bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/ToolBar.java

/*******************************************************************************
 * Copyright (c) 2000, 2018 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.widgets;


import java.util.*;

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

/**
 * Instances of this class support the layout of selectable
 * tool bar items.
 * <p>
 * The item children that may be added to instances of this class
 * must be of type <code>ToolItem</code>.
 * </p><p>
 * Note that although this class is a subclass of <code>Composite</code>,
 * it does not make sense to add <code>Control</code> children to it,
 * or set a layout on it.
 * </p>
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>FLAT, WRAP, RIGHT, HORIZONTAL, VERTICAL, SHADOW_OUT</dd>
 * <dt><b>Events:</b></dt>
 * <dd>(none)</dd>
 * </dl>
 * <p>
 * Note: Only one of the styles HORIZONTAL and VERTICAL may be specified.
 * </p><p>
 * IMPORTANT: This class is <em>not</em> intended to be subclassed.
 * </p>
 *
 * @see <a href="http://www.eclipse.org/swt/snippets/#toolbar">ToolBar, ToolItem snippets</a>
 * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: ControlExample</a>
 * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
 * @noextend This class is not intended to be subclassed by clients.
 */
public class ToolBar extends Composite {
	ToolItem currentFocusItem;
	ToolItem [] tabItemList;
	ImageList imageList;
	boolean hasChildFocus;
	static Callback menuItemSelectedFunc = new Callback(ToolBar.class, "MenuItemSelectedProc", 2);
	String cssBackground, cssForeground = " ";

/**
 * 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#FLAT
 * @see SWT#WRAP
 * @see SWT#RIGHT
 * @see SWT#HORIZONTAL
 * @see SWT#SHADOW_OUT
 * @see SWT#VERTICAL
 * @see Widget#checkSubclass()
 * @see Widget#getStyle()
 */
public ToolBar (Composite parent, int style) {
	super (parent, checkStyle (style));
	/*
	* Ensure that either of HORIZONTAL or VERTICAL is set.
	* NOTE: HORIZONTAL and VERTICAL have the same values
	* as H_SCROLL and V_SCROLL so it is necessary to first
	* clear these bits to avoid scroll bars and then reset
	* the bits using the original style supplied by the
	* programmer.
	*/
	if ((style & SWT.VERTICAL) != 0) {
		this.style |= SWT.VERTICAL;
	} else {
		this.style |= SWT.HORIZONTAL;
	}
	int orientation = (style & SWT.VERTICAL) != 0 ? GTK.GTK_ORIENTATION_VERTICAL : GTK.GTK_ORIENTATION_HORIZONTAL;
	GTK.gtk_orientable_set_orientation(handle, orientation);
}

static int checkStyle (int style) {
	/*
	* Even though it is legal to create this widget
	* with scroll bars, they serve no useful purpose
	* because they do not automatically scroll the
	* widget's client area.  The fix is to clear
	* the SWT style.
	*/
	return style & ~(SWT.H_SCROLL | SWT.V_SCROLL);
}

@Override
protected void checkSubclass () {
	if (!isValidSubclass ()) error (SWT.ERROR_INVALID_SUBCLASS);
}

@Override
void createHandle (int index) {
	state |= HANDLE | THEME_BACKGROUND;
	fixedHandle = OS.g_object_new (display.gtk_fixed_get_type (), 0);
	if (fixedHandle == 0) error (SWT.ERROR_NO_HANDLES);
	gtk_widget_set_has_surface_or_window (fixedHandle, true);

	if (GTK.GTK4) {
		handle = GTK.gtk_box_new(GTK.GTK_ORIENTATION_HORIZONTAL, 0);
		GTK.gtk_widget_add_css_class(handle, Converter.javaStringToCString("toolbar"));
	} else {
		handle = GTK.gtk_toolbar_new ();
	}

	if (handle == 0) error (SWT.ERROR_NO_HANDLES);

	if (GTK.GTK4) {
		OS.swt_fixed_add(fixedHandle, handle);
	} else {
		GTK.gtk_container_add (fixedHandle, handle);
	}

	/*
	* Bug in GTK.  GTK will segment fault if gtk_widget_reparent() is called
	* on a tool bar or on a widget hierarchy containing a tool bar when the icon
	* size is not GTK_ICON_SIZE_LARGE_TOOLBAR.  The fix is to set the icon
	* size to GTK_ICON_SIZE_LARGE_TOOLBAR.
	*
	* Note that the segmentation fault does not happen on GTK 3, but the
	* tool bar preferred size is too big with GTK_ICON_SIZE_LARGE_TOOLBAR
	* when the tool bar item has no image or text.
	*/
	if (!GTK.GTK4) GTK.gtk_toolbar_set_icon_size (handle, GTK.GTK_ICON_SIZE_SMALL_TOOLBAR);

	// In GTK 3 font description is inherited from parent widget which is not how SWT has always worked,
	// reset to default font to get the usual behavior
	setFontDescription(defaultFont().handle);
}

@Override
int applyThemeBackground () {
	return -1; /* No Change */
}

@Override
Point computeSizeInPixels (int wHint, int hHint, boolean changed) {
	checkWidget ();
	if (wHint != SWT.DEFAULT && wHint < 0) wHint = 0;
	if (hHint != SWT.DEFAULT && hHint < 0) hHint = 0;

	Point size = null;

	if (GTK.GTK4) {
		size = computeNativeSize (handle, wHint, hHint, changed);
	} else {
		/*
		 * Feature in GTK. Size of toolbar is calculated incorrectly
		 * and appears as just the overflow arrow, if the arrow is enabled
		 * to display. The fix is to disable it before the computation of
		 * size and enable it if WRAP style is set.
		 */
		GTK.gtk_toolbar_set_show_arrow (handle, false);
		size = computeNativeSize (handle, wHint, hHint, changed);
		if ((style & SWT.WRAP) != 0) GTK.gtk_toolbar_set_show_arrow (handle, true);
	}

	return size;
}

@Override
Widget computeTabGroup () {
	ToolItem [] items = _getItems ();
	if (tabItemList == null) {
		int i = 0;
		while (i < items.length && items [i].control == null) i++;
		if (i == items.length) return super.computeTabGroup ();
	}
	int index = indexOf(currentFocusItem);
	if (index == -1) index = items.length - 1;
	while (index >= 0) {
		ToolItem item = items [index];
		if (item.isTabGroup ()) return item;
		index--;
	}
	return super.computeTabGroup ();
}

@Override
Widget [] computeTabList () {
	ToolItem [] items = _getItems ();
	if (tabItemList == null) {
		int i = 0;
		while (i < items.length && items [i].control == null) i++;
		if (i == items.length) return super.computeTabList ();
	}
	Widget result [] = {};
	if (!isTabGroup () || !isEnabled () || !isVisible ()) return result;
	ToolItem [] list = tabList != null ? _getTabItemList () : items;
	for (int i=0; i<list.length; i++) {
		ToolItem child = list [i];
		Widget  [] childList = child.computeTabList ();
		if (childList.length != 0) {
			Widget [] newResult = new Widget [result.length + childList.length];
			System.arraycopy (result, 0, newResult, 0, result.length);
			System.arraycopy (childList, 0, newResult, result.length, childList.length);
			result = newResult;
		}
	}
	if (result.length == 0) result = new Widget [] {this};
	return result;
}

@Override
long eventHandle () {
	return fixedHandle;
}

@Override
long enterExitHandle() {
	return handle;
}

@Override
void fixChildren (Shell newShell, Shell oldShell, Decorations newDecorations, Decorations oldDecorations, Menu [] menus) {
	super.fixChildren (newShell, oldShell, newDecorations, oldDecorations, menus);
	ToolItem [] items = getItems ();
	if (toolTipText == null) {
		for (int i = 0; i < items.length; i++) {
			ToolItem item = items [i];
			if (item.toolTipText != null) {
				item.setToolTipText(oldShell, null);
				item.setToolTipText(newShell, item.toolTipText);
			}
		}
	}
}

@Override
boolean forceFocus (long focusHandle) {
	int dir = GTK.GTK_DIR_TAB_FORWARD;
	if ((style & SWT.MIRRORED) != 0) dir = GTK.GTK_DIR_TAB_BACKWARD;
	long childHandle = handle;
	if (currentFocusItem != null)  childHandle = currentFocusItem.handle;
	/*
	 * Feature in GTK. GtkToolBar takes care of navigating through
	 * items by Up/Down arrow keys.
	 */
	if (GTK.gtk_widget_child_focus (childHandle, dir)) return true;
	return super.forceFocus (focusHandle);
}

/**
 * Returns the item at the given, zero-relative index in the
 * receiver. Throws an exception if the index is out of range.
 *
 * @param index the index of the item to return
 * @return the item at the given index
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the list minus 1 (inclusive)</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 ToolItem getItem (int index) {
	checkWidget();
	if (!(0 <= index && index < getItemCount())) error (SWT.ERROR_INVALID_RANGE);
	return getItems()[index];
}

/**
 * Returns the item at the given point in the receiver
 * or null if no such item exists. The point is in the
 * coordinate system of the receiver.
 *
 * @param point the point used to locate the item
 * @return the item at the given point
 *
 * @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 ToolItem getItem (Point point) {
	checkWidget();
	return getItemInPixels(DPIUtil.autoScaleUp(point));
}


ToolItem getItemInPixels (Point point) {
	if (point == null) error (SWT.ERROR_NULL_ARGUMENT);
	ToolItem[] items = getItems();
	for (int i=0; i<items.length; i++) {
		if (items[i].getBoundsInPixels().contains(point)) return items[i];
	}
	return null;
}

/**
 * Returns the number of items contained in the receiver.
 *
 * @return the number of items
 *
 * @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 getItemCount () {
	checkWidget();

	int itemCount = 0;
	if (GTK.GTK4) {
		for (long child = GTK.gtk_widget_get_first_child(handle); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
			itemCount++;
		}
	} else {
		long list = GTK.gtk_container_get_children (handle);
		if (list == 0) return 0;
		itemCount = OS.g_list_length (list);
		OS.g_list_free (list);
	}

	return itemCount;
}

/**
 * Returns an array of <code>ToolItem</code>s which are the items
 * in the receiver.
 * <p>
 * Note: This is not the actual structure used by the receiver
 * to maintain its list of items, so modifying the array will
 * not affect the receiver.
 * </p>
 *
 * @return the items in 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 ToolItem [] getItems () {
	checkWidget();
	return _getItems ();
}

ToolItem[] _getItems () {
	if (GTK.GTK4) {
		ArrayList<ToolItem> childrenList = new ArrayList<>();
		for (long child = GTK.gtk_widget_get_first_child(handle); child != 0; child = GTK.gtk_widget_get_next_sibling(child)) {
			Widget childWidget = display.getWidget(child);
			if (childWidget != null) {
				childrenList.add((ToolItem)childWidget);
			}
		}

		return childrenList.toArray(new ToolItem[childrenList.size()]);
	} else {
		long list = GTK.gtk_container_get_children (handle);
		if (list == 0) return new ToolItem [0];
		int count = OS.g_list_length (list);
		ToolItem [] items = new ToolItem [count];
		long originalList = list;
		int index = 0;
		for (int i=0; i<count; i++) {
			long data = OS.g_list_data (list);
			Widget widget = display.getWidget (data);
			if (widget != null) items [index++] = (ToolItem) widget;
			list = OS.g_list_next (list);
		}
		OS.g_list_free (originalList);
		if (index != items.length) {
			ToolItem [] newItems = new ToolItem [index];
			System.arraycopy (items, 0, newItems, 0, index);
			items = newItems;
		}
		return items;
	}
}

/**
 * Returns the number of rows in the receiver. When
 * the receiver has the <code>WRAP</code> style, the
 * number of rows can be greater than one.  Otherwise,
 * the number of rows is always one.
 *
 * @return the number of items
 *
 * @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 getRowCount () {
	checkWidget();
	/* On GTK, toolbars cannot wrap */
	return 1;
}

ToolItem [] _getTabItemList () {
	if (tabItemList == null) return tabItemList;
	int count = 0;
	for (int i=0; i<tabItemList.length; i++) {
		if (!tabItemList [i].isDisposed ()) count++;
	}
	if (count == tabItemList.length) return tabItemList;
	ToolItem [] newList = new ToolItem [count];
	int index = 0;
	for (int i=0; i<tabItemList.length; i++) {
		if (!tabItemList [i].isDisposed ()) {
			newList [index++] = tabItemList [i];
		}
	}
	tabItemList = newList;
	return tabItemList;
}

@Override
long gtk_key_press_event (long widget, long eventPtr) {
	if (!hasFocus ()) return 0;
	long result = super.gtk_key_press_event (widget, eventPtr);
	return result;
}

@Override
long gtk_focus (long widget, long directionType) {
	return 0;
}

@Override
boolean hasFocus () {
	if (hasChildFocus) return true;
	return super.hasFocus();
}

/**
 * Searches the receiver's list starting at the first item
 * (index 0) until an item is found that is equal to the
 * argument, and returns the index of that item. If no item
 * is found, returns -1.
 *
 * @param item the search item
 * @return the index of the item
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the tool item is null</li>
 *    <li>ERROR_INVALID_ARGUMENT - if the tool item 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 int indexOf (ToolItem item) {
	checkWidget();
	if (item == null) error (SWT.ERROR_NULL_ARGUMENT);
	ToolItem [] items = getItems ();
	for (int i=0; i<items.length; i++) {
		if (item == items[i]) return i;
	}
	return -1;
}

static long MenuItemSelectedProc (long widget, long /*int*/	user_data) {
	Display display = Display.getCurrent ();
	ToolItem item = (ToolItem) display.getWidget (user_data);
	if (item != null) {
		return item.getParent ().menuItemSelected (widget, item);
	}
	return 0;
}

long menuItemSelected (long widget, ToolItem item) {
	Event event = new Event ();
	switch (item.style) {
		case SWT.DROP_DOWN :
			/*
			 * Feature in GTK. The DROP_DOWN item does not
			 * contain arrow button in the overflow menu. So, it
			 * is impossible to select the menu of that item.
			 * The fix is to consider the item selection
			 * as Arrow click, in order to popup the drop-down.
			 */
			event.detail = SWT.ARROW;
			GtkAllocation allocation = new GtkAllocation ();
			GTK.gtk_widget_get_allocation (widget, allocation);
			event.x = DPIUtil.autoScaleDown(allocation.x);
			if ((style & SWT.MIRRORED) != 0) event.x = DPIUtil.autoScaleDown (getClientWidth () - allocation.width) - event.x;
			event.y = DPIUtil.autoScaleDown(allocation.y + allocation.height);
			break;
		case SWT.RADIO :
			if ((style & SWT.NO_RADIO_GROUP) == 0)	item.selectRadio ();
			break;
		case SWT.CHECK :
			boolean currentSelection = item.getSelection();
			item.setSelection (!currentSelection);
	}
	item.sendSelectionEvent  (SWT.Selection, event, false);
	return 0;
}

@Override
boolean mnemonicHit (char key) {
	ToolItem [] items = getItems ();
	for (int i=0; i<items.length; i++) {
		long labelHandle = items [i].labelHandle;
		if (labelHandle != 0 && mnemonicHit (labelHandle, key)) return true;
	}
	return false;
}

@Override
boolean mnemonicMatch (char key) {
	ToolItem [] items = getItems ();
	for (int i=0; i<items.length; i++) {
		long labelHandle = items [i].labelHandle;
		if (labelHandle != 0 && mnemonicMatch (labelHandle, key)) return true;
	}
	return false;
}

void relayout () {
	ToolItem [] items = getItems ();
	boolean hasText = false, hasImage = false;
	for (int i=0; i<items.length; i++) {
		ToolItem item = items [i];
		if (item != null) {
			item.resizeControl ();
			hasText |= item.text != null && item.text.length() > 0;
			hasImage |= item.image != null;
		}
	}

	if (GTK.GTK4) {
		/* TODO: GTK4 no more GtkToolbar, we have to use a generic GtkBox
		 * therefore we will need to implement these style ourselves. */
	} else {
		int type = GTK.GTK_TOOLBAR_ICONS;
		if (hasText && hasImage) {
			if ((style & SWT.RIGHT) != 0) {
				type = GTK.GTK_TOOLBAR_BOTH_HORIZ;
			} else {
				type = GTK.GTK_TOOLBAR_BOTH;
			}
		} else if (hasText) {
			type = GTK.GTK_TOOLBAR_TEXT;
		} else if (hasImage) {
			type = GTK.GTK_TOOLBAR_ICONS;
		}
		GTK.gtk_toolbar_set_style (handle, type);
	}
}

@Override
void releaseChildren (boolean destroy) {
	ToolItem [] items = getItems ();
	for (int i=0; i<items.length; i++) {
		ToolItem item = items [i];
		if (item != null && !item.isDisposed ()) {
			item.release (false);
		}
	}
	super.releaseChildren (destroy);
}

@Override
void releaseWidget () {
	super.releaseWidget ();
	if (imageList != null) imageList.dispose ();
	imageList = null;
}

@Override
void removeControl (Control control) {
	super.removeControl (control);
	ToolItem [] items = getItems ();
	for (int i=0; i<items.length; i++) {
		ToolItem item = items [i];
		if (item.control == control) item.setControl (null);
	}
}

@Override
void reskinChildren (int flags) {
	ToolItem[] items = _getItems();
	if (items != null) {
		for (int i=0; i<items.length; i++) {
			ToolItem item = items [i];
			if (item != null) item.reskin (flags);
		}
	}
	super.reskinChildren (flags);
}

@Override
int setBounds (int x, int y, int width, int height, boolean move, boolean resize) {
	if (!GTK.GTK4) GTK.gtk_toolbar_set_show_arrow (handle, false);
	int result = super.setBounds (x, y, width, height, move, resize);
	if ((result & RESIZED) != 0) relayout ();
	if ((style & SWT.WRAP) != 0) {
		if (GTK.GTK4) {
			/* TODO: GTK4 will require us to implement our own
			 * overflow menu. May require the use of the "toolbar" style class
			 * applied to the widget.  */
		} else {
			GTK.gtk_toolbar_set_show_arrow (handle, true);
		}
	}

	return result;
}

@Override
void setBackgroundGdkRGBA (long context, long handle, GdkRGBA rgba) {
	// Form background string
	String css = "toolbar {background-color: " + display.gtk_rgba_to_css_string(rgba) + "}";

	// Cache background color
	this.cssBackground = css;

	// Apply background color and any foreground color
	String finalCss = display.gtk_css_create_css_color_string (this.cssBackground, this.cssForeground, SWT.BACKGROUND);
	gtk_css_provider_load_from_css(context, finalCss);
}

@Override
void setParentBackground () {
	setBackgroundGdkRGBA (handle, display.getSystemColor(SWT.COLOR_TRANSPARENT).handle);
	super.setParentBackground();
}

@Override
void setForegroundGdkRGBA (long handle, GdkRGBA rgba) {
	GdkRGBA toSet = new GdkRGBA();
	if (rgba != null) {
		toSet = rgba;
	} else {
		toSet = display.COLOR_WIDGET_FOREGROUND_RGBA;
	}
	long context = GTK.gtk_widget_get_style_context (handle);
	// Form foreground string
	String color = display.gtk_rgba_to_css_string(toSet);
	String name = display.gtk_widget_class_get_css_name(handle);
	GdkRGBA selectedForeground = display.COLOR_LIST_SELECTION_TEXT_RGBA;
	String css = "* {color: " + color + ";}\n"
			+ name + " selection {color: " + display.gtk_rgba_to_css_string(selectedForeground) + ";}";

	// Cache foreground color
	this.cssForeground = css;

	// Apply foreground color and any cached background color
	String finalCss = display.gtk_css_create_css_color_string (this.cssBackground, this.cssForeground, SWT.FOREGROUND);
	gtk_css_provider_load_from_css(context, finalCss);
}

@Override
void setFontDescription (long font) {
	super.setFontDescription (font);
	ToolItem [] items = getItems ();
	for (int i = 0; i < items.length; i++) {
		items[i].setFontDescription (font);
	}
	relayout ();
}

void restoreBackground () {
	/*
	 * We need to restore the cached background color in order to prevent
	 * setting the foreground color from overriding the background color
	 * (or replacing it with black).
	 */
	long context = GTK.gtk_widget_get_style_context(handle);
	String finalCss = display.gtk_css_create_css_color_string (this.cssBackground, this.cssForeground, SWT.BACKGROUND);
	gtk_css_provider_load_from_css (context, finalCss);
}

@Override
void setForegroundGdkRGBA (GdkRGBA rgba) {
	super.setForegroundGdkRGBA (rgba);
	ToolItem [] items = getItems ();
	for (int i = 0; i < items.length; i++) {
		items[i].setForegroundRGBA (rgba);
	}
}

@Override
void setOrientation (boolean create) {
	super.setOrientation (create);
	ToolItem [] items = _getItems ();
	for (int i = 0; i < items.length; i++) {
		items[i].setOrientation (create);
	}
}

/*public*/ void setTabItemList (ToolItem [] tabList) {
	checkWidget ();
	if (tabList != null) {
		for (int i=0; i<tabList.length; i++) {
			ToolItem item = tabList [i];
			if (item == null) error (SWT.ERROR_INVALID_ARGUMENT);
			if (item.isDisposed ()) error (SWT.ERROR_INVALID_ARGUMENT);
			if (item.parent != this) error (SWT.ERROR_INVALID_PARENT);
		}
		ToolItem [] newList = new ToolItem [tabList.length];
		System.arraycopy (tabList, 0, newList, 0, tabList.length);
		tabList = newList;
	}
	this.tabItemList = tabList;
}

@Override
public void setToolTipText (String string) {
	checkWidget();
	super.setToolTipText (string);
	Shell shell = _getShell ();
	ToolItem [] items = getItems ();
	for (int i = 0; i < items.length; i++) {
		String newString = string != null ? null : items [i].toolTipText;
		shell.setToolTipText (items [i].handle, newString);
	}
}

}