tree.java

源码为Eclipse开源开发平台桌面开发工具SWT的源代码,

	releaseItem (item, tvItem);
	OS.SendMessage (handle, OS.TVM_DELETEITEM, 0, hItem);
	if (fixRedraw) {
		OS.SendMessage (handle, OS.WM_SETREDRAW, 1, 0);
		OS.ValidateRect (handle, null);
		/*
		* If the item that was deleted was the last child of a tree item that
		* is visible, redraw the parent item to force the +/- to be updated.
		*/
		if (OS.SendMessage (handle, OS.TVM_GETNEXTITEM, OS.TVGN_CHILD, hParent) == 0) {
			RECT rect = new RECT ();
			rect.left = hParent;
			if (OS.SendMessage (handle, OS.TVM_GETITEMRECT, 0, rect) != 0) {
				OS.InvalidateRect (handle, rect, true);
			}
		}
	}
	int count = OS.SendMessage (handle, OS.TVM_GETCOUNT, 0, 0);
	if (count == 0) {
		if (imageList != null) {
			OS.SendMessage (handle, OS.TVM_SETIMAGELIST, 0, 0);
			display.releaseImageList (imageList);
		}
		imageList = null;
		customDraw = false;
		items = new TreeItem [4];	
	}
}

int getBackgroundPixel () {
	if (OS.IsWinCE) return OS.GetSysColor (OS.COLOR_WINDOW);
	int pixel = OS.SendMessage (handle, OS.TVM_GETBKCOLOR, 0, 0);
	if (pixel == -1) return OS.GetSysColor (OS.COLOR_WINDOW);
	return pixel;
}

int getForegroundPixel () {
	if (OS.IsWinCE) return OS.GetSysColor (OS.COLOR_WINDOWTEXT);
	int pixel = OS.SendMessage (handle, OS.TVM_GETTEXTCOLOR, 0, 0);
	if (pixel == -1) return OS.GetSysColor (OS.COLOR_WINDOWTEXT);
	return pixel;
}

/**
 * Returns the item at the given point in the receiver
 * or null if no such item exists. The point is in the
 * coordinate system of the receiver.
 *
 * @param point the point used to locate the item
 * @return the item at the given point
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the point 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 TreeItem getItem (Point point) {
	checkWidget ();
	if (point == null) error (SWT.ERROR_NULL_ARGUMENT);
	TVHITTESTINFO lpht = new TVHITTESTINFO ();
	lpht.x = point.x;
	lpht.y = point.y;
	OS.SendMessage (handle, OS.TVM_HITTEST, 0, lpht);
	if (lpht.hItem != 0 && (lpht.flags & OS.TVHT_ONITEM) != 0) {
		TVITEM tvItem = new TVITEM ();
		tvItem.mask = OS.TVIF_HANDLE | OS.TVIF_PARAM;
		tvItem.hItem = lpht.hItem;
		OS.SendMessage (handle, OS.TVM_GETITEM, 0, tvItem);
		return items [tvItem.lParam];	
	}
	return null;
}

/**
 * Returns the number of items contained in the receiver
 * that are direct item children of the receiver.  The
 * number that is returned is the number of roots in the
 * tree.
 *
 * @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 ();
	int hItem = OS.SendMessage (handle, OS.TVM_GETNEXTITEM, OS.TVGN_ROOT, 0);
	if (hItem == 0) return 0;
	return getItemCount (hItem);
}

int getItemCount (int hItem) {
	int count = 0;
	while (hItem != 0) {
		hItem = OS.SendMessage (handle, OS.TVM_GETNEXTITEM, OS.TVGN_NEXT, hItem);
		count++;
	}
	return count;
}

/**
 * Returns the height of the area which would be used to
 * display <em>one</em> of the items in the tree.
 *
 * @return the height of one 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 getItemHeight () {
	checkWidget ();
	return OS.SendMessage (handle, OS.TVM_GETITEMHEIGHT, 0, 0);
}

/**
 * Returns the items contained in the receiver
 * that are direct item children of the receiver.  These
 * are the roots of the tree.
 * <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
 *
 * @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 TreeItem [] getItems () {
	checkWidget ();
	int hItem = OS.SendMessage (handle, OS.TVM_GETNEXTITEM, OS.TVGN_ROOT, 0);
	if (hItem == 0) return new TreeItem [0];
	return getItems (hItem);
}

TreeItem [] getItems (int hTreeItem) {
	int count = 0, hItem = hTreeItem;
	while (hItem != 0) {
		hItem = OS.SendMessage (handle, OS.TVM_GETNEXTITEM, OS.TVGN_NEXT, hItem);
		count++;
	}
	int index = 0;
	TreeItem [] result = new TreeItem [count];
	TVITEM tvItem = new TVITEM ();
	tvItem.mask = OS.TVIF_HANDLE | OS.TVIF_PARAM;
	tvItem.hItem = hTreeItem;
	/*
	* Feature in Windows.  In some cases an expand or collapse message
	* can occurs from within TVM_DELETEITEM.  When this happens, the item
	* being destroyed has been removed from the list of items but has not
	* been deleted from the tree.  The fix is to check for null items and
	* remove them from the list.
	*/
	while (tvItem.hItem != 0) {
		OS.SendMessage (handle, OS.TVM_GETITEM, 0, tvItem);
		TreeItem item = items [tvItem.lParam];
		if (item != null) result [index++] = item;
		tvItem.hItem = OS.SendMessage (handle, OS.TVM_GETNEXTITEM, OS.TVGN_NEXT, tvItem.hItem);
	}
	if (index != count) {
		TreeItem [] newResult = new TreeItem [index];
		System.arraycopy (result, 0, newResult, 0, index);
		result = newResult;
	}
	return result;
}

/**
 * Returns the receiver's parent item, which must be a
 * <code>TreeItem</code> or null when the receiver is a
 * root.
 *
 * @return the receiver's parent 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 TreeItem getParentItem () {
	checkWidget ();
	return null;
}

/**
 * Returns an array of <code>TreeItem</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 TreeItem [] getSelection () {
	checkWidget ();
	if ((style & SWT.SINGLE) != 0) {
		int hItem = OS.SendMessage (handle, OS.TVM_GETNEXTITEM, OS.TVGN_CARET, 0);
		if (hItem == 0) return new TreeItem [0];
		TVITEM tvItem = new TVITEM ();
		tvItem.mask = OS.TVIF_PARAM | OS.TVIF_STATE;
		tvItem.hItem = hItem;
		OS.SendMessage (handle, OS.TVM_GETITEM, 0, tvItem);
		if ((tvItem.state & OS.TVIS_SELECTED) == 0) return new TreeItem [0];
		return new TreeItem [] {items [tvItem.lParam]};
	}
	int count = 0;
	TreeItem [] guess = new TreeItem [8];
	TVITEM tvItem = new TVITEM ();
	tvItem.mask = OS.TVIF_PARAM | OS.TVIF_STATE;
	int oldProc = OS.GetWindowLong (handle, OS.GWL_WNDPROC);
	OS.SetWindowLong (handle, OS.GWL_WNDPROC, TreeProc);
	for (int i=0; i<items.length; i++) {
		TreeItem item = items [i];
		if (item != null) {
			tvItem.hItem = item.handle;
			OS.SendMessage (handle, OS.TVM_GETITEM, 0, tvItem);
			if ((tvItem.state & OS.TVIS_SELECTED) != 0) {
				if (count < guess.length) guess [count] = item;
				count++;
			}
		}
	}
	OS.SetWindowLong (handle, OS.GWL_WNDPROC, oldProc);
	if (count == 0) return new TreeItem [0];
	if (count == guess.length) return guess;
	TreeItem [] result = new TreeItem [count];
	if (count < guess.length) {
		System.arraycopy (guess, 0, result, 0, count);
		return result;
	}
	OS.SetWindowLong (handle, OS.GWL_WNDPROC, TreeProc);
	int index = 0;
	for (int i=0; i<items.length; i++) {
		TreeItem item = items [i];
		if (item != null) {
			tvItem.hItem = item.handle;
			OS.SendMessage (handle, OS.TVM_GETITEM, 0, tvItem);
			if ((tvItem.state & OS.TVIS_SELECTED) != 0) {
				result [index++] = item;
			}
		}
	}
	OS.SetWindowLong (handle, OS.GWL_WNDPROC, oldProc);
	return result;
}

/**
 * Returns the number of selected items contained in the receiver.
 *
 * @return the number of selected 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 getSelectionCount () {
	checkWidget ();
	if ((style & SWT.SINGLE) != 0) {
		int hItem = OS.SendMessage (handle, OS.TVM_GETNEXTITEM, OS.TVGN_CARET, 0);
		if (hItem == 0) return 0;
		TVITEM tvItem = new TVITEM ();
		tvItem.mask = OS.TVIF_STATE;
		tvItem.hItem = hItem;
		OS.SendMessage (handle, OS.TVM_GETITEM, 0, tvItem);
		if ((tvItem.state & OS.TVIS_SELECTED) == 0) return 0;
		return 1;
	}
	int count = 0;
	TVITEM tvItem = new TVITEM ();
	tvItem.mask = OS.TVIF_STATE;
	int oldProc = OS.GetWindowLong (handle, OS.GWL_WNDPROC);
	OS.SetWindowLong (handle, OS.GWL_WNDPROC, TreeProc);
	for (int i=0; i<items.length; i++) {
		TreeItem item = items [i];
		if (item != null) {
			tvItem.hItem = item.handle;
			OS.SendMessage (handle, OS.TVM_GETITEM, 0, tvItem);
			if ((tvItem.state & OS.TVIS_SELECTED) != 0) count++;
		}
	}
	OS.SetWindowLong (handle, OS.GWL_WNDPROC, oldProc);
	return count;
}

/**
 * Returns the item which is currently at the top of the receiver.
 * This item can change when items are expanded, collapsed, scrolled
 * or new items are added or removed.
 *
 * @return the item at the top of 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>
 * 
 * @since 2.1
 */
public TreeItem getTopItem () {
	checkWidget ();
	int hItem = OS.SendMessage (handle, OS.TVM_GETNEXTITEM, OS.TVGN_FIRSTVISIBLE, 0);
	if (hItem == 0) return null;
	TVITEM tvItem = new TVITEM ();
	tvItem.mask = OS.TVIF_PARAM;
	tvItem.hItem = hItem;
	if (OS.SendMessage (handle, OS.TVM_GETITEM, 0, tvItem) == 0) return null;
	return items [tvItem.lParam];
}

int imageIndex (Image image) {
	if (image == null) return OS.I_IMAGENONE;
	if (imageList == null) {
		int hOldList = OS.SendMessage (handle, OS.TVM_GETIMAGELIST, OS.TVSIL_NORMAL, 0);
		if (hOldList != 0) OS.ImageList_Destroy (hOldList);
		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.TVM_SETIMAGELIST, OS.TVSIL_NORMAL, hImageList);
		return index;
	}
	int index = imageList.indexOf (image);
	if (index != -1) return index;
	return imageList.add (image);
}

boolean releaseItem (TreeItem item, TVITEM tvItem) {
	int hItem = item.handle;
	if (hItem == hAnchor) hAnchor = 0;
	if (item.isDisposed ()) return false;
	tvItem.hItem = hItem;
	OS.SendMessage (handle, OS.TVM_GETITEM, 0, tvItem);
	items [tvItem.lParam] = null;
	return true;
}

void releaseItems (TreeItem [] nodes, TVITEM tvItem) {
	for (int i=0; i<nodes.length; i++) {
		TreeItem item = nodes [i];
		TreeItem [] sons = item.getItems ();
		if (sons.length != 0) {
			releaseItems (sons, tvItem);
		}
		if (releaseItem (item, tvItem)) {
			item.releaseResources ();
		}
	}
}

void releaseWidget () {
	for (int i=0; i<items.length; i++) {
		TreeItem item = items [i];
		if (item != null && !item.isDisposed ()) {
			item.releaseResources ();
		}
	}
	/*
	* Feature in Windows.  For some reason, when
	* TVM_GETIMAGELIST or TVM_SETIMAGELIST is sent,
	* the tree issues NM_CUSTOMDRAW messages.  This
	* behavior is unwanted when the tree is being
	* disposed.  The fix is to ingore NM_CUSTOMDRAW
	* messages by usnig the custom draw flag.