tabfolder.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.*;
import org.eclipse.swt.events.*;

/**
 * Instances of this class implement the notebook user interface
 * metaphor.  It allows the user to select a notebook page from
 * set of pages.
 * <p>
 * The item children that may be added to instances of this class
 * must be of type <code>TabItem</code>.
 * <code>Control</code> children are created and then set into a
 * tab item using <code>TabItem#setControl</code>.
 * </p><p>
 * Note that although this class is a subclass of <code>Composite</code>,
 * it does not make sense to set a layout on it.
 * </p><p>
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>TOP, BOTTOM</dd>
 * <dt><b>Events:</b></dt>
 * <dd>Selection</dd>
 * </dl>
 * <p>
 * Note: Only one of the styles TOP and BOTTOM may be specified.
 * </p><p>
 * IMPORTANT: This class is <em>not</em> intended to be subclassed.
 * </p>
 */
public class TabFolder extends Composite {
	TabItem [] items;
	ImageList imageList;
	static final int TabFolderProc;
	static final TCHAR TabFolderClass = new TCHAR (0, OS.WC_TABCONTROL, true);
	
	/*
	* These are the undocumented control id's for the children of
	* a tab control.  Since there are no constants for these values,
	* they may change with different versions of Windows.
	*/
	static final int ID_UPDOWN = 1;
	
	static {
		WNDCLASS lpWndClass = new WNDCLASS ();
		OS.GetClassInfo (0, TabFolderClass, lpWndClass);
		TabFolderProc = lpWndClass.lpfnWndProc;
		/*
		* Feature in Windows.  The tab control window class
		* uses the CS_HREDRAW and CS_VREDRAW style bits to
		* force a full redraw of the control and all children
		* when resized.  This causes flashing.  The fix is to
		* register a new window class without these bits and
		* implement special code that damages only the exposed
		* area.
		* 
		* NOTE:  Screen readers look for the exact class name
		* of the control in order to provide the correct kind
		* of assistance.  Therefore, it is critical that the
		* new window class have the same name.  It is possible
		* to register a local window class with the same name
		* as a global class.  Since bits that affect the class
		* are being changed, it is possible that other native
		* code, other than SWT, could create a control with
		* this class name, and fail unexpectedly.
		*/
		int hInstance = OS.GetModuleHandle (null);
		int hHeap = OS.GetProcessHeap ();
		lpWndClass.hInstance = hInstance;
		lpWndClass.style &= ~(OS.CS_HREDRAW | OS.CS_VREDRAW | OS.CS_GLOBALCLASS);
		int byteCount = TabFolderClass.length () * TCHAR.sizeof;
		int lpszClassName = OS.HeapAlloc (hHeap, OS.HEAP_ZERO_MEMORY, byteCount);
		OS.MoveMemory (lpszClassName, TabFolderClass, byteCount);
		lpWndClass.lpszClassName = lpszClassName;
		OS.RegisterClass (lpWndClass);
//		OS.HeapFree (hHeap, 0, lpszClassName);	
	}

/**
 * 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
 * @see Widget#checkSubclass
 * @see Widget#getStyle
 */
public TabFolder (Composite parent, int style) {
	super (parent, checkStyle (style));
}

/**
 * Adds the listener to the collection of listeners who will
 * be notified when the receiver's selection changes, by sending
 * it one of the messages defined in the <code>SelectionListener</code>
 * interface.
 * <p>
 * When <code>widgetSelected</code> is called, the item field of the event object is valid.
 * <code>widgetDefaultSelected</code> is not called.
 * </p>
 *
 * @param listener the listener which should 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 #removeSelectionListener
 * @see SelectionEvent
 */
public void addSelectionListener(SelectionListener listener) {
	checkWidget ();
	if (listener == null) error (SWT.ERROR_NULL_ARGUMENT);
	TypedListener typedListener = new TypedListener(listener);
	addListener(SWT.Selection,typedListener);
	addListener(SWT.DefaultSelection,typedListener);
}

int callWindowProc (int msg, int wParam, int lParam) {
	if (handle == 0) return 0;
	return OS.CallWindowProc (TabFolderProc, handle, msg, wParam, lParam);
}

static int checkStyle (int style) {
	style = checkBits (style, SWT.TOP, SWT.BOTTOM, 0, 0, 0, 0);
	/*
	* Even though it is legal to create this widget
	* with scroll bars, they serve no useful purpose
	* because they do not automatically scroll the
	* widget's client area.  The fix is to clear
	* the SWT style.
	*/
	return style & ~(SWT.H_SCROLL | SWT.V_SCROLL);
}

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

public Point computeSize (int wHint, int hHint, boolean changed) {
	checkWidget ();
	RECT insetRect = new RECT (), itemRect = new RECT ();
	OS.SendMessage (handle, OS.TCM_ADJUSTRECT, 0, insetRect);
	int width = insetRect.left - insetRect.right, height = 0;
	int count = OS.SendMessage (handle, OS.TCM_GETITEMCOUNT, 0, 0);
	if (count != 0) {
		OS.SendMessage (handle, OS.TCM_GETITEMRECT, count - 1, itemRect);
		width = Math.max (width, itemRect.right - insetRect.right);
	}
	Point size = null;
	if (layout != null) {
		size = layout.computeSize (this, wHint, hHint, changed);
	} else {
		size = minimumSize (wHint, hHint, changed);
	}
	if (size.x == 0) size.x = DEFAULT_WIDTH;
	if (size.y == 0) size.y = DEFAULT_HEIGHT;
	if (wHint != SWT.DEFAULT) size.x = wHint;
	if (hHint != SWT.DEFAULT) size.y = hHint;
	width = Math.max (width, size.x);
	height = Math.max (height, size.y);
	Rectangle trim = computeTrim (0, 0, width, height);
	width = trim.width;  height = trim.height;
	return new Point (width, height);
}

public Rectangle computeTrim (int x, int y, int width, int height) {
	checkWidget ();
	RECT rect = new RECT ();
	OS.SetRect (rect, x, y, x + width, y + height);
	OS.SendMessage (handle, OS.TCM_ADJUSTRECT, 1, rect);
	int border = getBorderWidth ();
	rect.left -= border;  rect.right += border;
	rect.top -= border;  rect.bottom += border;
	int newWidth = rect.right - rect.left;
	int newHeight = rect.bottom - rect.top;
	return new Rectangle (rect.left, rect.top, newWidth, newHeight);
}

void createItem (TabItem item, int index) {
	int count = OS.SendMessage (handle, OS.TCM_GETITEMCOUNT, 0, 0);
	if (!(0 <= index && index <= count)) error (SWT.ERROR_INVALID_RANGE);
	if (count == items.length) {
		TabItem [] newItems = new TabItem [items.length + 4];
		System.arraycopy (items, 0, newItems, 0, items.length);
		items = newItems;
	}
	TCITEM tcItem = new TCITEM ();
	if (OS.SendMessage (handle, OS.TCM_INSERTITEM, index, tcItem) == -1) {
		error (SWT.ERROR_ITEM_NOT_ADDED);
	}
	System.arraycopy (items, index, items, index + 1, count - index);
	items [index] = item;
	
	/*
	* Send a selection event when the item that is added becomes
	* the new selection.  This only happens when the first item
	* is added.
	*/
	if (count == 0) {
		Event event = new Event ();
		event.item = items [0];
		sendEvent (SWT.Selection, event);
		// the widget could be destroyed at this point
	}
}

void createHandle () {
	super.createHandle ();
	state &= ~CANVAS;
	/*
	* Feature in Windows.  Despite the fact that the
	* tool tip text contains \r\n, the tooltip will
	* not honour the new line unless TTM_SETMAXTIPWIDTH
	* is set.  The fix is to set TTM_SETMAXTIPWIDTH to
	* a large value.
	*/
	int hwndToolTip = OS.SendMessage (handle, OS.TCM_GETTOOLTIPS, 0, 0);
	OS.SendMessage (hwndToolTip, OS.TTM_SETMAXTIPWIDTH, 0, 0x7FFF);
}

void createWidget () {
	super.createWidget ();
	items = new TabItem [4];
}

void destroyItem (TabItem item) {
	int count = OS.SendMessage (handle, OS.TCM_GETITEMCOUNT, 0, 0);
	int index = 0;
	while (index < count) {
		if (items [index] == item) break;
		index++;
	}
	if (index == count) return;
	int selectionIndex = OS.SendMessage (handle, OS.TCM_GETCURSEL, 0, 0);
	if (OS.SendMessage (handle, OS.TCM_DELETEITEM, index, 0) == 0) {
		error (SWT.ERROR_ITEM_NOT_REMOVED);
	}
	System.arraycopy (items, index + 1, items, index, --count - index);
	items [count] = null;
	if (count == 0) {
		if (imageList != null) {
			OS.SendMessage (handle, OS.TCM_SETIMAGELIST, 0, 0);
			display.releaseImageList (imageList);
		}
		imageList = null;
		items = new TabItem [4];
	}
	if (count > 0 && index == selectionIndex) {
		setSelection (Math.max (0, selectionIndex - 1), true);
	}
}

public Rectangle getClientArea () {
	checkWidget ();
	forceResize ();
	RECT rect = new RECT ();
	OS.GetClientRect (handle, rect);
	OS.SendMessage (handle, OS.TCM_ADJUSTRECT, 0, rect);
	int width = rect.right - rect.left;
	int height = rect.bottom - rect.top;
	return new Rectangle (rect.left, rect.top, width, height);
}

/**
 * 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 TabItem getItem (int index) {
	checkWidget ();
	int count = OS.SendMessage (handle, OS.TCM_GETITEMCOUNT, 0, 0);
	if (!(0 <= index && index < count)) error (SWT.ERROR_INVALID_RANGE);
	return items [index];
}

/**
 * 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 ();
	return OS.SendMessage (handle, OS.TCM_GETITEMCOUNT, 0, 0);
}

/**
 * Returns an array of <code>TabItem</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
 *
 * @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 TabItem [] getItems () {
	checkWidget ();
	int count = OS.SendMessage (handle, OS.TCM_GETITEMCOUNT, 0, 0);
	TabItem [] result = new TabItem [count];
	System.arraycopy (items, 0, result, 0, count);
	return result;
}

/**
 * Returns an array of <code>TabItem</code>s that are currently
 * selected in the receiver. 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 TabItem [] getSelection () {
	checkWidget ();
	int index = OS.SendMessage (handle, OS.TCM_GETCURSEL, 0, 0);
	if (index == -1) return new TabItem [0];
	return new TabItem [] {items [index]};
}

/**
 * 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
 *
 * @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 ();
	return OS.SendMessage (handle, OS.TCM_GETCURSEL, 0, 0);
}

int imageIndex (Image image) {
	if (image == null) return OS.I_IMAGENONE;
	if (imageList == null) {
		Rectangle bounds = image.getBounds ();
		imageList = display.getImageList (new Point (bounds.width, bounds.height));
		int index = imageList.indexOf (image);
		if (index == -1) index = imageList.add (image);
		int hImageList = imageList.getHandle ();
		OS.SendMessage (handle, OS.TCM_SETIMAGELIST, 0, hImageList);
		return index;
	}
	int index = imageList.indexOf (image);
	if (index != -1) return index;
	return imageList.add (image);
}

/**
 * Searches the receiver's list starting at the first item
 * (index 0) until an item is found that is equal to the 
 * argument, and returns the index of that item. If no item
 * is found, returns -1.
 *
 * @param item the search item