cursor.java

源码为Eclipse开源开发平台桌面开发工具SWT的源代码,

/*******************************************************************************
 * 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.graphics;


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

/**
 * Instances of this class manage operating system resources that
 * specify the appearance of the on-screen pointer. To create a
 * cursor you specify the device and either a simple cursor style
 * describing one of the standard operating system provided cursors
 * or the image and mask data for the desired appearance.
 * <p>
 * Application code must explicitly invoke the <code>Cursor.dispose()</code> 
 * method to release the operating system resources managed by each instance
 * when those instances are no longer required.
 * </p>
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>
 *   CURSOR_ARROW, CURSOR_WAIT, CURSOR_CROSS, CURSOR_APPSTARTING, CURSOR_HELP,
 *   CURSOR_SIZEALL, CURSOR_SIZENESW, CURSOR_SIZENS, CURSOR_SIZENWSE, CURSOR_SIZEWE,
 *   CURSOR_SIZEN, CURSOR_SIZES, CURSOR_SIZEE, CURSOR_SIZEW, CURSOR_SIZENE, CURSOR_SIZESE,
 *   CURSOR_SIZESW, CURSOR_SIZENW, CURSOR_UPARROW, CURSOR_IBEAM, CURSOR_NO, CURSOR_HAND
 * </dd>
 * </dl>
 * <p>
 * Note: Only one of the above styles may be specified.
 * </p>
 */

public final class Cursor {
	
	/**
	 * the handle to the OS cursor resource
	 * (Warning: This field is platform dependent)
	 */
	public int handle;
	
	/**
	 * the device where this cursor was created
	 */
	Device device;
	
	boolean isIcon;
	
	/**
	 * data used to create a HAND cursor.
	 */
	static final byte[] HAND_SOURCE = {
		(byte)0xf9,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xf0,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xf0,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xf0,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xf0,(byte)0x3f,(byte)0xff,(byte)0xff,
		(byte)0xf0,(byte)0x07,(byte)0xff,(byte)0xff,
		(byte)0xf0,(byte)0x03,(byte)0xff,(byte)0xff,
		(byte)0xf0,(byte)0x00,(byte)0xff,(byte)0xff,

		(byte)0x10,(byte)0x00,(byte)0x7f,(byte)0xff,
		(byte)0x00,(byte)0x00,(byte)0x7f,(byte)0xff,
		(byte)0x80,(byte)0x00,(byte)0x7f,(byte)0xff,
		(byte)0xc0,(byte)0x00,(byte)0x7f,(byte)0xff,
		(byte)0xe0,(byte)0x00,(byte)0x7f,(byte)0xff,
		(byte)0xf0,(byte)0x00,(byte)0x7f,(byte)0xff,
		(byte)0xf8,(byte)0x00,(byte)0xff,(byte)0xff,
		(byte)0xfc,(byte)0x01,(byte)0xff,(byte)0xff,

		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,

		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff,
		(byte)0xff,(byte)0xff,(byte)0xff,(byte)0xff
	};
	static final byte[] HAND_MASK = {
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x06,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x06,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x06,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x06,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x06,(byte)0xc0,(byte)0x00,(byte)0x00,
		(byte)0x06,(byte)0xd8,(byte)0x00,(byte)0x00,
		(byte)0x06,(byte)0xd8,(byte)0x00,(byte)0x00,

		(byte)0x07,(byte)0xdb,(byte)0x00,(byte)0x00,
		(byte)0x67,(byte)0xfb,(byte)0x00,(byte)0x00,
		(byte)0x3f,(byte)0xff,(byte)0x00,(byte)0x00,
		(byte)0x1f,(byte)0xff,(byte)0x00,(byte)0x00,
		(byte)0x0f,(byte)0xff,(byte)0x00,(byte)0x00,
		(byte)0x07,(byte)0xff,(byte)0x00,(byte)0x00,
		(byte)0x03,(byte)0xfe,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,

		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,

		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00,
		(byte)0x00,(byte)0x00,(byte)0x00,(byte)0x00
	};

/**
 * Prevents uninitialized instances from being created outside the package.
 */
Cursor() {
}

/**	 
 * Constructs a new cursor given a device and a style
 * constant describing the desired cursor appearance.
 * <p>
 * You must dispose the cursor when it is no longer required. 
 * </p>
 *
 * @param device the device on which to allocate the cursor
 * @param style the style of cursor to allocate
 * 
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if device is null and there is no current device</li>
 *    <li>ERROR_INVALID_ARGUMENT - when an unknown style is specified</li>
 * </ul>
 * @exception SWTError <ul>
 *    <li>ERROR_NO_HANDLES - if a handle could not be obtained for cursor creation</li>
 * </ul>
 *
 * @see SWT#CURSOR_ARROW
 * @see SWT#CURSOR_WAIT
 * @see SWT#CURSOR_CROSS
 * @see SWT#CURSOR_APPSTARTING
 * @see SWT#CURSOR_HELP
 * @see SWT#CURSOR_SIZEALL
 * @see SWT#CURSOR_SIZENESW
 * @see SWT#CURSOR_SIZENS
 * @see SWT#CURSOR_SIZENWSE
 * @see SWT#CURSOR_SIZEWE
 * @see SWT#CURSOR_SIZEN
 * @see SWT#CURSOR_SIZES
 * @see SWT#CURSOR_SIZEE
 * @see SWT#CURSOR_SIZEW
 * @see SWT#CURSOR_SIZENE
 * @see SWT#CURSOR_SIZESE
 * @see SWT#CURSOR_SIZESW
 * @see SWT#CURSOR_SIZENW
 * @see SWT#CURSOR_UPARROW
 * @see SWT#CURSOR_IBEAM
 * @see SWT#CURSOR_NO
 * @see SWT#CURSOR_HAND
 */
public Cursor(Device device, int style) {
	if (device == null) device = Device.getDevice();
	if (device == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	this.device = device;
	int lpCursorName = 0;
	switch (style) {
		case SWT.CURSOR_HAND: 		lpCursorName = OS.IDC_HAND; break;
		case SWT.CURSOR_ARROW: 		lpCursorName = OS.IDC_ARROW; break;
		case SWT.CURSOR_WAIT: 		lpCursorName = OS.IDC_WAIT; break;
		case SWT.CURSOR_CROSS: 		lpCursorName = OS.IDC_CROSS; break;
		case SWT.CURSOR_APPSTARTING: 	lpCursorName = OS.IDC_APPSTARTING; break;
		case SWT.CURSOR_HELP: 		lpCursorName = OS.IDC_HELP; break;
		case SWT.CURSOR_SIZEALL: 	lpCursorName = OS.IDC_SIZEALL; break;
		case SWT.CURSOR_SIZENESW: 	lpCursorName = OS.IDC_SIZENESW; break;
		case SWT.CURSOR_SIZENS: 	lpCursorName = OS.IDC_SIZENS; break;
		case SWT.CURSOR_SIZENWSE: 	lpCursorName = OS.IDC_SIZENWSE; break;
		case SWT.CURSOR_SIZEWE: 	lpCursorName = OS.IDC_SIZEWE; break;
		case SWT.CURSOR_SIZEN: 		lpCursorName = OS.IDC_SIZENS; break;
		case SWT.CURSOR_SIZES: 		lpCursorName = OS.IDC_SIZENS; break;
		case SWT.CURSOR_SIZEE: 		lpCursorName = OS.IDC_SIZEWE; break;
		case SWT.CURSOR_SIZEW: 		lpCursorName = OS.IDC_SIZEWE; break;
		case SWT.CURSOR_SIZENE: 	lpCursorName = OS.IDC_SIZENESW; break;
		case SWT.CURSOR_SIZESE: 	lpCursorName = OS.IDC_SIZENWSE; break;
		case SWT.CURSOR_SIZESW: 	lpCursorName = OS.IDC_SIZENESW; break;
		case SWT.CURSOR_SIZENW: 	lpCursorName = OS.IDC_SIZENWSE; break;
		case SWT.CURSOR_UPARROW: 	lpCursorName = OS.IDC_UPARROW; break;
		case SWT.CURSOR_IBEAM: 		lpCursorName = OS.IDC_IBEAM; break;
		case SWT.CURSOR_NO: 		lpCursorName = OS.IDC_NO; break;
		default:
			SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	}
	handle = OS.LoadCursor(0, lpCursorName);
	/*
	* IDC_HAND is supported only on Windows 2000 and Windows 98.
	* Create a hand cursor if running in other Windows platforms.
	*/
	if (handle == 0 && style == SWT.CURSOR_HAND) {
		int width = OS.GetSystemMetrics(OS.SM_CXCURSOR);
		int height = OS.GetSystemMetrics(OS.SM_CYCURSOR);
		if (width == 32 && height == 32) {
			int hInst = OS.GetModuleHandle(null);
			if (OS.IsWinCE) SWT.error(SWT.ERROR_NOT_IMPLEMENTED);
			handle = OS.CreateCursor(hInst, 5, 0, 32, 32, HAND_SOURCE, HAND_MASK);

		}
	}
	if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	if (device.tracking) device.new_Object(this);
}

/**	 
 * Constructs a new cursor given a device, image and mask
 * data describing the desired cursor appearance, and the x
 * and y coordinates of the <em>hotspot</em> (that is, the point
 * within the area covered by the cursor which is considered
 * to be where the on-screen pointer is "pointing").