bundles/org.eclipse.swt/Eclipse SWT/gtk1x/org/eclipse/swt/widgets/MenuItem.java

package org.eclipse.swt.widgets;

/*
 * Copyright (c) 2000, 2002 IBM Corp.  All rights reserved.
 * This file is 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
 */

import org.eclipse.swt.*;
import org.eclipse.swt.internal.*;
import org.eclipse.swt.internal.gtk.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.events.*;

/**
 * Instances of this class represent a selectable user interface object
 * that issues notification when pressed and released. 
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>CHECK, CASCADE, PUSH, RADIO, SEPARATOR</dd>
 * <dt><b>Events:</b></dt>
 * <dd>Arm, Help, Selection</dd>
 * </dl>
 * <p>
 * Note: Only one of the styles CHECK, CASCADE, PUSH, RADIO, and SEPARATOR 
 * may be specified.
 * </p><p>
 * IMPORTANT: This class is <em>not</em> intended to be subclassed.
 * </p>
 */

public class MenuItem extends Item {
	Menu parent, menu;
	int accelerator;
	
/**
 * Constructs a new instance of this class given its parent
 * (which must be a <code>Menu</code>) and a style value
 * describing its behavior and appearance. The item is added
 * to the end of the items maintained by its parent.
 * <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
 * for all SWT widget classes should include a comment which
 * describes the style constants which are applicable to the class.
 * </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
 * @see Widget#checkSubclass
 * @see Widget#getStyle
 */
public MenuItem (Menu parent, int style) {
	super (parent, checkStyle (style));
	this.parent = parent;
	createWidget (parent.getItemCount ());
}
/**
 * Constructs a new instance of this class given its parent
 * (which must be a <code>Menu</code>), a style value
 * describing its behavior and appearance, and the index
 * at which to place it in the items maintained by its parent.
 * <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
 * for all SWT widget classes should include a comment which
 * describes the style constants which are applicable to the class.
 * </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
 * @param index the index to store the receiver in its parent
 *
 * @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
 * @see Widget#checkSubclass
 * @see Widget#getStyle
 */
public MenuItem (Menu parent, int style, int index) {
	super (parent, checkStyle (style));
	this.parent = parent;
	int count = parent.getItemCount ();
	if (!(0 <= index && index <= count)) {
		error (SWT.ERROR_ITEM_NOT_ADDED);
	}
	createWidget (index);
}
void addAccelerator (int accel_group) {
	if (accel_group == 0) return;
	if (accelerator == 0) return;
	byte [] activate = Converter.wcsToMbcs (null, "activate", true);
	int mask = 0;
	if ((accelerator & SWT.CONTROL) != 0) mask |= OS.GDK_CONTROL_MASK;
	if ((accelerator & SWT.ALT) != 0) mask |= OS.GDK_MOD1_MASK;
	if ((accelerator & SWT.SHIFT) != 0) mask |= OS.GDK_SHIFT_MASK;
	int keysym = accelerator & ~(SWT.ALT | SWT.SHIFT | SWT.CTRL);
	int newKey = Display.untranslateKey (keysym);
	if (newKey != 0) {
		keysym = newKey;
	} else {
		keysym = wcsToMbcs ((char) keysym);
	}
	OS.gtk_widget_add_accelerator (handle, activate, accel_group, keysym, mask, OS.GTK_ACCEL_VISIBLE);
}
/**
 * Adds the listener to the collection of listeners who will
 * be notified when the arm events are generated for the control, by sending
 * it one of the messages defined in the <code>ArmListener</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 ArmListener
 * @see #removeArmListener
 */
public void addArmListener (ArmListener listener) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	TypedListener typedListener = new TypedListener (listener);
	addListener (SWT.Arm, typedListener);
}

/**
 * Adds the listener to the collection of listeners who will
 * be notified when the 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) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	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 the control is selected, by sending
 * it one of the messages defined in the <code>SelectionListener</code>
 * interface.
 * <p>
 * When <code>widgetSelected</code> is called, the stateMask field of the event object is valid.
 * <code>widgetDefaultSelected</code> is not called.
 * </p>
 *
 * @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 SelectionListener
 * @see #removeSelectionListener
 * @see SelectionEvent
 */
public void addSelectionListener (SelectionListener listener) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	TypedListener typedListener = new TypedListener(listener);
	addListener (SWT.Selection,typedListener);
	addListener (SWT.DefaultSelection,typedListener);
}
static int checkStyle (int style) {
	return checkBits (style, SWT.PUSH, SWT.CHECK, SWT.RADIO, SWT.SEPARATOR, SWT.CASCADE, 0);
}
void createHandle (int index) {
	state |= HANDLE;
	byte [] buffer = new byte [1];
	int bits = SWT.CHECK | SWT.RADIO | SWT.PUSH | SWT.SEPARATOR;
	switch (style & bits) {
		case SWT.SEPARATOR:
			handle = OS.gtk_menu_item_new ();
			break;
		case SWT.RADIO:
//			handle = OS.gtk_radio_menu_item_new_with_label (0, buffer);
//			break;
		case SWT.CHECK:
			handle = OS.gtk_check_menu_item_new_with_label (buffer);
			break;
		case SWT.PUSH:
		default:
			handle = OS.gtk_menu_item_new_with_label (buffer);
			break;
	}
	if (handle == 0) error (SWT.ERROR_NO_HANDLES);
	if ((style & (SWT.CHECK | SWT.RADIO)) != 0) {
		OS.gtk_check_menu_item_set_show_toggle (handle, true);
	}
	if ((parent.style & SWT.BAR) != 0) {
		OS.gtk_menu_bar_insert (parent.handle, handle, index);
	} else {
		OS.gtk_menu_insert (parent.handle, handle, index);
	}
	OS.gtk_widget_show (handle);
}
/**
 * Return the widget accelerator.  An accelerator is the bit-wise
 * OR of zero or more modifier masks and a key. Examples:
 * <code>SWT.CONTROL | SWT.SHIFT | 'T', SWT.ALT | SWT.F2</code>.
 *
 * @return the accelerator
 *
 * </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 int getAccelerator () {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	return accelerator;
}
public Display getDisplay () {
	Menu parent = this.parent;
	if (parent == null) error (SWT.ERROR_WIDGET_DISPOSED);
	return parent.getDisplay ();
}
/**
 * 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>
 */
public boolean getEnabled () {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	GtkWidget widget = new GtkWidget ();
	OS.memmove (widget, handle, GtkWidget.sizeof);
	return (widget.flags & OS.GTK_SENSITIVE) != 0;     
}
/**
 * Returns the receiver's cascade menu if it has one or null
 * if it does not. Only <code>CASCADE</code> menu items can have
 * a pull down menu. The sequence of key strokes, button presses 
 * and/or button releases that are used to request a pull down
 * 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 () {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	return menu;
}
/**
 * Returns the receiver's parent, which must be a <code>Menu</code>.
 *
 * @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 Menu getParent () {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	return parent;
}
/**
 * Returns <code>true</code> if the receiver is selected,
 * and false otherwise.
 * <p>
 * When the receiver is of type <code>CHECK</code> or <code>RADIO</code>,
 * it is selected when it is checked.
 *
 * @return the selection 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 getSelection () {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	if ((style & (SWT.CHECK | SWT.RADIO)) == 0) return false;
	GtkCheckMenuItem menuItem = new GtkCheckMenuItem ();
	OS.memmove (menuItem, handle, GtkCheckMenuItem.sizeof);
	return menuItem.active != 0;
}
void hookEvents () {
	super.hookEvents ();
	Display display = getDisplay ();
	int windowProc2 = display.windowProc2;
	byte [] activate_event = Converter.wcsToMbcs (null, "activate", true);
	OS.gtk_signal_connect (handle, activate_event, windowProc2, SWT.Selection);
}
/**
 * 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>
 */
public boolean isEnabled () {
	return getEnabled ();
}
int processSelection (int int0, int int1, int int2) {
	postEvent (SWT.Selection);
	return 0;
}
void releaseChild () {
	super.releaseChild ();
	if (menu != null) menu.dispose ();
	menu = null;
}
void releaseWidget () {
	if (menu != null) {
		menu.releaseWidget ();
		menu.releaseHandle ();
	}
	menu = null;
	super.releaseWidget ();
	int accel_group = parent.getShell ().accelGroup;
	removeAccelerator (accel_group);
	accelerator = 0;
	parent = null;
}
void removeAccelerator (int accel_group) {
	if (accel_group == 0) return;
	if (accelerator == 0) return;
	int mask = 0;
	if ((accelerator & SWT.CONTROL) != 0) mask |= OS.GDK_CONTROL_MASK;
	if ((accelerator & SWT.ALT) != 0) mask |= OS.GDK_MOD1_MASK;
	if ((accelerator & SWT.SHIFT) != 0) mask |= OS.GDK_SHIFT_MASK;
	int keysym = accelerator & ~(SWT.ALT | SWT.SHIFT | SWT.CTRL);
	int newKey = Display.untranslateKey (keysym);
	if (newKey != 0) {
		keysym = newKey;
	} else {
		keysym = wcsToMbcs ((char) keysym);
	}
	OS.gtk_widget_remove_accelerator (handle, accel_group, keysym, mask);
	accelerator = 0;
}
/**
 * Removes the listener from the collection of listeners who will
 * be notified when the arm 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 ArmListener
 * @see #addArmListener
 */
public void removeArmListener (ArmListener listener) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (eventTable == null) return;
	eventTable.unhook (SWT.Arm, 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) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	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 the control is selected.
 *
 * @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 SelectionListener
 * @see #addSelectionListener
 */
public void removeSelectionListener (SelectionListener listener) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (eventTable == null) return;
	eventTable.unhook (SWT.Selection, listener);
	eventTable.unhook (SWT.DefaultSelection,listener);	
}
/**
 * Sets the widget accelerator.  An accelerator is the bit-wise
 * OR of zero or more modifier masks and a key. Examples:
 * <code>SWT.CONTROL | SWT.SHIFT | 'T', SWT.ALT | SWT.F2</code>.
 *
 * @param accelerator an integer that is the bit-wise OR of masks and a key
 *
 * </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 setAccelerator (int accelerator) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	int accel_group = parent.getShell ().accelGroup;
	if (accelerator != 0) removeAccelerator (accel_group);
	this.accelerator = accelerator;
	if (accelerator != 0) addAccelerator (accel_group);
}
/**
 * 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) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	OS.gtk_widget_set_sensitive (handle, enabled);
}



/**
 * Sets the receiver's pull down menu to the argument.
 * Only <code>CASCADE</code> menu items can have a
 * pull down menu. The sequence of key strokes, button presses
 * and/or button releases that are used to request a pull down
 * menu is platform specific.
 *
 * @param menu the new pull down menu
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_MENU_NOT_DROP_DOWN - if the menu is not a drop down menu</li>
 *    <li>ERROR_MENUITEM_NOT_CASCADE - if the menu item is not a <code>CASCADE</code></li>
 *    <li>ERROR_INVALID_ARGUMENT - if the menu has been disposed</li>
 *    <li>ERROR_INVALID_PARENT - if the menu is not in the same widget tree</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 ();

	/* Check to make sure the new menu is valid */
	if ((style & SWT.CASCADE) == 0) {
		error (SWT.ERROR_MENUITEM_NOT_CASCADE);
	}
	if (menu != null) {
		if ((menu.style & SWT.DROP_DOWN) == 0) {
			error (SWT.ERROR_MENU_NOT_DROP_DOWN);
		}
		if (menu.parent != parent.parent) {
			error (SWT.ERROR_INVALID_PARENT);
		}
	}

	/* Assign the new menu */
	Menu oldMenu = this.menu;
	if (oldMenu == menu) return;
	if (oldMenu != null) {
		oldMenu.cascade = null;
		/*
		* Add a reference to the menu we are about
		* to replace or GTK will destroy it.
		*/
		OS.gtk_object_ref (oldMenu.handle);
		OS.gtk_menu_item_remove_submenu (handle);
	}
	if ((this.menu = menu) != null) {
		menu.cascade = this;
		OS.gtk_menu_item_set_submenu (handle, menu.handle);
	}

	
}
/**
 * Sets the selection state of the receiver.
 * <p>
 * When the receiver is of type <code>CHECK</code> or <code>RADIO</code>,
 * it is selected when it is checked.
 *
 * @param selected the new selection 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 setSelection (boolean selected) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	if ((style & (SWT.CHECK | SWT.RADIO)) == 0) return;
	OS.gtk_signal_handler_block_by_data (handle, SWT.Selection);
	OS.gtk_check_menu_item_set_active (handle, selected);
	OS.gtk_signal_handler_unblock_by_data (handle, SWT.Selection);
}
public void setText (String string) {
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED);
	if (string == null) error (SWT.ERROR_NULL_ARGUMENT);
	if ((style & SWT.SEPARATOR) != 0) return;
	text = string;
	if ((style & SWT.ARROW) != 0) return;
	int length = string.length ();
	int index = string.indexOf('\t');
	if (index != -1) length = index;
	char [] text = new char [length + 1];
	char [] pattern = new char [length + 1];
	string.getChars (0, length, text, 0);
	int i = 0, j = 0;
	while (i < length) {
		pattern [j] = ' ';
		if (text [i] == '&') {
			i++;
			if (i < length && text [i] != '&') {
				pattern [j] = '_';
			}
		}
		text [j++] = text [i++];
	}
	while (j < i) {
		text [j] = pattern [j] = '\0';
		j++;
	}
	int list = OS.gtk_container_children (handle);
	int label = OS.g_list_nth_data (list, 0);
	byte [] buffer1 = Converter.wcsToMbcs (null, text);
	OS.gtk_label_set_text (label, buffer1);
	byte [] buffer2 = Converter.wcsToMbcs (null, pattern);
	OS.gtk_label_set_pattern (label, buffer2);
}
}