) != 0;
  event.detail = detail;
  event.time = keyEvent.time;
  if (!setKeyState (event, keyEvent)) return false;
  Shell shell = getShell ();
  Control control = this;
  do {
    if (control.traverse (event)) return true;
    if (!event.doit && control.hooks (SWT.Traverse)) return false;
    if (control == shell) return false;
    control = control.parent;
  } while (all && control != null);
  return false;
}

int traversalCode (int key, GdkEventKey event) {
  int code = SWT.TRAVERSE_RETURN | SWT.TRAVERSE_TAB_NEXT |  SWT.TRAVERSE_TAB_PREVIOUS | SWT.TRAVERSE_PAGE_NEXT | SWT.TRAVERSE_PAGE_PREVIOUS;
  Shell shell = getShell ();
  if (shell.parent != null) code |= SWT.TRAVERSE_ESCAPE;
  return code;
}

boolean traverse (Event event) {
  /*
  * It is possible (but unlikely), that application
  * code could have disposed the widget in the traverse
  * event.  If this happens, return true to stop further
  * event processing.
  */  
  sendEvent (SWT.Traverse, event);
  if (isDisposed ()) return true;
  if (!event.doit) return false;
  switch (event.detail) {
    case SWT.TRAVERSE_NONE:      return true;
    case SWT.TRAVERSE_ESCAPE:      return traverseEscape ();
    case SWT.TRAVERSE_RETURN:      return traverseReturn ();
    case SWT.TRAVERSE_TAB_NEXT:    return traverseGroup (true);
    case SWT.TRAVERSE_TAB_PREVIOUS:  return traverseGroup (false);
    case SWT.TRAVERSE_ARROW_NEXT:    return traverseItem (true);
    case SWT.TRAVERSE_ARROW_PREVIOUS:  return traverseItem (false);
    case SWT.TRAVERSE_MNEMONIC:    return traverseMnemonic (event.character);  
    case SWT.TRAVERSE_PAGE_NEXT:    return traversePage (true);
    case SWT.TRAVERSE_PAGE_PREVIOUS:  return traversePage (false);
  }
  return false;
}

boolean traverseEscape () {
  return false;
}

boolean traverseGroup (boolean next) {
  Control root = computeTabRoot ();
  Control group = computeTabGroup ();
  Control [] list = root.computeTabList ();
  int length = list.length;
  int index = 0;
  while (index < length) {
    if (list [index] == group) break;
    index++;
  }
  /*
  * It is possible (but unlikely), that application
  * code could have disposed the widget in focus in
  * or out events.  Ensure that a disposed widget is
  * not accessed.
  */
  if (index == length) return false;
  int start = index, offset = (next) ? 1 : -1;
  while ((index = ((index + offset + length) % length)) != start) {
    Control control = list [index];
    if (!control.isDisposed () && control.setTabGroupFocus (next)) {
      return true;
    }
  }
  if (group.isDisposed ()) return false;
  return group.setTabGroupFocus (next);
}

boolean traverseItem (boolean next) {
  Control [] children = parent._getChildren ();
  int length = children.length;
  int index = 0;
  while (index < length) {
    if (children [index] == this) break;
    index++;
  }
  /*
  * It is possible (but unlikely), that application
  * code could have disposed the widget in focus in
  * or out events.  Ensure that a disposed widget is
  * not accessed.
  */
  if (index == length) return false;
  int start = index, offset = (next) ? 1 : -1;
  while ((index = (index + offset + length) % length) != start) {
    Control child = children [index];
    if (!child.isDisposed () && child.isTabItem ()) {
      if (child.setTabItemFocus (next)) return true;
    }
  }
  return false;
}

boolean traverseReturn () {
  return false;
}

boolean traversePage (boolean next) {
  return false;
}

boolean traverseMnemonic (char key) {
  return mnemonicHit (key);
}

/**
 * Forces all outstanding paint requests for the widget
 * to be processed before this method returns.
 *
 * @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 #redraw
 * @see PaintListener
 * @see SWT#Paint
 */
public void update () {
  checkWidget ();
  update (false);
}

void update (boolean all) {
//  checkWidget();
  if ((OS.GTK_WIDGET_FLAGS (handle) & OS.GTK_REALIZED) == 0) return;
  long /*int*/ window = paintWindow ();
  display.flushExposes (window, all);
  OS.gdk_window_process_updates (window, all);
}
}