path: root/bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/Label.java

/*******************************************************************************
 * Copyright (c) 2000, 2011 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.widgets;


import org.eclipse.swt.internal.win32.*;
import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;

/**
 * Instances of this class represent a non-selectable
 * user interface object that displays a string or image.
 * When SEPARATOR is specified, displays a single
 * vertical or horizontal line.
 * <p>
 * Shadow styles are hints and may not be honored
 * by the platform.  To create a separator label
 * with the default shadow style for the platform,
 * do not specify a shadow style.
 * </p>
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>SEPARATOR, HORIZONTAL, VERTICAL</dd>
 * <dd>SHADOW_IN, SHADOW_OUT, SHADOW_NONE</dd>
 * <dd>CENTER, LEFT, RIGHT, WRAP</dd>
 * <dt><b>Events:</b></dt>
 * <dd>(none)</dd>
 * </dl>
 * <p>
 * Note: Only one of SHADOW_IN, SHADOW_OUT and SHADOW_NONE may be specified.
 * SHADOW_NONE is a HINT. Only one of HORIZONTAL and VERTICAL may be specified.
 * Only one of CENTER, LEFT and RIGHT 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/#label">Label 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 Label extends Control {
	String text = "";
	Image image;
	static final int MARGIN = 4;
	static /*final*/ boolean IMAGE_AND_TEXT = true;
	static final int /*long*/ LabelProc;
	static final TCHAR LabelClass = new TCHAR (0, "STATIC", true);
	static {
		WNDCLASS lpWndClass = new WNDCLASS ();
		OS.GetClassInfo (0, LabelClass, lpWndClass);
		LabelProc = 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#SEPARATOR
 * @see SWT#HORIZONTAL
 * @see SWT#VERTICAL
 * @see SWT#SHADOW_IN
 * @see SWT#SHADOW_OUT
 * @see SWT#SHADOW_NONE
 * @see SWT#CENTER
 * @see SWT#LEFT
 * @see SWT#RIGHT
 * @see SWT#WRAP
 * @see Widget#checkSubclass
 * @see Widget#getStyle
 */
public Label (Composite parent, int style) {
	super (parent, checkStyle (style));
}

int /*long*/ callWindowProc (int /*long*/ hwnd, int msg, int /*long*/ wParam, int /*long*/ lParam) {
	if (handle == 0) return 0;
	/*
	* Feature in Windows 7.  When the user double clicks 
	* on the label, the text of the label is copied to the 
	* clipboard.  This is unwanted. The fix is to avoid 
	* calling the label window proc.
	*/
	if (!OS.IsWinCE && OS.WIN32_VERSION >= OS.VERSION(6, 1)) {
		switch (msg) {
			case OS.WM_LBUTTONDBLCLK: return OS.DefWindowProc (hwnd, msg, wParam, lParam);
		}
	}
	return OS.CallWindowProc (LabelProc, hwnd, msg, wParam, lParam);
}

static int checkStyle (int style) {
	style |= SWT.NO_FOCUS;
	if ((style & SWT.SEPARATOR) != 0) {
		style = checkBits (style, SWT.VERTICAL, SWT.HORIZONTAL, 0, 0, 0, 0);
		return checkBits (style, SWT.SHADOW_OUT, SWT.SHADOW_IN, SWT.SHADOW_NONE, 0, 0, 0);
	} 
	return checkBits (style, SWT.LEFT, SWT.CENTER, SWT.RIGHT, 0, 0, 0);
}

public Point computeSize (int wHint, int hHint, boolean changed) {
	checkWidget ();
	int width = 0, height = 0, border = getBorderWidth ();
	if ((style & SWT.SEPARATOR) != 0) {
		int lineWidth = OS.GetSystemMetrics (OS.SM_CXBORDER);
		if ((style & SWT.HORIZONTAL) != 0) {
			width = DEFAULT_WIDTH;  height = lineWidth * 2;
		} else {
			width = lineWidth * 2; height = DEFAULT_HEIGHT;
		}
		if (wHint != SWT.DEFAULT) width = wHint;
		if (hHint != SWT.DEFAULT) height = hHint;
		width += border * 2; height += border * 2;
		return new Point (width, height);
	}
	int bits = OS.GetWindowLong (handle, OS.GWL_STYLE);
	boolean drawText = true;
	boolean drawImage = (bits & OS.SS_OWNERDRAW) == OS.SS_OWNERDRAW;
	if (drawImage) {
		if (image != null) {
			Rectangle rect = image.getBounds();
			width += rect.width;
			height += rect.height;
			if (IMAGE_AND_TEXT) {
				if (text.length () != 0) width += MARGIN;
			} else {
				drawText = false;
			}
		}
	}
	if (drawText) {
		int /*long*/ hDC = OS.GetDC (handle);
		int /*long*/ newFont = OS.SendMessage (handle, OS.WM_GETFONT, 0, 0);
		int /*long*/ oldFont = OS.SelectObject (hDC, newFont);
		int length = OS.GetWindowTextLength (handle);
		if (length == 0) {
			TEXTMETRIC tm = OS.IsUnicode ? (TEXTMETRIC) new TEXTMETRICW () : new TEXTMETRICA ();
			OS.GetTextMetrics (hDC, tm);
			height = Math.max (height, tm.tmHeight);
		} else {
			RECT rect = new RECT ();
			int flags = OS.DT_CALCRECT | OS.DT_EDITCONTROL | OS.DT_EXPANDTABS;
			if ((style & SWT.WRAP) != 0 && wHint != SWT.DEFAULT) {
				flags |= OS.DT_WORDBREAK;
				rect.right = Math.max (0, wHint - width);
			}
			TCHAR buffer = new TCHAR (getCodePage (), length + 1);
			OS.GetWindowText (handle, buffer, length + 1);
			OS.DrawText (hDC, buffer, length, rect, flags);
			width += rect.right - rect.left;
			height = Math.max (height, rect.bottom - rect.top);
		}
		if (newFont != 0) OS.SelectObject (hDC, oldFont);
		OS.ReleaseDC (handle, hDC);
	}
	if (wHint != SWT.DEFAULT) width = wHint;
	if (hHint != SWT.DEFAULT) height = hHint;
	width += border * 2;
	height += border * 2;
	/* 
	* Feature in WinCE PPC.  Text labels have a trim
	* of one pixel wide on the right and left side.
	* The fix is to increase the width to include
	* this trim.
	*/
	if (OS.IsWinCE && !drawImage) width += 2;
	return new Point (width, height);
}

void createHandle () {
	super.createHandle ();
	state |= THEME_BACKGROUND;
}

/**
 * Returns a value which describes the position of the
 * text or image in the receiver. The value will be one of
 * <code>LEFT</code>, <code>RIGHT</code> or <code>CENTER</code>
 * unless the receiver is a <code>SEPARATOR</code> label, in 
 * which case, <code>NONE</code> is returned.
 *
 * @return the alignment 
 *
 * @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 getAlignment () {
	checkWidget ();
	if ((style & SWT.SEPARATOR) != 0) return 0;
	if ((style & SWT.LEFT) != 0) return SWT.LEFT;
	if ((style & SWT.CENTER) != 0) return SWT.CENTER;
	if ((style & SWT.RIGHT) != 0) return SWT.RIGHT;
	return SWT.LEFT;
}

boolean getBufferredPaint() {
	Shell shell = getShell ();
	if ((shell.style & SWT.TRIM_FILL) != 0) {
		// if (image != null) return false;//note: can't be transparent for all images...
		return true;//bad: should be transparent with custom draw
	}
	return false;
}

/**
 * Returns the receiver's image if it has one, or null
 * if it does not.
 *
 * @return the receiver's image
 *
 * @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 Image getImage () {
	checkWidget ();
	return image;
}

String getNameText () {
	return getText ();
}

/**
 * Returns the receiver's text, which will be an empty
 * string if it has never been set or if the receiver is
 * a <code>SEPARATOR</code> label.
 *
 * @return the receiver's text
 *
 * @exception SWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 */
public String getText () {
	checkWidget ();
	if ((style & SWT.SEPARATOR) != 0) return "";
	return text;
}

boolean mnemonicHit (char key) {
	Composite control = this.parent;
	while (control != null) {
		Control [] children = control._getChildren ();
		int index = 0;
		while (index < children.length) {
			if (children [index] == this) break;
			index++;
		}
		index++;
		if (index < children.length) {
			if (children [index].setFocus ()) return true;
		}
		control = control.parent;
	}
	return false;
}

boolean mnemonicMatch (char key) {
	char mnemonic = findMnemonic (getText ());
	if (mnemonic == '\0') return false;
	return Character.toUpperCase (key) == Character.toUpperCase (mnemonic);
}

void releaseWidget () {
	super.releaseWidget ();
	text = null;
	image = null;
}

/**
 * Controls how text and images will be displayed in the receiver.
 * The argument should be one of <code>LEFT</code>, <code>RIGHT</code>
 * or <code>CENTER</code>.  If the receiver is a <code>SEPARATOR</code>
 * label, the argument is ignored and the alignment is not changed.
 *
 * @param alignment the new alignment 
 *
 * @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 setAlignment (int alignment) {
	checkWidget ();
	if ((style & SWT.SEPARATOR) != 0) return;
	if ((alignment & (SWT.LEFT | SWT.RIGHT | SWT.CENTER)) == 0) return;
	style &= ~(SWT.LEFT | SWT.RIGHT | SWT.CENTER);
	style |= alignment & (SWT.LEFT | SWT.RIGHT | SWT.CENTER);
	int bits = OS.GetWindowLong (handle, OS.GWL_STYLE);
	if ((bits & OS.SS_OWNERDRAW) != OS.SS_OWNERDRAW) {
		bits &= ~(OS.SS_LEFTNOWORDWRAP | OS.SS_CENTER | OS.SS_RIGHT);
		if ((style & SWT.LEFT) != 0) {
			if ((style & SWT.WRAP) != 0) {
				bits |= OS.SS_LEFT;
			} else {
				bits |= OS.SS_LEFTNOWORDWRAP;
			}
		}
		if ((style & SWT.CENTER) != 0) bits |= OS.SS_CENTER;
		if ((style & SWT.RIGHT) != 0) bits |= OS.SS_RIGHT;
		OS.SetWindowLong (handle, OS.GWL_STYLE, bits);
	}
	OS.InvalidateRect (handle, null, true);
}

/**
 * Sets the receiver's image to the argument, which may be
 * null indicating that no image should be displayed.
 *
 * @param image the image to display on the receiver (may be null)
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_INVALID_ARGUMENT - if the image has been disposed</li> 
 * </ul>
 * @exception SWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 */
public void setImage (Image image) {
	checkWidget ();
	if ((style & SWT.SEPARATOR) != 0) return;
	if (image != null && image.isDisposed()) error(SWT.ERROR_INVALID_ARGUMENT);
	this.image = image;
	int bits = OS.GetWindowLong (handle, OS.GWL_STYLE);
	if ((bits & OS.SS_OWNERDRAW) != OS.SS_OWNERDRAW) {
		bits &= ~(OS.SS_LEFTNOWORDWRAP | OS.SS_CENTER | OS.SS_RIGHT);
		bits |= OS.SS_OWNERDRAW;
		OS.SetWindowLong (handle, OS.GWL_STYLE, bits);
	}
	OS.InvalidateRect (handle, null, true);
}

/**
 * Sets the receiver's text.
 * <p>
 * This method sets the widget label.  The label may include
 * the mnemonic character and line delimiters.
 * </p>
 * <p>
 * Mnemonics are indicated by an '&amp;' that causes the next
 * character to be the mnemonic.  When the user presses a
 * key sequence that matches the mnemonic, focus is assigned
 * to the control that follows the label. On most platforms,
 * the mnemonic appears underlined but may be emphasised in a
 * platform specific manner.  The mnemonic indicator character
 * '&amp;' can be escaped by doubling it in the string, causing
 * a single '&amp;' to be displayed.
 * </p>
 * 
 * @param string the new text
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the text 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 setText (String string) {
	checkWidget ();
	if (string == null) error (SWT.ERROR_NULL_ARGUMENT);
	if ((style & SWT.SEPARATOR) != 0) return;
	/*
	* Feature in Windows.  For some reason, SetWindowText() for
	* static controls redraws the control, even when the text has
	* has not changed.  The fix is to check for this case and do
	* nothing.
	*/
	if (string.equals (text)) return;
	text = string;
	if (image == null || !IMAGE_AND_TEXT) {
		int oldBits = OS.GetWindowLong (handle, OS.GWL_STYLE), newBits = oldBits;
		newBits &= ~OS.SS_OWNERDRAW;
		if ((style & SWT.LEFT) != 0) {
			if ((style & SWT.WRAP) != 0) {
				newBits |= OS.SS_LEFT;
			} else {
				newBits |= OS.SS_LEFTNOWORDWRAP;
			}
		}
		if ((style & SWT.CENTER) != 0) newBits |= OS.SS_CENTER;
		if ((style & SWT.RIGHT) != 0) newBits |= OS.SS_RIGHT;
		if (oldBits != newBits) OS.SetWindowLong (handle, OS.GWL_STYLE, newBits);
	}
	string = Display.withCrLf (string);
	TCHAR buffer = new TCHAR (getCodePage (), string, true);
	OS.SetWindowText (handle, buffer);
	/*
	* Bug in Windows.  For some reason, the HBRUSH that
	* is returned from WM_CTRLCOLOR is misaligned when
	* the label uses it to draw.  If the brush is a solid
	* color, this does not matter.  However, if the brush
	* contains an image, the image is misaligned.  The
	* fix is to draw the background in WM_ERASEBKGND.
	*/
	if (OS.COMCTL32_MAJOR < 6) {
		if (findImageControl () != null) OS.InvalidateRect (handle, null, true);
	}
}

int widgetExtStyle () {
	int bits = super.widgetExtStyle () & ~OS.WS_EX_CLIENTEDGE;
	if ((style & SWT.BORDER) != 0) return bits | OS.WS_EX_STATICEDGE;
	return bits;
}

int widgetStyle () {
	int bits = super.widgetStyle () | OS.SS_NOTIFY;
	if ((style & SWT.SEPARATOR) != 0) return bits | OS.SS_OWNERDRAW;
	if (OS.WIN32_VERSION >= OS.VERSION (5, 0)) {
		if ((style & SWT.WRAP) != 0) bits |= OS.SS_EDITCONTROL;
	} 
	if ((style & SWT.CENTER) != 0) return bits | OS.SS_CENTER;
	if ((style & SWT.RIGHT) != 0) return bits | OS.SS_RIGHT;
	if ((style & SWT.WRAP) != 0) return bits | OS.SS_LEFT;
	return bits | OS.SS_LEFTNOWORDWRAP;
}

TCHAR windowClass () {
	return LabelClass;
}

int /*long*/ windowProc () {
	return LabelProc;
}

LRESULT WM_ERASEBKGND (int /*long*/ wParam, int /*long*/ lParam) {
	LRESULT result = super.WM_ERASEBKGND (wParam, lParam);
	if (result != null) return result;
	int bits = OS.GetWindowLong (handle, OS.GWL_STYLE);
	if ((bits & OS.SS_OWNERDRAW) == OS.SS_OWNERDRAW) {
		return LRESULT.ONE;
	}
	/*
	* Bug in Windows.  For some reason, the HBRUSH that
	* is returned from WM_CTRLCOLOR is misaligned when
	* the label uses it to draw.  If the brush is a solid
	* color, this does not matter.  However, if the brush
	* contains an image, the image is misaligned.  The
	* fix is to draw the background in WM_ERASEBKGND.
	*/
	if (OS.COMCTL32_MAJOR < 6) {
		if (findImageControl () != null) {
			drawBackground (wParam);
			return LRESULT.ONE;
		}
	}
	return result;
}

LRESULT WM_SIZE (int /*long*/ wParam, int /*long*/ lParam) {
	LRESULT result = super.WM_SIZE (wParam, lParam);
	if (isDisposed ()) return result;
	if ((style & SWT.SEPARATOR) != 0) {
		OS.InvalidateRect (handle, null, true);
		return result;
	}
	int bits = OS.GetWindowLong (handle, OS.GWL_STYLE);
	if ((bits & OS.SS_OWNERDRAW) == OS.SS_OWNERDRAW) {
		OS.InvalidateRect (handle, null, true);
		return result;
	}
	/*
	* Bug in Windows.  For some reason, a label with
	* style SS_LEFT, SS_CENTER or SS_RIGHT does not
	* redraw the text in the new position when resized.
	* Note that SS_LEFTNOWORDWRAP does not have the
	* problem.  The fix is to force the redraw.
	*/
	if ((bits & OS.SS_LEFTNOWORDWRAP) != OS.SS_LEFTNOWORDWRAP) {
		OS.InvalidateRect (handle, null, true);
		return result;
	}
	return result;
}

LRESULT WM_UPDATEUISTATE (int /*long*/ wParam, int /*long*/ lParam) {
	LRESULT result = super.WM_UPDATEUISTATE (wParam, lParam);
	if (result != null) return result;
	/*
	* Feature in Windows.  When WM_UPDATEUISTATE is sent to
	* a static control, it sends WM_CTLCOLORSTATIC to get the
	* foreground and background.  If any drawing happens in
	* WM_CTLCOLORSTATIC, it overwrites the contents of the control.
	* The fix is draw the static without drawing the background
	* and avoid the static window proc.
	*/
	boolean redraw = findImageControl () != null;
	if (!redraw) {
		if ((state & THEME_BACKGROUND) != 0) {
			if (OS.COMCTL32_MAJOR >= 6 && OS.IsAppThemed ()) {
				redraw = findThemeControl () != null;
			}
		}
	}
	if (redraw) {
		OS.InvalidateRect (handle, null, false);
		int /*long*/ code = OS.DefWindowProc (handle, OS.WM_UPDATEUISTATE, wParam, lParam);
		return new LRESULT (code);
	}
	return result;
}

LRESULT wmColorChild (int /*long*/ wParam, int /*long*/ lParam) {
	/*
	* Bug in Windows.  For some reason, the HBRUSH that
	* is returned from WM_CTRLCOLOR is misaligned when
	* the label uses it to draw.  If the brush is a solid
	* color, this does not matter.  However, if the brush
	* contains an image, the image is misaligned.  The
	* fix is to draw the background in WM_ERASEBKGND.
	*/
	LRESULT result = super.wmColorChild (wParam, lParam);
	if (OS.COMCTL32_MAJOR < 6) {
		int bits = OS.GetWindowLong (handle, OS.GWL_STYLE);
		if ((bits & OS.SS_OWNERDRAW) != OS.SS_OWNERDRAW) {
			if (findImageControl () != null) {
				OS.SetBkMode (wParam, OS.TRANSPARENT);
				return new LRESULT (OS.GetStockObject (OS.NULL_BRUSH));
			}
		}
	}
	return result;
}

LRESULT WM_PAINT (int /*long*/ wParam, int /*long*/ lParam) {
	if (OS.IsWinCE) {
		boolean drawImage = image != null;
		boolean drawSeparator = (style & SWT.SEPARATOR) != 0 && (style & SWT.SHADOW_NONE) == 0;
		if (drawImage || drawSeparator) {
			LRESULT result = null;
			PAINTSTRUCT ps = new PAINTSTRUCT ();
			GCData data = new GCData ();
			data.ps = ps;
			data.hwnd = handle;
			GC gc = new_GC (data);
			if (gc != null) {
				drawBackground (gc.handle);
				RECT clientRect = new RECT();
				OS.GetClientRect (handle, clientRect);
				if (drawSeparator) {
					RECT rect = new RECT ();
					int lineWidth = OS.GetSystemMetrics (OS.SM_CXBORDER);
					int flags = (style & SWT.SHADOW_IN) != 0 ? OS.EDGE_SUNKEN : OS.EDGE_ETCHED;
					if ((style & SWT.HORIZONTAL) != 0) {
						int bottom = clientRect.top + Math.max (lineWidth * 2, (clientRect.bottom - clientRect.top) / 2);
						OS.SetRect (rect, clientRect.left, clientRect.top, clientRect.right, bottom);
						OS.DrawEdge (gc.handle, rect, flags, OS.BF_BOTTOM);
					} else {
						int right = clientRect.left + Math.max (lineWidth * 2, (clientRect.right - clientRect.left) / 2);
						OS.SetRect (rect, clientRect.left, clientRect.top, right, clientRect.bottom);
						OS.DrawEdge (gc.handle, rect, flags, OS.BF_RIGHT);
					}
					result = LRESULT.ONE;
				}
				if (drawImage) {
					Rectangle imageBounds = image.getBounds ();
					int x = 0;
					if ((style & SWT.CENTER) != 0) {
						x = Math.max (0, (clientRect.right - imageBounds.width) / 2);
					} else {
						if ((style & SWT.RIGHT) != 0) {
							x = Math.max (0, (clientRect.right - imageBounds.width));
						}
					}
					gc.drawImage (image, x, Math.max (0, (clientRect.bottom - imageBounds.height) / 2));
					result = LRESULT.ONE;
				}
				int width = ps.right - ps.left;
				int height = ps.bottom - ps.top;
				if (width != 0 && height != 0) {
					Event event = new Event ();
					event.gc = gc;
					event.x = ps.left;
					event.y = ps.top;
					event.width = width;
					event.height = height;
					sendEvent (SWT.Paint, event);
					// widget could be disposed at this point
					event.gc = null;
				}
				gc.dispose ();
			}
			return result;
		}
	}
	return super.WM_PAINT(wParam, lParam);
}

LRESULT wmDrawChild (int /*long*/ wParam, int /*long*/ lParam) {
	// AERO-GLASS TODO: this is a workaround that fixes the white backgrounds that are painted 
	// when the Alt key is pressed
	if (getBufferredPaint()) { //  && ((style & SWT.SEPARATOR) == 0)) {
		return wmBufferedPaint(handle, 0, 0);
	}
	
	DRAWITEMSTRUCT struct = new DRAWITEMSTRUCT ();
	OS.MoveMemory (struct, lParam, DRAWITEMSTRUCT.sizeof);
	drawBackground (struct.hDC);
	if ((style & SWT.SEPARATOR) != 0) {
		if ((style & SWT.SHADOW_NONE) != 0) return null;
		RECT rect = new RECT ();
		int lineWidth = OS.GetSystemMetrics (OS.SM_CXBORDER);
		int flags = (style & SWT.SHADOW_IN) != 0 ? OS.EDGE_SUNKEN : OS.EDGE_ETCHED;
		if ((style & SWT.HORIZONTAL) != 0) {
			int bottom = struct.top + Math.max (lineWidth * 2, (struct.bottom - struct.top) / 2);
			OS.SetRect (rect, struct.left, struct.top, struct.right, bottom);
			OS.DrawEdge (struct.hDC, rect, flags, OS.BF_BOTTOM);
		} else {
			int right = struct.left + Math.max (lineWidth * 2, (struct.right - struct.left) / 2);
			OS.SetRect (rect, struct.left, struct.top, right, struct.bottom);
			OS.DrawEdge (struct.hDC, rect, flags, OS.BF_RIGHT);
		}
	} else {
		int width = struct.right - struct.left;
		int height = struct.bottom - struct.top;
		if (width != 0 && height != 0) {
			boolean drawImage = image != null;
			boolean drawText = IMAGE_AND_TEXT && text.length () != 0;
			int margin = drawText && drawImage ? MARGIN : 0;
			int imageWidth = 0, imageHeight = 0;
			if (drawImage) {
				Rectangle rect = image.getBounds ();
				imageWidth = rect.width;
				imageHeight = rect.height;
			}
			RECT rect = null;
			TCHAR buffer = null;
			int textWidth = 0, textHeight = 0, flags = 0;
			if (drawText) {
				rect = new RECT ();
				flags = OS.DT_CALCRECT | OS.DT_EDITCONTROL | OS.DT_EXPANDTABS;
				if ((style & SWT.LEFT) != 0) flags |= OS.DT_LEFT;
				if ((style & SWT.CENTER) != 0) flags |= OS.DT_CENTER;
				if ((style & SWT.RIGHT) != 0) flags |= OS.DT_RIGHT;
				if ((style & SWT.WRAP) != 0) {
					flags |= OS.DT_WORDBREAK;
					rect.right = Math.max (0, width - imageWidth - margin);
				}
				buffer = new TCHAR (getCodePage (), text, true);
				OS.DrawText (struct.hDC, buffer, -1, rect, flags);
				textWidth = rect.right - rect.left;
				textHeight = rect.bottom - rect.top;
			}
			int x = 0;
			if ((style & SWT.CENTER) != 0) {
				x = Math.max (0, (width - imageWidth - textWidth - margin) / 2);
			} else {
				if ((style & SWT.RIGHT) != 0) {
					x = width - imageWidth - textWidth - margin;
				}
			}
			if (drawImage) {
				GCData data = new GCData();
				data.device = display;
				GC gc = GC.win32_new (struct.hDC, data);
				Image image = getEnabled () ? this.image : new Image (display, this.image, SWT.IMAGE_DISABLE);
				gc.drawImage (image, x, Math.max (0, (height - imageHeight) / 2));
				if (image != this.image) image.dispose ();
				gc.dispose ();
				x += imageWidth + margin;
			}
			if (drawText) {
				flags &= ~OS.DT_CALCRECT;
				rect.left = x;
				rect.right += rect.left;
				rect.top = Math.max (0, (height - textHeight) / 2);
				rect.bottom += rect.top;
				OS.DrawText (struct.hDC, buffer, -1, rect, flags);
			}
		}
	}
	return null;
}

int getThemeGlowSize() {
	int hTheme = OS.OpenThemeData(0, "CompositedWindow::Window;".toCharArray()); 
	int [] glowSize = new int[1];
	OS.GetThemeInt(hTheme, 0, 0, OS.TMT_TEXTGLOWSIZE, glowSize);
	OS.CloseThemeData(hTheme);
	
	if (glowSize[0] > 0)
		return glowSize[0];
	else
		return 12; // default value;
}

LRESULT wmBufferedPaint (int /*long*/ hWnd, int /*long*/ wParam, int /*long*/ lParam) {
	int result = 0; 
	
	// BeginPaint ...
	PAINTSTRUCT ps = new PAINTSTRUCT ();
	int hDC = OS.BeginPaint (hWnd, ps);
	
	// copy the PAINTSTRUCT coordinates into a RECT structure
	RECT rcPaintStruct = new RECT();
	rcPaintStruct.left = ps.left;
	rcPaintStruct.right = ps.right;
	rcPaintStruct.top = ps.top;
	rcPaintStruct.bottom = ps.bottom;

	// calculate the client rectangle and coordinates
	RECT rcClient = new RECT();
	OS.GetClientRect(hWnd, rcClient);
	int width = rcClient.right - rcClient.left;
	int height = rcClient.bottom - rcClient.top;

	// set up the buffered device context - the background is painted entirely black and its alpha 
	// is set to zero, resulting in a device context that is 100% transparent (if nothing is drawn to this DC,
	// the glass background will just render through)
	int [] hdcBuffered = new int[1];
	int hBufferedPaint = OS.BeginBufferedPaint(hDC, rcClient, OS.BPBF_TOPDOWNDIB, null, hdcBuffered);
	OS.PatBlt(hdcBuffered[0], 0, 0, rcClient.right - rcClient.left, rcClient.bottom - rcClient.top, OS.BLACKNESS);
	OS.BufferedPaintSetAlpha(hBufferedPaint, rcPaintStruct, (byte)0x00);

	// determine if we are drawing text and/or images
	boolean drawImage = image != null;
	boolean drawText = text != null && text.length () != 0;
	if (!IMAGE_AND_TEXT && drawImage) drawText = false;
	
	// if we are drawing image, calculate the margins and dimensions of the image that will be drawn
	int margin = drawText && drawImage ? MARGIN : 0;
	int imageWidth = 0, imageHeight = 0;
	if (drawImage) {
		Rectangle rect = image.getBounds ();
		imageWidth = rect.width;
		imageHeight = rect.height;
	}
	
	// if we are drawing text, calculate the dimensions of the text that will be drawn
	RECT rect = null;
	int textWidth = 0, textHeight = 0;
	if (drawText) {
		rect = new RECT ();
		int flags = OS.DT_CALCRECT | OS.DT_EDITCONTROL | OS.DT_EXPANDTABS;
		if ((style & SWT.LEFT) != 0) flags |= OS.DT_LEFT;
		if ((style & SWT.CENTER) != 0) flags |= OS.DT_CENTER;
		if ((style & SWT.RIGHT) != 0) flags |= OS.DT_RIGHT;
		if ((style & SWT.WRAP) != 0) {
			flags |= OS.DT_WORDBREAK;
			rect.right = Math.max (0, width - imageWidth - margin);
		}
		TCHAR buffer = new TCHAR (getCodePage (), text, true);
		OS.DrawText (hDC, buffer, -1, rect, flags);
		textWidth = rect.right - rect.left;
		textHeight = rect.bottom - rect.top;
	}
	
	// adjust the left x-coordinate based on the label's justification
	int x = 0;
	if ((style & SWT.CENTER) != 0) {
		x = Math.max (0, (width - imageWidth - textWidth - margin) / 2);
	} else {
		if ((style & SWT.RIGHT) != 0) {
			x = width - imageWidth - textWidth - margin;
		}
	}
	
	if (drawText) {
		// setup the rectangle for drawing text
		rect.left = x + imageWidth + margin;
		rect.right += rect.left;
		rect.top = Math.max (0, (height - textHeight) / 2);
		rect.bottom += rect.top;
		
		// setup the DTTOPTS structure for calling into DrawThemeTextEx - note how we call getThemeGlowSize()
		// to apply a glow around the text we are drawing to enhance readability of the text against a glass background
		DTTOPTS DttOpts = new DTTOPTS();
		DttOpts.dwFlags = DTTOPTS.DTT_COMPOSITED; // 0x2000;
		DttOpts.crText   = 0x00FFFFFF;
		DttOpts.dwFlags |= DTTOPTS.DTT_GLOWSIZE; // 0x0800;
		DttOpts.iGlowSize = getThemeGlowSize();

		// select the window's font into the buffered device context
		int hFont = OS.SendMessage(hWnd, OS.WM_GETFONT, 0, 0);
		if (hFont != 0) {
			hFont = OS.SelectObject(hdcBuffered[0], hFont);
		}
		
		// draw the text using the special DrawThemeTextEx call 
		int dwFlags = ((style & SWT.WRAP) != 0) ? OS.DT_WORDBREAK : 0;
		TCHAR textBuffer = new TCHAR (getCodePage (), text, true);
		int hTheme = OS.OpenThemeData(0, "ControlPanelStyle;".toCharArray());
		// Aero-Glass TODO: add the OS.DrawThemeTextEx() API to swt.dll
		OS.DrawThemeTextEx(hTheme, hdcBuffered[0], 0, 0, textBuffer.chars, textBuffer.length(), dwFlags, rect, DttOpts);
//		TasktopOS.DrawThemeTextEx(hTheme, hdcBuffered[0], textBuffer.chars, dwFlags, rect, DttOpts.iGlowSize); // glowSize[0]); // this is our own JNI placeholder until swt.dll gets upgraded
		OS.CloseThemeData(hTheme);

		// restore the font
		if (hFont != 0) {                        
            OS.SelectObject(hdcBuffered[0], hFont);
        }
	}

	// at this point, all drawing into the buffered device context is complete, so we can transfer its contents 
	// into the target device context by calling EndBufferedPaint
	OS.EndBufferedPaint(hBufferedPaint, true);

	// draw the image against the regular device context - PNGs work great, but there are problems with GIFs and BMPs
	if (drawImage) {
		GCData data = new GCData();
		data.device = display;
		GC gc = GC.win32_new (hDC, data);
		gc.drawImage (this.image, 0,0);
		gc.dispose ();
	}
	
	// EndPaint.
	OS.EndPaint (hDC, ps);
	
	if (result == 0) return LRESULT.ZERO;
	return new LRESULT (result);
}

}