/*******************************************************************************
 * Copyright (c) 2000, 2016 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 org.eclipse.swt.*;
import org.eclipse.swt.events.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.internal.*;
import org.eclipse.swt.internal.win32.*;

/**
 * Instances of this class represent a selectable user interface
 * object that displays a list of strings and issues notification
 * when a string is selected.  A list may be single or multi select.
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>SINGLE, MULTI, NO_SEARCH</dd>
 * <dt><b>Events:</b></dt>
 * <dd>Selection, DefaultSelection</dd>
 * </dl>
 * <p>
 * Note: Only one of SINGLE and MULTI may be specified.
 * </p><p>
 * IMPORTANT: This class is <em>not</em> intended to be subclassed.
 * </p>
 *
 * @see <a href="https://eclipse.dev/eclipse/swt/snippets/#list">List snippets</a>
 * @see <a href="https://eclipse.dev/eclipse/swt/examples.html">SWT Example: ControlExample</a>
 * @see <a href="https://eclipse.dev/eclipse/swt/">Sample code and further information</a>
 * @noextend This class is not intended to be subclassed by clients.
 */
public class List extends Scrollable {
	static final int INSET = 3;
	static final long ListProc;
	static final TCHAR ListClass = new TCHAR (0, "LISTBOX", true);
	boolean addedUCC = false; // indicates whether Bidi UCC were added; 'state & HAS_AUTO_DIRECTION' isn't a sufficient indicator
	static {
		WNDCLASS lpWndClass = new WNDCLASS ();
		OS.GetClassInfo (0, ListClass, lpWndClass);
		ListProc = lpWndClass.lpfnWndProc;
	}

/**
 * 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#SINGLE
 * @see SWT#MULTI
 * @see Widget#checkSubclass
 * @see Widget#getStyle
 */
public List (Composite parent, int style) {
	super (parent, checkStyle (style));
}
/**
 * Adds the argument to the end of the receiver's list.
 * <p>
 * Note: If control characters like '\n', '\t' etc. are used
 * in the string, then the behavior is platform dependent.
 * </p>
 * @param string the new item
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the string 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 #add(String,int)
 */
public void add (String string) {
	checkWidget ();
	if (string == null) error (SWT.ERROR_NULL_ARGUMENT);
	TCHAR buffer = new TCHAR (getCodePage (), string, true);
	int result = (int)OS.SendMessage (handle, OS.LB_ADDSTRING, 0, buffer);
	if (result == OS.LB_ERR) error (SWT.ERROR_ITEM_NOT_ADDED);
	if (result == OS.LB_ERRSPACE) error (SWT.ERROR_ITEM_NOT_ADDED);
	if ((style & SWT.H_SCROLL) != 0) setScrollWidth (buffer.chars, true);
}
/**
 * Adds the argument to the receiver's list at the given
 * zero-relative index.
 * <p>
 * Note: To add an item at the end of the list, use the
 * result of calling <code>getItemCount()</code> as the
 * index or use <code>add(String)</code>.
 * </p><p>
 * Also note, if control characters like '\n', '\t' etc. are used
 * in the string, then the behavior is platform dependent.
 * </p>
 *
 * @param string the new item
 * @param index the index for the item
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the string is null</li>
 *    <li>ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the list (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>
 *
 * @see #add(String)
 */
public void add (String string, int index) {
	checkWidget ();
	if (string == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (index == -1) error (SWT.ERROR_INVALID_RANGE);
	TCHAR buffer = new TCHAR (getCodePage (), string, true);
	int result = (int)OS.SendMessage (handle, OS.LB_INSERTSTRING, index, buffer);
	if (result == OS.LB_ERRSPACE) error (SWT.ERROR_ITEM_NOT_ADDED);
	if (result == OS.LB_ERR) {
		int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
		if (0 <= index && index <= count) {
			error (SWT.ERROR_ITEM_NOT_ADDED);
		} else {
			error (SWT.ERROR_INVALID_RANGE);
		}
	}
	if ((style & SWT.H_SCROLL) != 0) setScrollWidth (buffer.chars, true);
}

/**
 * Adds the listener to the collection of listeners who will
 * be notified when the user changes the receiver's selection, by sending
 * it one of the messages defined in the <code>SelectionListener</code>
 * interface.
 * <p>
 * <code>widgetSelected</code> is called when the selection changes.
 * <code>widgetDefaultSelected</code> is typically called when an item is double-clicked.
 * </p>
 *
 * @param listener the listener which should be notified when the user changes the receiver's selection
 *
 * @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) {
	addTypedListener(listener, SWT.Selection, SWT.DefaultSelection);
}

@Override
long callWindowProc (long hwnd, int msg, long wParam, long lParam) {
	if (handle == 0) return 0;
	boolean redraw = false;
	switch (msg) {
		case OS.WM_HSCROLL:
		case OS.WM_VSCROLL: {
			redraw = findImageControl () != null && getDrawing() && OS.IsWindowVisible (handle);
			if (redraw) OS.DefWindowProc (handle, OS.WM_SETREDRAW, 0, 0);
			break;
		}
	}
	long code = OS.CallWindowProc (ListProc, hwnd, msg, wParam, lParam);
	switch (msg) {
		case OS.WM_HSCROLL:
		case OS.WM_VSCROLL: {
			if (redraw) {
				OS.DefWindowProc (handle, OS.WM_SETREDRAW, 1, 0);
				OS.InvalidateRect (handle, null, true);
			}
			break;
		}
	}
	return code;
}

static int checkStyle (int style) {
	return checkBits (style, SWT.SINGLE, SWT.MULTI, 0, 0, 0, 0);
}

@Override
Point computeSizeInPixels (Point hintInPoints, int zoom, boolean changed) {
	checkWidget ();
	Point hintInPixels = Win32DPIUtils.pointToPixelAsSufficientlyLargeSize(hintInPoints, zoom);
	int width = 0, height = 0;
	if (hintInPoints.x == SWT.DEFAULT) {
		if ((style & SWT.H_SCROLL) != 0) {
			width = (int)OS.SendMessage (handle, OS.LB_GETHORIZONTALEXTENT, 0, 0);
			width -= INSET;
		} else {
			int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
			long newFont, oldFont = 0;
			long hDC = OS.GetDC (handle);
			newFont = OS.SendMessage (handle, OS.WM_GETFONT, 0, 0);
			if (newFont != 0) oldFont = OS.SelectObject (hDC, newFont);
			RECT rect = new RECT ();
			int flags = OS.DT_CALCRECT | OS.DT_SINGLELINE | OS.DT_NOPREFIX;
			char [] buffer = new char [64 + 1];
			for (int i=0; i<count; i++) {
				int length = (int)OS.SendMessage (handle, OS.LB_GETTEXTLEN, i, 0);
				if (length != OS.LB_ERR) {
					if (length + 1 > buffer.length) {
						buffer = new char [length + 1];
					}
					int result = (int)OS.SendMessage (handle, OS.LB_GETTEXT, i, buffer);
					if (result != OS.LB_ERR) {
						OS.DrawText (hDC, buffer, length, rect, flags);
						width = Math.max (width, rect.right - rect.left);
					}
				}
			}
			if (newFont != 0) OS.SelectObject (hDC, oldFont);
			OS.ReleaseDC (handle, hDC);
		}
	}
	if (hintInPoints.y == SWT.DEFAULT) {
		int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
		int itemHeight = (int)OS.SendMessage (handle, OS.LB_GETITEMHEIGHT, 0, 0);
		height = count * itemHeight;
	}
	if (width == 0) width = DEFAULT_WIDTH;
	if (height == 0) height = DEFAULT_HEIGHT;
	if (hintInPoints.x != SWT.DEFAULT) width = hintInPixels.x;
	if (hintInPoints.y != SWT.DEFAULT) height = hintInPixels.y;
	int border = getBorderWidthInPixels ();
	width += border * 2 + INSET;
	height += border * 2;
	if ((style & SWT.V_SCROLL) != 0) {
		width += getSystemMetrics (OS.SM_CXVSCROLL);
	}
	if ((style & SWT.H_SCROLL) != 0) {
		height += getSystemMetrics (OS.SM_CYHSCROLL);
	}
	return new Point (width, height);
}

@Override
int defaultBackground () {
	return OS.GetSysColor (OS.COLOR_WINDOW);
}

/**
 * Deselects the items at the given zero-relative indices in the receiver.
 * If the item at the given zero-relative index in the receiver
 * is selected, it is deselected.  If the item at the index
 * was not selected, it remains deselected. Indices that are out
 * of range and duplicate indices are ignored.
 *
 * @param indices the array of indices for the items to deselect
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the set of indices 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 deselect (int [] indices) {
	checkWidget ();
	if (indices == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (indices.length == 0) return;
	if ((style & SWT.SINGLE) != 0) {
		int oldIndex = (int)OS.SendMessage (handle, OS.LB_GETCURSEL, 0, 0);
		if (oldIndex == OS.LB_ERR) return;
		for (int index : indices) {
			if (oldIndex == index) {
				OS.SendMessage (handle, OS.LB_SETCURSEL, -1, 0);
				return;
			}
		}
		return;
	}
	for (int index : indices) {
		if (index != -1) {
			OS.SendMessage (handle, OS.LB_SETSEL, 0, index);
		}
	}
}

/**
 * Deselects the item at the given zero-relative index in the receiver.
 * If the item at the index was already deselected, it remains
 * deselected. Indices that are out of range are ignored.
 *
 * @param index the index of the item to deselect
 *
 * @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 deselect (int index) {
	checkWidget ();
	if (index == -1) return;
	if ((style & SWT.SINGLE) != 0) {
		int oldIndex = (int)OS.SendMessage (handle, OS.LB_GETCURSEL, 0, 0);
		if (oldIndex == OS.LB_ERR) return;
		if (oldIndex == index) OS.SendMessage (handle, OS.LB_SETCURSEL, -1, 0);
		return;
	}
	OS.SendMessage (handle, OS.LB_SETSEL, 0, index);
}

/**
 * Deselects the items at the given zero-relative indices in the receiver.
 * If the item at the given zero-relative index in the receiver
 * is selected, it is deselected.  If the item at the index
 * was not selected, it remains deselected.  The range of the
 * indices is inclusive. Indices that are out of range are ignored.
 *
 * @param start the start index of the items to deselect
 * @param end the end index of the items to deselect
 *
 * @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 deselect (int start, int end) {
	checkWidget ();
	if (start > end) return;
	if ((style & SWT.SINGLE) != 0) {
		int oldIndex = (int)OS.SendMessage (handle, OS.LB_GETCURSEL, 0, 0);
		if (oldIndex == OS.LB_ERR) return;
		if (start <= oldIndex && oldIndex <= end) {
			OS.SendMessage (handle, OS.LB_SETCURSEL, -1, 0);
		}
		return;
	}
	/*
	* Ensure that at least one item is contained in
	* the range from start to end.  Note that when
	* start = end, LB_SELITEMRANGEEX deselects the
	* item.
	*/
	int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	if (start < 0 && end < 0) return;
	if (start >= count && end >= count) return;
	start = Math.min (count - 1, Math.max (0, start));
	end = Math.min (count - 1, Math.max (0, end));
	OS.SendMessage (handle, OS.LB_SELITEMRANGEEX, end, start);
}

/**
 * Deselects all selected 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 void deselectAll () {
	checkWidget ();
	if ((style & SWT.SINGLE) != 0) {
		OS.SendMessage (handle, OS.LB_SETCURSEL, -1, 0);
	} else {
		OS.SendMessage (handle, OS.LB_SETSEL, 0, -1);
	}
}

/**
 * Returns the zero-relative index of the item which currently
 * has the focus in the receiver, or -1 if no item has focus.
 *
 * @return the index of the selected item
 *
 * @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 getFocusIndex () {
	checkWidget ();
	int result = (int)OS.SendMessage (handle, OS.LB_GETCARETINDEX, 0, 0);
	if (result == 0) {
		int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
		if (count == 0) return -1;
	}
	return result;
}

/**
 * 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 String getItem (int index) {
	checkWidget ();
	int length = (int)OS.SendMessage (handle, OS.LB_GETTEXTLEN, index, 0);
	if (length != OS.LB_ERR) {
		char [] buffer = new char [length + 1];
		int result = (int)OS.SendMessage (handle, OS.LB_GETTEXT, index, buffer);
		if (result != OS.LB_ERR) return ((state & HAS_AUTO_DIRECTION) != 0) ? new String (buffer, 1, length - 1) : new String (buffer, 0, length);
	}
	int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	if (0 <= index && index < count) error (SWT.ERROR_CANNOT_GET_ITEM);
	error (SWT.ERROR_INVALID_RANGE);
	return "";
}

/**
 * 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 result = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	if (result == OS.LB_ERR) error (SWT.ERROR_CANNOT_GET_COUNT);
	return result;
}

/**
 * Returns the height of the area which would be used to
 * display <em>one</em> of the items in the list.
 *
 * @return the height of one item
 *
 * @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 getItemHeight () {
	checkWidget ();
	return DPIUtil.pixelToPoint(getItemHeightInPixels(), getAutoscalingZoom());
}

int getItemHeightInPixels () {
	int result = (int)OS.SendMessage (handle, OS.LB_GETITEMHEIGHT, 0, 0);
	if (result == OS.LB_ERR) error (SWT.ERROR_CANNOT_GET_ITEM_HEIGHT);
	return result;
}

/**
 * Returns a (possibly empty) array of <code>String</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's list
 *
 * @exception SWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 */
public String [] getItems () {
	checkWidget ();
	int count = getItemCount ();
	String [] result = new String [count];
	for (int i=0; i<count; i++) result [i] = getItem (i);
	return result;
}

/**
 * Returns an array of <code>String</code>s that are currently
 * selected in the receiver.  The order of the items is unspecified.
 * An empty array indicates that no items are selected.
 * <p>
 * Note: This is not the actual structure used by the receiver
 * to maintain its selection, so modifying the array will
 * not affect the receiver.
 * </p>
 * @return an array representing the selection
 *
 * @exception SWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 */
public String [] getSelection () {
	checkWidget ();
	int [] indices = getSelectionIndices ();
	String [] result = new String [indices.length];
	for (int i=0; i<indices.length; i++) {
		result [i] = getItem (indices [i]);
	}
	return result;
}

/**
 * Returns the number of selected items contained in the receiver.
 *
 * @return the number of selected 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 getSelectionCount () {
	checkWidget ();
	if ((style & SWT.SINGLE) != 0) {
		int result = (int)OS.SendMessage (handle, OS.LB_GETCURSEL, 0, 0);
		if (result == OS.LB_ERR) return 0;
		return 1;
	}
	int result = (int)OS.SendMessage (handle, OS.LB_GETSELCOUNT, 0, 0);
	if (result == OS.LB_ERR) error (SWT.ERROR_CANNOT_GET_COUNT);
	return result;
}

/**
 * Returns the zero-relative index of the item which is currently
 * selected in the receiver, or -1 if no item is selected.
 *
 * @return the index of the selected item or -1
 *
 * @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 getSelectionIndex () {
	checkWidget ();
	if ((style & SWT.SINGLE) != 0) {
		return (int)OS.SendMessage (handle, OS.LB_GETCURSEL, 0, 0);
	}
	int count = (int)OS.SendMessage (handle, OS.LB_GETSELCOUNT, 0, 0);
	if (count == OS.LB_ERR) error (SWT.ERROR_CANNOT_GET_SELECTION);
	if (count == 0) return -1;
	int index = (int)OS.SendMessage (handle, OS.LB_GETCARETINDEX, 0, 0);
	int result = (int)OS.SendMessage (handle, OS.LB_GETSEL, index, 0);
	if (result == OS.LB_ERR) error (SWT.ERROR_CANNOT_GET_SELECTION);
	if (result != 0) return index;
	int [] buffer = new int[1];
	result = (int)OS.SendMessage (handle, OS.LB_GETSELITEMS, 1, buffer);
	if (result != 1) error (SWT.ERROR_CANNOT_GET_SELECTION);
	return buffer [0];
}

/**
 * Returns the zero-relative indices of the items which are currently
 * selected in the receiver.  The order of the indices is unspecified.
 * The array is empty if no items are selected.
 * <p>
 * Note: This is not the actual structure used by the receiver
 * to maintain its selection, so modifying the array will
 * not affect the receiver.
 * </p>
 * @return the array of indices of the selected 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 [] getSelectionIndices () {
	checkWidget ();
	if ((style & SWT.SINGLE) != 0) {
		int result = (int)OS.SendMessage (handle, OS.LB_GETCURSEL, 0, 0);
		if (result == OS.LB_ERR) return new int [0];
		return new int [] {result};
	}
	int length = (int)OS.SendMessage (handle, OS.LB_GETSELCOUNT, 0, 0);
	if (length == OS.LB_ERR) error (SWT.ERROR_CANNOT_GET_SELECTION);
	int [] indices = new int [length];
	int result = (int)OS.SendMessage (handle, OS.LB_GETSELITEMS, length, indices);
	if (result != length) error (SWT.ERROR_CANNOT_GET_SELECTION);
	return indices;
}

/**
 * Returns the zero-relative index of the item which is currently
 * at the top of the receiver. This index can change when items are
 * scrolled or new items are added or removed.
 *
 * @return the index of the top item
 *
 * @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 getTopIndex () {
	checkWidget ();
	return (int)OS.SendMessage (handle, OS.LB_GETTOPINDEX, 0, 0);
}

/**
 * Gets the index of an item.
 * <p>
 * The list is searched starting at 0 until an
 * item is found that is equal to the search item.
 * If no item is found, -1 is returned.  Indexing
 * is zero based.
 *
 * @param string the search item
 * @return the index of the item
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the string 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 int indexOf (String string) {
	return indexOf (string, 0);
}

/**
 * Searches the receiver's list starting at the given,
 * zero-relative index until an item is found that is equal
 * to the argument, and returns the index of that item. If
 * no item is found or the starting index is out of range,
 * returns -1.
 *
 * @param string the search item
 * @param start the zero-relative index at which to start the search
 * @return the index of the item
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the string 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 int indexOf (String string, int start) {
	checkWidget ();
	if (string == null) error (SWT.ERROR_NULL_ARGUMENT);

	/*
	* Bug in Windows.  For some reason, LB_FINDSTRINGEXACT
	* will not find empty strings even though it is legal
	* to insert an empty string into a list.  The fix is
	* to search the list, an item at a time.
	*/
	if (string.length () == 0) {
		int count = getItemCount ();
		for (int i=start; i<count; i++) {
			if (string.equals (getItem (i))) return i;
		}
		return -1;
	}

	/* Use LB_FINDSTRINGEXACT to search for the item */
	int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	if (!(0 <= start && start < count)) return -1;
	int index = start - 1, last;
	TCHAR buffer = new TCHAR (getCodePage (), string, true);
	do {
		index = (int)OS.SendMessage (handle, OS.LB_FINDSTRINGEXACT, last = index, buffer);
		if (index == OS.LB_ERR || index <= last) return -1;
	} while (!string.equals (getItem (index)));
	return index;
}

/**
 * Returns <code>true</code> if the item is selected,
 * and <code>false</code> otherwise.  Indices out of
 * range are ignored.
 *
 * @param index the index of the item
 * @return the selection state of the item at the index
 *
 * @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 isSelected (int index) {
	checkWidget ();
	int result = (int)OS.SendMessage (handle, OS.LB_GETSEL, index, 0);
	return (result != 0) && (result != OS.LB_ERR);
}

@Override
boolean isUseWsBorder () {
	return super.isUseWsBorder () || ((display != null) && display.useWsBorderList);
}

/**
 * Removes the items from the receiver at the given
 * zero-relative indices.
 *
 * @param indices the array of indices of the items
 *
 * @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>
 *    <li>ERROR_NULL_ARGUMENT - if the indices array 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 remove (int [] indices) {
	checkWidget ();
	if (indices == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (indices.length == 0) return;
	int [] newIndices = new int [indices.length];
	System.arraycopy (indices, 0, newIndices, 0, indices.length);
	sort (newIndices);
	int start = newIndices [newIndices.length - 1], end = newIndices [0];
	int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	if (!(0 <= start && start <= end && end < count)) {
		error (SWT.ERROR_INVALID_RANGE);
	}
	int topIndex = (int)OS.SendMessage (handle, OS.LB_GETTOPINDEX, 0, 0);
	RECT rect = null;
	long hDC = 0, oldFont = 0, newFont = 0;
	int newWidth = 0;
	if ((style & SWT.H_SCROLL) != 0) {
		rect = new RECT ();
		hDC = OS.GetDC (handle);
		newFont = OS.SendMessage (handle, OS.WM_GETFONT, 0, 0);
		if (newFont != 0) oldFont = OS.SelectObject (hDC, newFont);
	}
	int i = 0, topCount = 0, last = -1;
	while (i < newIndices.length) {
		int index = newIndices [i];
		if (index != last) {
			char [] buffer = null;
			int length = 0;
			if ((style & SWT.H_SCROLL) != 0) {
				length = (int)OS.SendMessage (handle, OS.LB_GETTEXTLEN, index, 0);
				if (length == OS.LB_ERR) break;
				buffer = new char [length + 1];
				int result = (int)OS.SendMessage (handle, OS.LB_GETTEXT, index, buffer);
				if (result == OS.LB_ERR) break;
			}
			int result = (int)OS.SendMessage (handle, OS.LB_DELETESTRING, index, 0);
			if (result == OS.LB_ERR) break;
			if ((style & SWT.H_SCROLL) != 0) {
				int flags = OS.DT_CALCRECT | OS.DT_SINGLELINE | OS.DT_NOPREFIX;
				OS.DrawText (hDC, buffer, length, rect, flags);
				newWidth = Math.max (newWidth, rect.right - rect.left);
			}
			if (index < topIndex) topCount++;
			last = index;
		}
		i++;
	}
	if ((style & SWT.H_SCROLL) != 0) {
		if (newFont != 0) OS.SelectObject (hDC, oldFont);
		OS.ReleaseDC (handle, hDC);
		setScrollWidth (newWidth, false);
	}
	if (topCount > 0) {
		topIndex -= topCount;
	}
	OS.SendMessage (handle, OS.LB_SETTOPINDEX, topIndex, 0);
	if (i < newIndices.length) error (SWT.ERROR_ITEM_NOT_REMOVED);
}

/**
 * Removes the item from the receiver at the given
 * zero-relative index.
 *
 * @param index the index for the item
 *
 * @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 void remove (int index) {
	checkWidget ();
	char [] buffer = null;
	if ((style & SWT.H_SCROLL) != 0) {
		int length = (int)OS.SendMessage (handle, OS.LB_GETTEXTLEN, index, 0);
		if (length == OS.LB_ERR) {
			int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
			if (0 <= index && index < count) error (SWT.ERROR_ITEM_NOT_REMOVED);
			error (SWT.ERROR_INVALID_RANGE);
		}
		buffer = new char [length + 1];
		int result = (int)OS.SendMessage (handle, OS.LB_GETTEXT, index, buffer);
		if (result == OS.LB_ERR) {
			int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
			if (0 <= index && index < count) error (SWT.ERROR_ITEM_NOT_REMOVED);
			error (SWT.ERROR_INVALID_RANGE);
		}
	}
	int topIndex = (int)OS.SendMessage (handle, OS.LB_GETTOPINDEX, 0, 0);
	int result = (int)OS.SendMessage (handle, OS.LB_DELETESTRING, index, 0);
	if (result == OS.LB_ERR) {
		int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
		if (0 <= index && index < count) error (SWT.ERROR_ITEM_NOT_REMOVED);
		error (SWT.ERROR_INVALID_RANGE);
	}
	if ((style & SWT.H_SCROLL) != 0) setScrollWidth (buffer, false);
	if (index < topIndex) {
		topIndex -= 1;
	}
	OS.SendMessage (handle, OS.LB_SETTOPINDEX, topIndex, 0);
}

/**
 * Removes the items from the receiver which are
 * between the given zero-relative start and end
 * indices (inclusive).
 *
 * @param start the start of the range
 * @param end the end of the range
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_INVALID_RANGE - if either the start or end are 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 void remove (int start, int end) {
	checkWidget ();
	if (start > end) return;
	int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	if (!(0 <= start && start <= end && end < count)) {
		error (SWT.ERROR_INVALID_RANGE);
	}
	if (start == 0 && end == count - 1) {
		removeAll ();
		return;
	}
	int topIndex = (int)OS.SendMessage (handle, OS.LB_GETTOPINDEX, 0, 0);
	RECT rect = null;
	long hDC = 0, oldFont = 0, newFont = 0;
	int newWidth = 0;
	if ((style & SWT.H_SCROLL) != 0) {
		rect = new RECT ();
		hDC = OS.GetDC (handle);
		newFont = OS.SendMessage (handle, OS.WM_GETFONT, 0, 0);
		if (newFont != 0) oldFont = OS.SelectObject (hDC, newFont);
	}
	int index = start;
	int flags = OS.DT_CALCRECT | OS.DT_SINGLELINE | OS.DT_NOPREFIX;
	while (index <= end) {
		char [] buffer = null;
		int length = 0;
		if ((style & SWT.H_SCROLL) != 0) {
			length = (int)OS.SendMessage (handle, OS.LB_GETTEXTLEN, start, 0);
			if (length == OS.LB_ERR) break;
			buffer = new char [length + 1];
			int result = (int)OS.SendMessage (handle, OS.LB_GETTEXT, start, buffer);
			if (result == OS.LB_ERR) break;
		}
		int result = (int)OS.SendMessage (handle, OS.LB_DELETESTRING, start, 0);
		if (result == OS.LB_ERR) break;
		if ((style & SWT.H_SCROLL) != 0) {
			OS.DrawText (hDC, buffer, length, rect, flags);
			newWidth = Math.max (newWidth, rect.right - rect.left);
		}
		index++;
	}
	if ((style & SWT.H_SCROLL) != 0) {
		if (newFont != 0) OS.SelectObject (hDC, oldFont);
		OS.ReleaseDC (handle, hDC);
		setScrollWidth (newWidth, false);
	}
	if (end < topIndex) {
		topIndex -= end - start + 1;
	}
	OS.SendMessage (handle, OS.LB_SETTOPINDEX, topIndex, 0);
	if (index <= end) error (SWT.ERROR_ITEM_NOT_REMOVED);
}

/**
 * Searches the receiver's list starting at the first item
 * until an item is found that is equal to the argument,
 * and removes that item from the list.
 *
 * @param string the item to remove
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the string is null</li>
 *    <li>ERROR_INVALID_ARGUMENT - if the string is not found in the list</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 remove (String string) {
	checkWidget ();
	if (string == null) error (SWT.ERROR_NULL_ARGUMENT);
	int index = indexOf (string, 0);
	if (index == -1) error (SWT.ERROR_INVALID_ARGUMENT);
	remove (index);
}

/**
 * Removes all of the items from 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 removeAll () {
	checkWidget ();
	OS.SendMessage (handle, OS.LB_RESETCONTENT, 0, 0);
	if ((style & SWT.H_SCROLL) != 0) {
		OS.SendMessage (handle, OS.LB_SETHORIZONTALEXTENT, 0, 0);
	}
}

/**
 * Removes the listener from the collection of listeners who will
 * be notified when the user changes the receiver's selection.
 *
 * @param listener the listener which should no longer 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) {
	checkWidget ();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (eventTable == null) return;
	eventTable.unhook (SWT.Selection, listener);
	eventTable.unhook (SWT.DefaultSelection,listener);
}

/**
 * Selects the items at the given zero-relative indices in the receiver.
 * The current selection is not cleared before the new items are selected.
 * <p>
 * If the item at a given index is not selected, it is selected.
 * If the item at a given index was already selected, it remains selected.
 * Indices that are out of range and duplicate indices are ignored.
 * If the receiver is single-select and multiple indices are specified,
 * then all indices are ignored.
 *
 * @param indices the array of indices for the items to select
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the array of indices 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 List#setSelection(int[])
 */
public void select (int [] indices) {
	checkWidget ();
	if (indices == null) error (SWT.ERROR_NULL_ARGUMENT);
	int length = indices.length;
	if (length == 0 || ((style & SWT.SINGLE) != 0 && length > 1)) return;
	select (indices, false);
}

void select (int [] indices, boolean scroll) {
	int i = 0;
	while (i < indices.length) {
		int index = indices [i];
		if (index != -1) {
			select (index, false);
		}
		i++;
	}
	if (scroll) showSelection ();
}

/**
 * Selects the item at the given zero-relative index in the receiver's
 * list.  If the item at the index was already selected, it remains
 * selected. Indices that are out of range are ignored.
 *
 * @param index the index of the item to select
 *
 * @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 select (int index) {
	checkWidget ();
	select (index, false);
}

void select (int index, boolean scroll) {
	if (index < 0) return;
	int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	if (index >= count) return;
	if (scroll) {
		if ((style & SWT.SINGLE) != 0) {
			OS.SendMessage (handle, OS.LB_SETCURSEL, index, 0);
		} else {
			OS.SendMessage (handle, OS.LB_SETSEL, 1, index);
		}
		return;
	}
	int topIndex = (int)OS.SendMessage (handle, OS.LB_GETTOPINDEX, 0, 0);
	RECT itemRect = new RECT (), selectedRect = null;
	OS.SendMessage (handle, OS.LB_GETITEMRECT, index, itemRect);
	boolean redraw = getDrawing () && OS.IsWindowVisible (handle);
	if (redraw) {
		OS.UpdateWindow (handle);
		OS.SendMessage (handle, OS.WM_SETREDRAW, 0, 0);
	}
	int focusIndex = -1;
	if ((style & SWT.SINGLE) != 0) {
		int oldIndex = (int)OS.SendMessage (handle, OS.LB_GETCURSEL, 0, 0);
		if (oldIndex != -1) {
			selectedRect = new RECT ();
			OS.SendMessage (handle, OS.LB_GETITEMRECT, oldIndex, selectedRect);
		}
		OS.SendMessage (handle, OS.LB_SETCURSEL, index, 0);
	} else {
		focusIndex = (int)OS.SendMessage (handle, OS.LB_GETCARETINDEX, 0, 0);
		OS.SendMessage (handle, OS.LB_SETSEL, 1, index);
	}
	if ((style & SWT.MULTI) != 0) {
		if (focusIndex != -1) {
			OS.SendMessage (handle, OS.LB_SETCARETINDEX, focusIndex, 0);
		}
	}
	OS.SendMessage (handle, OS.LB_SETTOPINDEX, topIndex, 0);
	if (redraw) {
		OS.SendMessage (handle, OS.WM_SETREDRAW, 1, 0);
		OS.ValidateRect (handle, null);
		OS.InvalidateRect (handle, itemRect, true);
		if (selectedRect != null) {
			OS.InvalidateRect (handle, selectedRect, true);
		}
	}
}

/**
 * Selects the items in the range specified by the given zero-relative
 * indices in the receiver. The range of indices is inclusive.
 * The current selection is not cleared before the new items are selected.
 * <p>
 * If an item in the given range is not selected, it is selected.
 * If an item in the given range was already selected, it remains selected.
 * Indices that are out of range are ignored and no items will be selected
 * if start is greater than end.
 * If the receiver is single-select and there is more than one item in the
 * given range, then all indices are ignored.
 *
 * @param start the start of the range
 * @param end the end of the range
 *
 * @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 List#setSelection(int,int)
 */
public void select (int start, int end) {
	checkWidget ();
	if (end < 0 || start > end || ((style & SWT.SINGLE) != 0 && start != end)) return;
	int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	if (count == 0 || start >= count) return;
	start = Math.max (0, start);
	end = Math.min (end, count - 1);
	if ((style & SWT.SINGLE) != 0) {
		select (start, false);
	} else {
		select (start, end, false);
	}
}

void select (int start, int end, boolean scroll) {
	/*
	* Note that when start = end, LB_SELITEMRANGEEX
	* deselects the item.
	*/
	if (start == end) {
		select (start, scroll);
		return;
	}
	OS.SendMessage (handle, OS.LB_SELITEMRANGEEX, start, end);
	if (scroll) showSelection ();
}

/**
 * Selects all of the items in the receiver.
 * <p>
 * If the receiver is single-select, do nothing.
 *
 * @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 selectAll () {
	checkWidget ();
	if ((style & SWT.SINGLE) != 0) return;
	OS.SendMessage (handle, OS.LB_SETSEL, 1, -1);
}

void setFocusIndex (int index) {
//	checkWidget ();
	int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	if (!(0 <= index && index < count)) return;
	OS.SendMessage (handle, OS.LB_SETCARETINDEX, index, 0);
}

@Override
public void setFont (Font font) {
	checkWidget ();
	super.setFont (font);
	if ((style & SWT.H_SCROLL) != 0) setScrollWidth ();
}

/**
 * Sets the text of the item in the receiver's list at the given
 * zero-relative index to the string argument.
 *
 * @param index the index for the item
 * @param string the new text for the item
 *
 * @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>
 *    <li>ERROR_NULL_ARGUMENT - if the string 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 setItem (int index, String string) {
	checkWidget ();
	if (string == null) error (SWT.ERROR_NULL_ARGUMENT);
	int topIndex = getTopIndex ();
	boolean isSelected = isSelected (index);
	remove (index);
	add (string, index);
	if (isSelected) select (index, false);
	setTopIndex (topIndex);
}

/**
 * Sets the receiver's items to be the given array of items.
 *
 * @param items the array of items
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the items array is null</li>
 *    <li>ERROR_INVALID_ARGUMENT - if an item in the items array 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 setItems (String... items) {
	checkWidget ();
	if (items == null) error (SWT.ERROR_NULL_ARGUMENT);
	for (String item : items) {
		if (item == null) error (SWT.ERROR_INVALID_ARGUMENT);
	}
	long oldProc = OS.GetWindowLongPtr (handle, OS.GWLP_WNDPROC);
	OS.SetWindowLongPtr (handle, OS.GWLP_WNDPROC, ListProc);
	boolean redraw = getDrawing () && OS.IsWindowVisible (handle);
	if (redraw) {
		OS.SendMessage (handle, OS.WM_SETREDRAW, 0, 0);
	}
	RECT rect = null;
	long hDC = 0, oldFont = 0, newFont = 0;
	int newWidth = 0;
	if ((style & SWT.H_SCROLL) != 0) {
		rect = new RECT ();
		hDC = OS.GetDC (handle);
		newFont = OS.SendMessage (handle, OS.WM_GETFONT, 0, 0);
		if (newFont != 0) oldFont = OS.SelectObject (hDC, newFont);
		OS.SendMessage (handle, OS.LB_SETHORIZONTALEXTENT, 0, 0);
	}
	int length = items.length;
	OS.SendMessage (handle, OS.LB_RESETCONTENT, 0, 0);
	OS.SendMessage (handle, OS.LB_INITSTORAGE, length, length * 32);
	int index = 0;
	int cp = getCodePage ();
	while (index < length) {
		String string = items [index];
		TCHAR buffer = new TCHAR (cp, string, true);
		int result = (int)OS.SendMessage (handle, OS.LB_ADDSTRING, 0, buffer);
		if (result == OS.LB_ERR || result == OS.LB_ERRSPACE) break;
		if ((style & SWT.H_SCROLL) != 0) {
			int flags = OS.DT_CALCRECT | OS.DT_SINGLELINE | OS.DT_NOPREFIX;
			OS.DrawText (hDC, buffer, -1, rect, flags);
			newWidth = Math.max (newWidth, rect.right - rect.left);
		}
		index++;
	}
	if ((style & SWT.H_SCROLL) != 0) {
		if (newFont != 0) OS.SelectObject (hDC, oldFont);
		OS.ReleaseDC (handle, hDC);
		OS.SendMessage (handle, OS.LB_SETHORIZONTALEXTENT, newWidth + INSET, 0);
	}
	if (redraw) {
		OS.SendMessage (handle, OS.WM_SETREDRAW, 1, 0);
		/*
		* This code is intentionally commented.  The window proc
		* for the list box implements WM_SETREDRAW to invalidate
		* and erase the widget.  This is undocumented behavior.
		* The commented code below shows what is actually happening
		* and reminds us that we are relying on this undocumented
		* behavior.
		*/
//		int flags = OS.RDW_ERASE | OS.RDW_FRAME | OS.RDW_INVALIDATE;
//		OS.RedrawWindow (handle, null, 0, flags);
	}
	OS.SetWindowLongPtr (handle, OS.GWLP_WNDPROC, oldProc);
	if (index < items.length) error (SWT.ERROR_ITEM_NOT_ADDED);
}

/**
 * Calculates the scroll width depending on the item with the highest width
 */
void setScrollWidth () {
	int newWidth = 0;
	RECT rect = new RECT ();
	long newFont, oldFont = 0;
	long hDC = OS.GetDC (handle);
	newFont = OS.SendMessage (handle, OS.WM_GETFONT, 0, 0);
	if (newFont != 0) oldFont = OS.SelectObject (hDC, newFont);
	int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	int flags = OS.DT_CALCRECT | OS.DT_SINGLELINE | OS.DT_NOPREFIX;
	for (int i=0; i<count; i++) {
		int length = (int)OS.SendMessage (handle, OS.LB_GETTEXTLEN, i, 0);
		if (length != OS.LB_ERR) {
			char [] buffer = new char [length + 1];
			int result = (int)OS.SendMessage (handle, OS.LB_GETTEXT, i, buffer);
			if (result != OS.LB_ERR) {
				OS.DrawText (hDC, buffer, length, rect, flags);
				newWidth = Math.max (newWidth, rect.right - rect.left);
			}
		}
	}
	if (newFont != 0) OS.SelectObject (hDC, oldFont);
	OS.ReleaseDC (handle, hDC);
	OS.SendMessage (handle, OS.LB_SETHORIZONTALEXTENT, newWidth + INSET, 0);
}

void setScrollWidth (char[] buffer, boolean grow) {
	RECT rect = new RECT ();
	long newFont, oldFont = 0;
	long hDC = OS.GetDC (handle);
	newFont = OS.SendMessage (handle, OS.WM_GETFONT, 0, 0);
	if (newFont != 0) oldFont = OS.SelectObject (hDC, newFont);
	int flags = OS.DT_CALCRECT | OS.DT_SINGLELINE | OS.DT_NOPREFIX;
	OS.DrawText (hDC, buffer, -1, rect, flags);
	if (newFont != 0) OS.SelectObject (hDC, oldFont);
	OS.ReleaseDC (handle, hDC);
	setScrollWidth (rect.right - rect.left, grow);
}

void setScrollWidth (int newWidth, boolean grow) {
	newWidth += INSET;
	int width = (int)OS.SendMessage (handle, OS.LB_GETHORIZONTALEXTENT, 0, 0);
	if (grow) {
		if (newWidth <= width) return;
		OS.SendMessage (handle, OS.LB_SETHORIZONTALEXTENT, newWidth, 0);
	} else {
		if (newWidth < width) return;
		setScrollWidth ();
	}
}

/**
 * Selects the items at the given zero-relative indices in the receiver.
 * The current selection is cleared before the new items are selected,
 * and if necessary the receiver is scrolled to make the new selection visible.
 * <p>
 * Indices that are out of range and duplicate indices are ignored.
 * If the receiver is single-select and multiple indices are specified,
 * then all indices are ignored.
 *
 * @param indices the indices of the items to select
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the array of indices 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 List#deselectAll()
 * @see List#select(int[])
 */
public void setSelection(int [] indices) {
	checkWidget ();
	if (indices == null) error (SWT.ERROR_NULL_ARGUMENT);
	deselectAll ();
	int length = indices.length;
	if (length == 0 || ((style & SWT.SINGLE) != 0 && length > 1)) return;
	select (indices, true);
	if ((style & SWT.MULTI) != 0) {
		int focusIndex = indices [0];
		if (focusIndex >= 0) setFocusIndex (focusIndex);
	}
}

/**
 * Sets the receiver's selection to be the given array of items.
 * The current selection is cleared before the new items are selected,
 * and if necessary the receiver is scrolled to make the new selection visible.
 * <p>
 * Items that are not in the receiver are ignored.
 * If the receiver is single-select and multiple items are specified,
 * then all items are ignored.
 *
 * @param items the array of items
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the array of items 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 List#deselectAll()
 * @see List#select(int[])
 * @see List#setSelection(int[])
 */
public void setSelection (String [] items) {
	checkWidget ();
	if (items == null) error (SWT.ERROR_NULL_ARGUMENT);
	deselectAll ();
	int length = items.length;
	if (length == 0 || ((style & SWT.SINGLE) != 0 && length > 1)) return;
	int focusIndex = -1;
	for (int i=length-1; i>=0; --i) {
		String string = items [i];
		int index = 0;
		if (string != null) {
			int localFocus = -1;
			while ((index = indexOf (string, index)) != -1) {
				if (localFocus == -1) localFocus = index;
				select (index, false);
				if ((style & SWT.SINGLE) != 0 && isSelected (index)) {
					showSelection ();
					return;
				}
				index++;
			}
			if (localFocus != -1) focusIndex = localFocus;
		}
	}
	if ((style & SWT.MULTI) != 0) {
		if (focusIndex >= 0) setFocusIndex (focusIndex);
	}
}

/**
 * Selects the item at the given zero-relative index in the receiver.
 * If the item at the index was already selected, it remains selected.
 * The current selection is first cleared, then the new item is selected,
 * and if necessary the receiver is scrolled to make the new selection visible.
 * Indices that are out of range are ignored.
 *
 * @param index the index of the item to select
 *
 * @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 List#deselectAll()
 * @see List#select(int)
 */
public void setSelection (int index) {
	checkWidget ();
	deselectAll ();
	select (index, true);
	if ((style & SWT.MULTI) != 0) {
		if (index >= 0) setFocusIndex (index);
	}
}

/**
 * Selects the items in the range specified by the given zero-relative
 * indices in the receiver. The range of indices is inclusive.
 * The current selection is cleared before the new items are selected,
 * and if necessary the receiver is scrolled to make the new selection visible.
 * <p>
 * Indices that are out of range are ignored and no items will be selected
 * if start is greater than end.
 * If the receiver is single-select and there is more than one item in the
 * given range, then all indices are ignored.
 *
 * @param start the start index of the items to select
 * @param end the end index of the items to select
 *
 * @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 List#deselectAll()
 * @see List#select(int,int)
 */
public void setSelection (int start, int end) {
	checkWidget ();
	deselectAll ();
	if (end < 0 || start > end || ((style & SWT.SINGLE) != 0 && start != end)) return;
	int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	if (count == 0 || start >= count) return;
	start = Math.max (0, start);
	end = Math.min (end, count - 1);
	if ((style & SWT.SINGLE) != 0) {
		select (start, true);
	} else {
		select (start, end, true);
		setFocusIndex (start);
	}
}

/**
 * Sets the zero-relative index of the item which is currently
 * at the top of the receiver. This index can change when items
 * are scrolled or new items are added and removed.
 *
 * @param index the index of the top item
 *
 * @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 setTopIndex (int index) {
	checkWidget ();
	int result = (int)OS.SendMessage (handle, OS.LB_SETTOPINDEX, index, 0);
	if (result == OS.LB_ERR) {
		int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
		index = Math.min (count - 1, Math.max (0, index));
		OS.SendMessage (handle, OS.LB_SETTOPINDEX, index, 0);
	}
}

/**
 * Shows the selection.  If the selection is already showing in the receiver,
 * this method simply returns.  Otherwise, the items are scrolled until
 * the selection is visible.
 *
 * @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 showSelection () {
	checkWidget ();
	int index;
	if ((style & SWT.SINGLE) != 0) {
		index = (int)OS.SendMessage (handle, OS.LB_GETCURSEL, 0, 0);
	} else {
		int [] indices = new int [1];
		int result = (int)OS.SendMessage (handle, OS.LB_GETSELITEMS, 1, indices);
		index = indices [0];
		if (result != 1) index = -1;
	}
	if (index == -1) return;
	int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	if (count == 0) return;
	int height = (int)OS.SendMessage (handle, OS.LB_GETITEMHEIGHT, 0, 0);
	forceResize ();
	RECT rect = new RECT ();
	OS.GetClientRect (handle, rect);
	int topIndex = (int)OS.SendMessage (handle, OS.LB_GETTOPINDEX, 0, 0);
	int visibleCount = Math.max (rect.bottom / height, 1);
	int bottomIndex = Math.min (topIndex + visibleCount, count) - 1;
	if (topIndex <= index && index <= bottomIndex) return;
	int newTop = Math.min (Math.max (index - (visibleCount / 2), 0), count - 1);
	OS.SendMessage (handle, OS.LB_SETTOPINDEX, newTop, 0);
}

@Override
void updateMenuLocation (Event event) {
	Rectangle clientArea = getClientAreaInPixels ();
	int x = clientArea.x, y = clientArea.y;
	int focusIndex = getFocusIndex();
	if (focusIndex != -1) {
		RECT rect = new RECT ();
		long newFont, oldFont = 0;
		long hDC = OS.GetDC (handle);
		newFont = OS.SendMessage (handle, OS.WM_GETFONT, 0, 0);
		if (newFont != 0) oldFont = OS.SelectObject (hDC, newFont);
		int flags = OS.DT_CALCRECT | OS.DT_SINGLELINE | OS.DT_NOPREFIX;
		char [] buffer = new char [64 + 1];
		int length = (int)OS.SendMessage (handle, OS.LB_GETTEXTLEN, focusIndex, 0);
		if (length != OS.LB_ERR) {
			if (length + 1 > buffer.length) {
				buffer = new char [length + 1];
			}
			int result = (int)OS.SendMessage (handle, OS.LB_GETTEXT, focusIndex, buffer);
			if (result != OS.LB_ERR) {
				OS.DrawText (hDC, buffer, length, rect, flags);
			}
		}
		if (newFont != 0) OS.SelectObject (hDC, oldFont);
		OS.ReleaseDC (handle, hDC);
		x = Math.max (x, rect.right / 2);
		x = Math.min (x, clientArea.x + clientArea.width);

		OS.SendMessage (handle, OS.LB_GETITEMRECT, focusIndex, rect);
		y = Math.max (y, rect.bottom);
		y = Math.min (y, clientArea.y + clientArea.height);
	}
	Point pt = toDisplayInPixels (x, y);
	int zoom = getAutoscalingZoom();
	event.setLocation(DPIUtil.pixelToPoint(pt.x, zoom), DPIUtil.pixelToPoint(pt.y, zoom));
}

@Override
boolean updateTextDirection (int textDirection) {
	if (textDirection == AUTO_TEXT_DIRECTION) {
		/* If auto is already in effect, there's nothing to do. */
		if ((state & HAS_AUTO_DIRECTION) != 0) return false;
		state |= HAS_AUTO_DIRECTION;
	} else {
		state &= ~HAS_AUTO_DIRECTION;
		if (!addedUCC /*(state & HAS_AUTO_DIRECTION) == 0*/) {
			return super.updateTextDirection (textDirection);
		}
	}
	int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
	if (count == OS.LB_ERR) return false;
	int selection = (int)OS.SendMessage (handle, OS.LB_GETCURSEL, 0, 0);
	addedUCC = false;
	while (count-- > 0) {
		int length = (int)OS.SendMessage (handle, OS.LB_GETTEXTLEN, count, 0);
		if (length == OS.LB_ERR) break;
		if (length == 0) continue;
		char [] buffer = new char [length + 1];
		if (OS.SendMessage (handle, OS.LB_GETTEXT, count, buffer) == OS.LB_ERR) break;
		if (OS.SendMessage (handle, OS.LB_DELETESTRING, count, 0) == OS.LB_ERR) break;
		if ((state & HAS_AUTO_DIRECTION) == 0) {
			/* Should remove UCC */
			System.arraycopy(buffer, 1, buffer, 0, length);
		}
		/* Adding UCC is handled in OS.LB_INSERTSTRING */
		if (OS.SendMessage (handle, OS.LB_INSERTSTRING, count, buffer) == OS.LB_ERR) break;
	}
	if (selection != OS.LB_ERR) {
		OS.SendMessage (handle, OS.LB_SETCURSEL, selection, 0);
	}
	return textDirection == AUTO_TEXT_DIRECTION || super.updateTextDirection (textDirection);
}

@Override
int widgetStyle () {
	int bits = super.widgetStyle () | OS.LBS_NOTIFY | OS.LBS_NOINTEGRALHEIGHT;
	if ((style & SWT.SINGLE) != 0) return bits;
	if ((style & SWT.MULTI) != 0) {
		if ((style & SWT.SIMPLE) != 0) return bits | OS.LBS_MULTIPLESEL;
		return bits | OS.LBS_EXTENDEDSEL;
	}
	return bits;
}

@Override
TCHAR windowClass () {
	return ListClass;
}

@Override
long windowProc () {
	return ListProc;
}

@Override
long windowProc (long hwnd, int msg, long wParam, long lParam) {
	/* Below code is to support auto text direction. */
	if (handle != 0 && lParam != 0 && (state & HAS_AUTO_DIRECTION) != 0) {
		switch (msg) {
			case OS.LB_ADDSTRING:
			case OS.LB_INSERTSTRING:
			case OS.LB_FINDSTRINGEXACT:
				int length = OS.wcslen (lParam); // we are always Unicode here
				int cp = getCodePage ();
				TCHAR buffer = new TCHAR (cp, length);
				OS.MoveMemory (buffer, lParam, buffer.length () * TCHAR.sizeof);
				String string = buffer.toString (0, length);
				int direction = BidiUtil.resolveTextDirection (string);
				if (direction == SWT.NONE) {
					/*
					 * Force adding a UCC even when no strong characters are found.
					 * Otherwise, the List items would retain the old direction,
					 * which might be inappropriate for the new text.
					 */
					direction = (style & SWT.RIGHT_TO_LEFT) != 0 ? SWT.RIGHT_TO_LEFT : SWT.LEFT_TO_RIGHT;
				}
				string = (direction == SWT.RIGHT_TO_LEFT ? RLE : LRE) + string;
				buffer = new TCHAR (cp, string, true);
				long hHeap = OS.GetProcessHeap ();
				length = buffer.length() * TCHAR.sizeof;
				long pszText = OS.HeapAlloc (hHeap, OS.HEAP_ZERO_MEMORY, length);
				OS.MoveMemory (pszText, buffer, length);
				long code = super.windowProc (hwnd, msg, wParam, pszText);
				OS.HeapFree (hHeap, 0, pszText);
				addedUCC = true;
				return code;
		}
	}
	return super.windowProc (hwnd, msg, wParam, lParam);
}

@Override
LRESULT WM_CHAR (long wParam, long lParam) {
	LRESULT result = super.WM_CHAR (wParam, lParam);
	if (result != null) return result;
	/*
	* Feature in Windows.  The Windows list box does not implement
	* the control key interface for multi-select list boxes, making
	* it inaccessible from the keyboard.  The fix is to implement
	* the key processing.
	*/
	if (OS.GetKeyState (OS.VK_CONTROL) < 0 && OS.GetKeyState (OS.VK_SHIFT) >= 0) {
		int bits = OS.GetWindowLong (handle, OS.GWL_STYLE);
		if ((bits & OS.LBS_EXTENDEDSEL) != 0) {
			switch ((int)wParam) {
				case OS.VK_SPACE: {
					int index = (int)OS.SendMessage (handle, OS.LB_GETCARETINDEX, 0, 0);
					int code = (int)OS.SendMessage (handle, OS.LB_GETSEL, index, 0);
					if (code == OS.LB_ERR) break;
					OS.SendMessage (handle, OS.LB_SETSEL, code != 0 ? 0 : 1, index);
					OS.SendMessage (handle, OS.LB_SETANCHORINDEX, index, 0);
					sendSelectionEvent (SWT.Selection);
					return LRESULT.ZERO;
				}
			}
		}
	}
	return result;
}

@Override
LRESULT WM_KEYDOWN (long wParam, long lParam) {
	LRESULT result = super.WM_KEYDOWN (wParam, lParam);
	if (result != null) return result;
	/*
	* Feature in Windows.  The Windows list box does not implement
	* the control key interface for multi-select list boxes, making
	* it inaccessible from the keyboard.  The fix is to implement
	* the key processing.
	*/
	if (OS.GetKeyState (OS.VK_CONTROL) < 0 && OS.GetKeyState (OS.VK_SHIFT) >= 0) {
		int bits = OS.GetWindowLong (handle, OS.GWL_STYLE);
		if ((bits & OS.LBS_EXTENDEDSEL) != 0) {
			int newIndex = -1;
			switch ((int)wParam) {
				case OS.VK_SPACE: {
					/*
					* Ensure that the window proc does not process VK_SPACE
					* so that it can be handled in WM_CHAR.  This allows the
					* application to cancel an operation that is normally
					* performed in WM_KEYDOWN from WM_CHAR.
					*/
					return LRESULT.ZERO;
				}
				case OS.VK_UP:
				case OS.VK_DOWN: {
					int oldIndex = (int)OS.SendMessage (handle, OS.LB_GETCARETINDEX, 0, 0);
					newIndex = Math.max (0, oldIndex + (((int)wParam) == OS.VK_UP ? -1 : 1));
					break;
				}
				case OS.VK_PRIOR: {
					int topIndex = (int)OS.SendMessage (handle, OS.LB_GETTOPINDEX, 0, 0);
					int oldIndex = (int)OS.SendMessage (handle, OS.LB_GETCARETINDEX, 0, 0);
					if (oldIndex != topIndex) {
						newIndex = topIndex;
					} else {
						forceResize ();
						RECT rect = new RECT ();
						OS.GetClientRect (handle, rect);
						int itemHeight = (int)OS.SendMessage (handle, OS.LB_GETITEMHEIGHT, 0, 0);
						int pageSize = Math.max (2, (rect.bottom / itemHeight));
						newIndex = Math.max (0, topIndex - (pageSize - 1));
					}
					break;
				}
				case OS.VK_NEXT: {
					int topIndex = (int)OS.SendMessage (handle, OS.LB_GETTOPINDEX, 0, 0);
					int oldIndex = (int)OS.SendMessage (handle, OS.LB_GETCARETINDEX, 0, 0);
					forceResize ();
					RECT rect = new RECT ();
					OS.GetClientRect (handle, rect);
					int itemHeight = (int)OS.SendMessage (handle, OS.LB_GETITEMHEIGHT, 0, 0);
					int pageSize = Math.max (2, (rect.bottom / itemHeight));
					int bottomIndex = topIndex + pageSize - 1;
					if (oldIndex != bottomIndex) {
						newIndex = bottomIndex;
					} else {
						newIndex = bottomIndex + pageSize - 1;
					}
					int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
					if (count != OS.LB_ERR) newIndex = Math.min (count - 1, newIndex);
					break;
				}
				case OS.VK_HOME: {
					newIndex = 0;
					break;
				}
				case OS.VK_END: {
					int count = (int)OS.SendMessage (handle, OS.LB_GETCOUNT, 0, 0);
					if (count == OS.LB_ERR) break;
					newIndex = count - 1;
					break;
				}
			}
			if (newIndex != -1) {
				/*
				* Feature in Windows.  When the user changes focus using
				* the keyboard, the focus indicator does not draw.  The
				* fix is to update the UI state for the control whenever
				* the focus indicator changes as a result of something
				* the user types.
				*/
				int uiState = (int)OS.SendMessage (handle, OS.WM_QUERYUISTATE, 0, 0);
				if ((uiState & OS.UISF_HIDEFOCUS) != 0) {
					OS.SendMessage (handle, OS.WM_CHANGEUISTATE, OS.UIS_INITIALIZE, 0);
					/*
					* Bug in Windows.  When the WM_CHANGEUISTATE is used
					* to update the UI state for a list that has been
					* selected using Shift+Arrow, the focus indicator
					* has pixel corruption.  The fix is to redraw the
					* control.
					*/
					RECT itemRect = new RECT ();
					int oldIndex = (int)OS.SendMessage (handle, OS.LB_GETCARETINDEX, 0, 0);
					OS.SendMessage (handle, OS.LB_GETITEMRECT, oldIndex, itemRect);
					OS.InvalidateRect (handle, itemRect, true);
				}
				OS.SendMessage (handle, OS.LB_SETCARETINDEX, newIndex, 0);
				return LRESULT.ZERO;
			}
		}
	}
	return result;
}

@Override
LRESULT WM_SETREDRAW (long wParam, long lParam) {
	LRESULT result = super.WM_SETREDRAW (wParam, lParam);
	if (result != null) return result;
	/*
	* Bug in Windows.  When WM_SETREDRAW is used to turn off
	* redraw for a list, table or tree, the background of the
	* control is drawn.  The fix is to call DefWindowProc(),
	* which stops all graphics output to the control.
	*/
	OS.DefWindowProc (handle, OS.WM_SETREDRAW, wParam, lParam);
	return result;
}

@Override
LRESULT WM_SIZE (long wParam, long lParam) {
	/*
	* Bug in Windows.  If the top index is changed while the
	* list is being resized, Windows does not redraw properly
	* when their is white space at the bottom of the control.
	* The fix is to detect when the top index has changed and
	* redraw the control.
	*
	* Bug in Windows.  If the receiver is scrolled horizontally
	* and is resized, the list does not redraw properly.  The fix
	* is to redraw the control when the horizontal scroll bar is
	* not at the beginning.
	*/
	int oldIndex = (int)OS.SendMessage (handle, OS.LB_GETTOPINDEX, 0, 0);
	LRESULT result = super.WM_SIZE (wParam, lParam);
	if (!isDisposed ()) {
		SCROLLINFO info = new SCROLLINFO ();
		info.cbSize = SCROLLINFO.sizeof;
		info.fMask = OS.SIF_POS;
		if (OS.GetScrollInfo (handle, OS.SB_HORZ, info)) {
			if (info.nPos != 0) OS.InvalidateRect (handle, null, true);
		}
		int newIndex = (int)OS.SendMessage (handle, OS.LB_GETTOPINDEX, 0, 0);
		if (oldIndex != newIndex) OS.InvalidateRect (handle, null, true);
	}
	return result;
}

@Override
LRESULT wmCommandChild (long wParam, long lParam) {
	int code = OS.HIWORD (wParam);
	switch (code) {
		case OS.LBN_SELCHANGE:
			sendSelectionEvent (SWT.Selection);
			break;
		case OS.LBN_DBLCLK:
			sendSelectionEvent (SWT.DefaultSelection);
			break;
	}
	return super.wmCommandChild (wParam, lParam);
}

@Override
void handleDPIChange(Event event, float scalingFactor) {
	super.handleDPIChange(event, scalingFactor);
	if((style & SWT.H_SCROLL) != 0) {
		// Recalculate the Scroll width, as length of items has changed
		setScrollWidth();
	}
}
}
