decorations.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.widgets;


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

/**
 * Instances of this class provide the appearance and
 * behavior of <code>Shells</code>, but are not top
 * level shells or dialogs. Class <code>Shell</code>
 * shares a significant amount of code with this class,
 * and is a subclass.
 * <p>
 * IMPORTANT: This class was intended to be abstract and
 * should <em>never</em> be referenced or instantiated.
 * Instead, the class <code>Shell</code> should be used.
 * </p>
 * <p>
 * Instances are always displayed in one of the maximized, 
 * minimized or normal states:
 * <ul>
 * <li>
 * When an instance is marked as <em>maximized</em>, the
 * window manager will typically resize it to fill the
 * entire visible area of the display, and the instance
 * is usually put in a state where it can not be resized 
 * (even if it has style <code>RESIZE</code>) until it is
 * no longer maximized.
 * </li><li>
 * When an instance is in the <em>normal</em> state (neither
 * maximized or minimized), its appearance is controlled by
 * the style constants which were specified when it was created
 * and the restrictions of the window manager (see below).
 * </li><li>
 * When an instance has been marked as <em>minimized</em>,
 * its contents (client area) will usually not be visible,
 * and depending on the window manager, it may be
 * "iconified" (that is, replaced on the desktop by a small
 * simplified representation of itself), relocated to a
 * distinguished area of the screen, or hidden. Combinations
 * of these changes are also possible.
 * </li>
 * </ul>
 * </p>
 * Note: The styles supported by this class must be treated
 * as <em>HINT</em>s, since the window manager for the
 * desktop on which the instance is visible has ultimate
 * control over the appearance and behavior of decorations.
 * For example, some window managers only support resizable
 * windows and will always assume the RESIZE style, even if
 * it is not set.
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>BORDER, CLOSE, MIN, MAX, NO_TRIM, RESIZE, TITLE, ON_TOP, TOOL</dd>
 * <dt><b>Events:</b></dt>
 * <dd>(none)</dd>
 * </dl>
 * Class <code>SWT</code> provides two "convenience constants"
 * for the most commonly required style combinations:
 * <dl>
 * <dt><code>SHELL_TRIM</code></dt>
 * <dd>
 * the result of combining the constants which are required
 * to produce a typical application top level shell: (that 
 * is, <code>CLOSE | TITLE | MIN | MAX | RESIZE</code>)
 * </dd>
 * <dt><code>DIALOG_TRIM</code></dt>
 * <dd>
 * the result of combining the constants which are required
 * to produce a typical application dialog shell: (that 
 * is, <code>TITLE | CLOSE | BORDER</code>)
 * </dd>
 * </dl>
 * <p>
 * IMPORTANT: This class is intended to be subclassed <em>only</em>
 * within the SWT implementation.
 * </p>
 *
 * @see #getMinimized
 * @see #getMaximized
 * @see Shell
 * @see SWT
 */

public class Decorations extends Canvas {
	Image image, smallImage, largeImage;
	Image [] images;
	Menu menuBar;
	Menu [] menus;
	Control savedFocus;
	Button defaultButton, saveDefault;
	int swFlags, hAccel, nAccel;

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

/**
 * 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#BORDER
 * @see SWT#CLOSE
 * @see SWT#MIN
 * @see SWT#MAX
 * @see SWT#RESIZE
 * @see SWT#TITLE
 * @see SWT#NO_TRIM
 * @see SWT#SHELL_TRIM
 * @see SWT#DIALOG_TRIM
 * @see SWT#ON_TOP
 * @see SWT#TOOL
 * @see Widget#checkSubclass
 * @see Widget#getStyle
 */
public Decorations (Composite parent, int style) {
	super (parent, checkStyle (style));
}

void addMenu (Menu menu) {
	if (menus == null) menus = new Menu [4];
	for (int i=0; i<menus.length; i++) {
		if (menus [i] == null) {
			menus [i] = menu;
			return;
		}
	}
	Menu [] newMenus = new Menu [menus.length + 4];
	newMenus [menus.length] = menu;
	System.arraycopy (menus, 0, newMenus, 0, menus.length);
	menus = newMenus;
}

void bringToTop () {
	/*
	* This code is intentionally commented.  On some platforms,
	* the ON_TOP style creates a shell that will stay on top
	* of every other shell on the desktop.  Using SetWindowPos ()
	* with HWND_TOP caused problems on Windows 98 so this code is
	* commented out until this functionality is specified and
	* the problems are fixed.
	*/
//	if ((style & SWT.ON_TOP) != 0) {
//		int flags = OS.SWP_NOSIZE | OS.SWP_NOMOVE | OS.SWP_NOACTIVATE; 
//		OS.SetWindowPos (handle, OS.HWND_TOP, 0, 0, 0, 0, flags);
//	} else {
		OS.BringWindowToTop (handle);
//	}
}

static int checkStyle (int style) {
	if (OS.IsWinCE) {
		/*
		* Feature in WinCE PPC.  WS_MINIMIZEBOX or WS_MAXIMIZEBOX
		* are not supposed to be used.  If they are, the result
		* is a button which does not repaint correctly.  The fix
		* is to remove this style.
		*/
		if ((style & SWT.MIN) != 0) style &= ~SWT.MIN;
		if ((style & SWT.MAX) != 0) style &= ~SWT.MAX;
		return style;
	}

	/*
	* If either WS_MINIMIZEBOX or WS_MAXIMIZEBOX are set,
	* we must also set WS_SYSMENU or the buttons will not
	* appear.
	*/
	if ((style & (SWT.MIN | SWT.MAX)) != 0) style |= SWT.CLOSE;
	
	/*
	* Both WS_SYSMENU and WS_CAPTION must be set in order
	* to for the system menu to appear.
	*/
	if ((style & SWT.CLOSE) != 0) style |= SWT.TITLE;
	
	/*
	* Bug in Windows.  The WS_CAPTION style must be
	* set when the window is resizable or it does not
	* draw properly.
	*/
	/*
	* This code is intentionally commented.  It seems
	* that this problem originally in Windows 3.11,
	* has been fixed in later versions.  Because the
	* exact nature of the drawing problem is unknown,
	* keep the commented code around in case it comes
	* back.
	*/
//	if ((style & SWT.RESIZE) != 0) style |= SWT.TITLE;
	
	return style;
}

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

int callWindowProc (int msg, int wParam, int lParam) {
	return OS.DefMDIChildProc (handle, msg, wParam, lParam);
}

Control computeTabGroup () {
	return this;
}

Control computeTabRoot () {
	return this;
}

public Rectangle computeTrim (int x, int y, int width, int height) {
	checkWidget ();

	/* Get the size of the trimmings */
	RECT rect = new RECT ();
	OS.SetRect (rect, x, y, x + width, y + height);
	int bits = OS.GetWindowLong (handle, OS.GWL_STYLE);
	boolean hasMenu = OS.IsWinCE ? false : OS.GetMenu (handle) != 0;
	OS.AdjustWindowRectEx (rect, bits, hasMenu, OS.GetWindowLong (handle, OS.GWL_EXSTYLE));

	/* Get the size of the scroll bars */
	if (horizontalBar != null) rect.bottom += OS.GetSystemMetrics (OS.SM_CYHSCROLL);
	if (verticalBar != null) rect.right += OS.GetSystemMetrics (OS.SM_CXVSCROLL);

	/* Get the height of the menu bar */
	if (hasMenu) {
		RECT testRect = new RECT ();
		OS.SetRect (testRect, 0, 0, rect.right - rect.left, rect.bottom - rect.top);
		OS.SendMessage (handle, OS.WM_NCCALCSIZE, 0, testRect);
		while ((testRect.bottom - testRect.top) < height) {
			rect.top -= OS.GetSystemMetrics (OS.SM_CYMENU) - OS.GetSystemMetrics (OS.SM_CYBORDER);
			OS.SetRect(testRect, 0, 0, rect.right - rect.left, rect.bottom - rect.top);
			OS.SendMessage (handle, OS.WM_NCCALCSIZE, 0, testRect);
		}
	}
	return new Rectangle (rect.left, rect.top, rect.right - rect.left, rect.bottom - rect.top);
}

void createAccelerators () {
	hAccel = nAccel = 0;
	int maxAccel = 0;
	MenuItem [] items = display.items;
	if (menuBar == null || items == null) {
		if (!OS.IsPPC) return;
		maxAccel = 1;
	} else {
		maxAccel = OS.IsPPC ? items.length + 1 : items.length;
	}
	ACCEL accel = new ACCEL ();
	byte [] buffer1 = new byte [ACCEL.sizeof];	
	byte [] buffer2 = new byte [maxAccel * ACCEL.sizeof];
	if (menuBar != null && items != null) {
		for (int i=0; i<items.length; i++) {
			MenuItem item = items [i];
			if (item != null && item.accelerator != 0) {
				Menu menu = item.parent;
				if (menu.parent == this) {
					while (menu != null && menu != menuBar) {
						menu = menu.getParentMenu ();
					}
					if (menu == menuBar) {
						item.fillAccel (accel);
						OS.MoveMemory (buffer1, accel, ACCEL.sizeof);
						System.arraycopy (buffer1, 0, buffer2, nAccel * ACCEL.sizeof, ACCEL.sizeof);
						nAccel++;
					}
				}
			}
		}
	}
	if (OS.IsPPC) {
		/* 
		* Note on WinCE PPC.  Close the shell when user taps CTRL-Q.
		* IDOK represents the "Done Button" which also closes the shell.
		*/
		accel.fVirt = (byte) (OS.FVIRTKEY | OS.FCONTROL);
		accel.key = (short) 'Q';
		accel.cmd = (short) OS.IDOK;
		OS.MoveMemory (buffer1, accel, ACCEL.sizeof);
		System.arraycopy (buffer1, 0, buffer2, nAccel * ACCEL.sizeof, ACCEL.sizeof);
		nAccel++;			
	}
	if (nAccel != 0) hAccel = OS.CreateAcceleratorTable (buffer2, nAccel);
}

void createHandle () {
	super.createHandle ();
	if (parent == null) return;
	setParent ();
	setSystemMenu ();
}

void createWidget () {
	super.createWidget ();
	swFlags = OS.IsWinCE ? OS.SW_SHOWMAXIMIZED : OS.SW_SHOWNOACTIVATE;
	hAccel = -1;
}

void destroyAccelerators () {
	if (hAccel != 0 && hAccel != -1) OS.DestroyAcceleratorTable (hAccel);
	hAccel = -1;
}

public void dispose () {
	if (isDisposed()) return;
	if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS);
	if (!(this instanceof Shell)) {
		setVisible (false);
		if (!traverseDecorations (false)) {
			Shell shell = getShell ();
			shell.setFocus ();
		}
	}
	super.dispose ();
}

Menu findMenu (int hMenu) {
	if (menus == null) return null;
	for (int i=0; i<menus.length; i++) {
		Menu menu = menus [i];
		if (menu != null && hMenu == menu.handle) return menu;
	}
	return null;
}

void fixDecorations (Decorations newDecorations, Control control, Menu [] menus) {
	if (this == newDecorations) return;
	if (control == savedFocus) savedFocus = null;
	if (control == defaultButton) defaultButton = null;
	if (control == saveDefault) saveDefault = null;
	if (menus == null) return;
	Menu menu = control.menu;
	if (menu != null) {
		int index = 0;
		while (index <menus.length) {
			if (menus [index] == menu) {
				control.setMenu (null);
				return;
			}
			index++;
		}
		menu.fixMenus (newDecorations);
		destroyAccelerators ();
		newDecorations.destroyAccelerators ();
	}
}

public Rectangle getBounds () {
	checkWidget ();
	if (!OS.IsWinCE) {
		if (OS.IsIconic (handle)) {
			WINDOWPLACEMENT lpwndpl = new WINDOWPLACEMENT ();
			lpwndpl.length = WINDOWPLACEMENT.sizeof;
			OS.GetWindowPlacement (handle, lpwndpl);
			int width = lpwndpl.right - lpwndpl.left;
			int height = lpwndpl.bottom - lpwndpl.top;
			return new Rectangle (lpwndpl.left, lpwndpl.top, width, height);
		}
	}
	return super.getBounds ();
}