/******************************************************************************* * Copyright (c) 2000, 2004 IBM Corporation and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Common Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/cpl-v10.html *  * Contributors: *     IBM Corporation - initial API and implementation *******************************************************************************/package org.eclipse.swt.widgets;import org.eclipse.swt.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. * <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 intended to be subclassed <em>only</em> * within the SWT implementation. * </p> */public class Label extends Control {	String text = "";	Image image;	int font;	static final int 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 callWindowProc (int msg, int wParam, int lParam) {	if (handle == 0) return 0;	return OS.CallWindowProc (LabelProc, handle, 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;	int 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);	}	/*	* NOTE: SS_BITMAP and SS_ICON are not single bit	* masks so it is necessary to test for all of the	* bits in these masks.	*/	int bits = OS.GetWindowLong (handle, OS.GWL_STYLE);	boolean isBitmap = (bits & OS.SS_BITMAP) == OS.SS_BITMAP;	boolean isIcon = (bits & OS.SS_ICON) == OS.SS_ICON;	if (isBitmap || isIcon) {		if (image != null) {			Rectangle rect = image.getBounds();			width = rect.width;			height = rect.height;		}	} else {		int hDC = OS.GetDC (handle);		int newFont = OS.SendMessage (handle, OS.WM_GETFONT, 0, 0);		int oldFont = OS.SelectObject (hDC, newFont);		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 = wHint;		}		int length = OS.GetWindowTextLength (handle);		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 = rect.bottom - rect.top;		if (height == 0) {			TEXTMETRIC tm = OS.IsUnicode ? (TEXTMETRIC) new TEXTMETRICW () : new TEXTMETRICA ();			OS.GetTextMetrics (hDC, tm);			height = tm.tmHeight;		}		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 size.	*/	if (OS.IsWinCE) {		if (!isBitmap && !isIcon) width += 2;	}	return new Point (width, height);}/** * 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;}/** * 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;}/** Not currently used.*/boolean getWrap () {	int bits = OS.GetWindowLong (handle, OS.GWL_STYLE);	if ((bits & (OS.SS_RIGHT | OS.SS_CENTER)) != 0) return true;	if ((bits & OS.SS_LEFTNOWORDWRAP) != 0) return false;	return true;}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);	/*	* Feature in Windows.  The windows label does not align