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 = <