| /******************************************************************************* |
| * Copyright (c) 2007, 2012 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.swt.dnd; |
| |
| import org.eclipse.swt.*; |
| import org.eclipse.swt.graphics.*; |
| import org.eclipse.swt.internal.*; |
| import org.eclipse.swt.internal.win32.*; |
| import org.eclipse.swt.widgets.*; |
| |
| /** |
| * This class provides a default drag under effect (eg. select, insert, scroll and expand) |
| * when a drag occurs over a <code>Tree</code>. |
| * |
| * <p>Classes that wish to provide their own drag under effect for a <code>Tree</code> |
| * can extend the <code>TreeDropTargetEffect</code> class and override any applicable methods |
| * in <code>TreeDropTargetEffect</code> to display their own drag under effect.</p> |
| * |
| * Subclasses that override any methods of this class must call the corresponding |
| * <code>super</code> method to get the default drag under effect implementation. |
| * |
| * <p>The feedback value is either one of the FEEDBACK constants defined in |
| * class <code>DND</code> which is applicable to instances of this class, |
| * or it must be built by <em>bitwise OR</em>'ing together |
| * (that is, using the <code>int</code> "|" operator) two or more |
| * of those <code>DND</code> effect constants. |
| * </p> |
| * <p> |
| * <dl> |
| * <dt><b>Feedback:</b></dt> |
| * <dd>FEEDBACK_SELECT, FEEDBACK_INSERT_BEFORE, FEEDBACK_INSERT_AFTER, FEEDBACK_EXPAND, FEEDBACK_SCROLL</dd> |
| * </dl> |
| * </p><p> |
| * Note: Only one of the styles FEEDBACK_SELECT, FEEDBACK_INSERT_BEFORE or |
| * FEEDBACK_INSERT_AFTER may be specified. |
| * </p> |
| * |
| * @see DropTargetAdapter |
| * @see DropTargetEvent |
| * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a> |
| * |
| * @since 3.3 |
| */ |
| public class TreeDropTargetEffect extends DropTargetEffect { |
| static final int SCROLL_HYSTERESIS = 200; // milli seconds |
| static final int EXPAND_HYSTERESIS = 1000; // milli seconds |
| |
| long /*int*/ dropIndex; |
| long /*int*/ scrollIndex; |
| long scrollBeginTime; |
| long /*int*/ expandIndex; |
| long expandBeginTime; |
| TreeItem insertItem; |
| boolean insertBefore; |
| |
| /** |
| * Creates a new <code>TreeDropTargetEffect</code> to handle the drag under effect on the specified |
| * <code>Tree</code>. |
| * |
| * @param tree the <code>Tree</code> over which the user positions the cursor to drop the data |
| */ |
| public TreeDropTargetEffect(Tree tree) { |
| super(tree); |
| } |
| |
| int checkEffect(int effect) { |
| // Some effects are mutually exclusive. Make sure that only one of the mutually exclusive effects has been specified. |
| if ((effect & DND.FEEDBACK_SELECT) != 0) effect = effect & ~DND.FEEDBACK_INSERT_AFTER & ~DND.FEEDBACK_INSERT_BEFORE; |
| if ((effect & DND.FEEDBACK_INSERT_BEFORE) != 0) effect = effect & ~DND.FEEDBACK_INSERT_AFTER; |
| return effect; |
| } |
| |
| /** |
| * This implementation of <code>dragEnter</code> provides a default drag under effect |
| * for the feedback specified in <code>event.feedback</code>. |
| * |
| * For additional information see <code>DropTargetAdapter.dragEnter</code>. |
| * |
| * Subclasses that override this method should call <code>super.dragEnter(event)</code> |
| * to get the default drag under effect implementation. |
| * |
| * @param event the information associated with the drag enter event |
| * |
| * @see DropTargetAdapter |
| * @see DropTargetEvent |
| */ |
| @Override |
| public void dragEnter(DropTargetEvent event) { |
| dropIndex = -1; |
| insertItem = null; |
| expandBeginTime = 0; |
| expandIndex = -1; |
| scrollBeginTime = 0; |
| scrollIndex = -1; |
| } |
| |
| /** |
| * This implementation of <code>dragLeave</code> provides a default drag under effect |
| * for the feedback specified in <code>event.feedback</code>. |
| * |
| * For additional information see <code>DropTargetAdapter.dragLeave</code>. |
| * |
| * Subclasses that override this method should call <code>super.dragLeave(event)</code> |
| * to get the default drag under effect implementation. |
| * |
| * @param event the information associated with the drag leave event |
| * |
| * @see DropTargetAdapter |
| * @see DropTargetEvent |
| */ |
| @Override |
| public void dragLeave(DropTargetEvent event) { |
| Tree tree = (Tree) control; |
| long /*int*/ handle = tree.handle; |
| if (dropIndex != -1) { |
| TVITEM tvItem = new TVITEM (); |
| tvItem.hItem = dropIndex; |
| tvItem.mask = OS.TVIF_STATE; |
| tvItem.stateMask = OS.TVIS_DROPHILITED; |
| tvItem.state = 0; |
| OS.SendMessage (handle, OS.TVM_SETITEM, 0, tvItem); |
| dropIndex = -1; |
| } |
| if (insertItem != null) { |
| tree.setInsertMark(null, false); |
| insertItem = null; |
| } |
| expandBeginTime = 0; |
| expandIndex = -1; |
| scrollBeginTime = 0; |
| scrollIndex = -1; |
| } |
| |
| /** |
| * This implementation of <code>dragOver</code> provides a default drag under effect |
| * for the feedback specified in <code>event.feedback</code>. |
| * |
| * For additional information see <code>DropTargetAdapter.dragOver</code>. |
| * |
| * Subclasses that override this method should call <code>super.dragOver(event)</code> |
| * to get the default drag under effect implementation. |
| * |
| * @param event the information associated with the drag over event |
| * |
| * @see DropTargetAdapter |
| * @see DropTargetEvent |
| * @see DND#FEEDBACK_SELECT |
| * @see DND#FEEDBACK_INSERT_BEFORE |
| * @see DND#FEEDBACK_INSERT_AFTER |
| * @see DND#FEEDBACK_SCROLL |
| */ |
| @Override |
| public void dragOver(DropTargetEvent event) { |
| Tree tree = (Tree) getControl(); |
| int effect = checkEffect(event.feedback); |
| long /*int*/ handle = tree.handle; |
| Point coordinates = new Point(event.x, event.y); |
| coordinates = DPIUtil.autoScaleUp(tree.toControl(coordinates)); // To Pixels |
| TVHITTESTINFO lpht = new TVHITTESTINFO (); |
| lpht.x = coordinates.x; |
| lpht.y = coordinates.y; |
| OS.SendMessage (handle, OS.TVM_HITTEST, 0, lpht); |
| long /*int*/ hItem = lpht.hItem; |
| if ((effect & DND.FEEDBACK_SCROLL) == 0) { |
| scrollBeginTime = 0; |
| scrollIndex = -1; |
| } else { |
| if (hItem != -1 && scrollIndex == hItem && scrollBeginTime != 0) { |
| if (System.currentTimeMillis() >= scrollBeginTime) { |
| long /*int*/ topItem = OS.SendMessage(handle, OS.TVM_GETNEXTITEM, OS.TVGN_FIRSTVISIBLE, 0); |
| long /*int*/ nextItem = OS.SendMessage(handle, OS.TVM_GETNEXTITEM, hItem == topItem ? OS.TVGN_PREVIOUSVISIBLE : OS.TVGN_NEXTVISIBLE, hItem); |
| boolean scroll = true; |
| if (hItem == topItem) { |
| scroll = nextItem != 0; |
| } else { |
| RECT itemRect = new RECT (); |
| if (OS.TreeView_GetItemRect (handle, nextItem, itemRect, true)) { |
| RECT rect = new RECT (); |
| OS.GetClientRect (handle, rect); |
| POINT pt = new POINT (); |
| pt.x = itemRect.left; |
| pt.y = itemRect.top; |
| if (OS.PtInRect (rect, pt)) { |
| pt.y = itemRect.bottom; |
| if (OS.PtInRect (rect, pt)) scroll = false; |
| } |
| } |
| } |
| if (scroll) { |
| OS.SendMessage (handle, OS.TVM_ENSUREVISIBLE, 0, nextItem); |
| tree.redraw(); |
| } |
| scrollBeginTime = 0; |
| scrollIndex = -1; |
| } |
| } else { |
| scrollBeginTime = System.currentTimeMillis() + SCROLL_HYSTERESIS; |
| scrollIndex = hItem; |
| } |
| } |
| if ((effect & DND.FEEDBACK_EXPAND) == 0) { |
| expandBeginTime = 0; |
| expandIndex = -1; |
| } else { |
| if (hItem != -1 && expandIndex == hItem && expandBeginTime != 0) { |
| if (System.currentTimeMillis() >= expandBeginTime) { |
| if (OS.SendMessage (handle, OS.TVM_GETNEXTITEM, OS.TVGN_CHILD, hItem) != 0) { |
| TreeItem item = (TreeItem)tree.getDisplay().findWidget(tree.handle, hItem); |
| if (item != null && !item.getExpanded()) { |
| item.setExpanded(true); |
| tree.redraw(); |
| Event expandEvent = new Event (); |
| expandEvent.item = item; |
| tree.notifyListeners(SWT.Expand, expandEvent); |
| } |
| } |
| expandBeginTime = 0; |
| expandIndex = -1; |
| } |
| } else { |
| expandBeginTime = System.currentTimeMillis() + EXPAND_HYSTERESIS; |
| expandIndex = hItem; |
| } |
| } |
| if (dropIndex != -1 && (dropIndex != hItem || (effect & DND.FEEDBACK_SELECT) == 0)) { |
| TVITEM tvItem = new TVITEM (); |
| tvItem.hItem = dropIndex; |
| tvItem.mask = OS.TVIF_STATE; |
| tvItem.stateMask = OS.TVIS_DROPHILITED; |
| tvItem.state = 0; |
| OS.SendMessage (handle, OS.TVM_SETITEM, 0, tvItem); |
| dropIndex = -1; |
| } |
| if (hItem != -1 && hItem != dropIndex && (effect & DND.FEEDBACK_SELECT) != 0) { |
| TVITEM tvItem = new TVITEM (); |
| tvItem.hItem = hItem; |
| tvItem.mask = OS.TVIF_STATE; |
| tvItem.stateMask = OS.TVIS_DROPHILITED; |
| tvItem.state = OS.TVIS_DROPHILITED; |
| OS.SendMessage (handle, OS.TVM_SETITEM, 0, tvItem); |
| dropIndex = hItem; |
| } |
| if ((effect & DND.FEEDBACK_INSERT_BEFORE) != 0 || (effect & DND.FEEDBACK_INSERT_AFTER) != 0) { |
| boolean before = (effect & DND.FEEDBACK_INSERT_BEFORE) != 0; |
| /* |
| * Bug in Windows. When TVM_SETINSERTMARK is used to set |
| * an insert mark for a tree and an item is expanded or |
| * collapsed near the insert mark, the tree does not redraw |
| * the insert mark properly. The fix is to hide and show |
| * the insert mark whenever an item is expanded or collapsed. |
| * Since the insert mark can not be queried from the tree, |
| * use the Tree API rather than calling the OS directly. |
| */ |
| TreeItem item = (TreeItem)tree.getDisplay().findWidget(tree.handle, hItem); |
| if (item != null) { |
| if (item != insertItem || before != insertBefore) { |
| tree.setInsertMark(item, before); |
| } |
| insertItem = item; |
| insertBefore = before; |
| } else { |
| if (insertItem != null) { |
| tree.setInsertMark(null, false); |
| } |
| insertItem = null; |
| } |
| } else { |
| if (insertItem != null) { |
| tree.setInsertMark(null, false); |
| } |
| insertItem = null; |
| } |
| } |
| } |