+++ /dev/null
-/*******************************************************************************
- * Copyright (c) 2000, 2003 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 net.sourceforge.phpdt.internal.ui.dnd;
-
-import org.eclipse.jface.util.Assert;
-import org.eclipse.jface.viewers.StructuredViewer;
-import org.eclipse.swt.dnd.DND;
-import org.eclipse.swt.dnd.DropTargetEvent;
-import org.eclipse.swt.dnd.DropTargetListener;
-import org.eclipse.swt.graphics.Point;
-import org.eclipse.swt.graphics.Rectangle;
-import org.eclipse.swt.widgets.Item;
-import org.eclipse.swt.widgets.TableItem;
-import org.eclipse.swt.widgets.TreeItem;
-
-/**
- * A drag and drop adapter to be used together with structured viewers. The
- * adapater delegates the <code>dragEnter</code>, <code>dragOperationChanged
- * </code>,
- * <code>dragOver</code> and <code>dropAccept</code> method to the
- * <code>validateDrop</code> method. Furthermore it adds location feedback.
- */
-public class JdtViewerDropAdapter implements DropTargetListener {
-
- /**
- * Constant describing the position of the mouse cursor relative to the
- * target object. This means the mouse is positioned slightly before the
- * target.
- */
- protected static final int LOCATION_BEFORE = 1;
-
- /**
- * Constant describing the position of the mouse cursor relative to the
- * target object. This means the mouse is positioned slightly after the
- * target.
- */
- protected static final int LOCATION_AFTER = 2;
-
- /**
- * Constant describing the position of the mouse cursor relative to the
- * target object. This means the mouse is positioned directly on the target.
- */
- protected static final int LOCATION_ON = 3;
-
- /**
- * Constant describing the position of the mouse cursor relative to the
- * target object. This means the mouse is not positioned over or near any
- * valid target.
- */
- protected static final int LOCATION_NONE = 4;
-
- /**
- * The threshold used to determine if the mouse is before or after an item.
- */
- private static final int LOCATION_EPSILON = 5;
-
- /**
- * Style to enable location feedback.
- */
- public static final int INSERTION_FEEDBACK = 1 << 1;
-
- private StructuredViewer fViewer;
-
- private int fFeedback;
-
- private boolean fShowInsertionFeedback;
-
- private int fRequestedOperation;
-
- private int fLastOperation;
-
- protected int fLocation;
-
- protected Object fTarget;
-
- public JdtViewerDropAdapter(StructuredViewer viewer, int feedback) {
- fViewer = viewer;
- Assert.isNotNull(fViewer);
- fFeedback = feedback;
- fLastOperation = -1;
- }
-
- /**
- * Controls whether the drop adapter shows insertion feedback or not.
- *
- * @param showInsertionFeedback
- * <code>true</code> if the drop adapter is supposed to show
- * insertion feedback. Otherwise <code>false</code>
- */
- public void showInsertionFeedback(boolean showInsertionFeedback) {
- fShowInsertionFeedback = showInsertionFeedback;
- }
-
- /**
- * Returns the viewer this adapter is working on.
- */
- protected StructuredViewer getViewer() {
- return fViewer;
- }
-
- // ---- Hooks to override
- // -----------------------------------------------------
-
- /**
- * The actual drop has occurred. Calls
- * <code>drop(Object target, DropTargetEvent event)
- * </code>.
- *
- * @see DropTargetListener#drop(org.eclipse.swt.dnd.DropTargetEvent)
- */
- public void drop(DropTargetEvent event) {
- drop(fTarget, event);
- }
-
- /**
- * The actual drop has occurred.
- *
- * @param target
- * the drop target in form of a domain element.
- * @param event
- * the drop traget event
- */
- public void drop(Object target, DropTargetEvent event) {
- }
-
- /**
- * Checks if the drop is valid. The method calls <code>validateDrop
- * (Object target, DropTargetEvent event). Implementors can alter the
- * <code>currentDataType</code> field and the <code>detail</code> field
- * to give feedback about drop acceptence.
- */
- public void validateDrop(DropTargetEvent event) {
- validateDrop(fTarget, event, fRequestedOperation);
- }
-
- /**
- * Checks if the drop on the current target is valid. The method can alter
- * the <code>currentDataType</code> field and the <code>
- * detail</code>
- * field to give feedback about drop acceptence.
- *
- * @param target
- * the drop target in form of a domain element.
- * @param event
- * the drop traget event
- * @param operation
- * the operation requested by the user.
- */
- public void validateDrop(Object target, DropTargetEvent event, int operation) {
- }
-
- public void dragEnter(DropTargetEvent event) {
- dragOperationChanged(event);
- }
-
- public void dragLeave(DropTargetEvent event) {
- fTarget = null;
- fLocation = LOCATION_NONE;
- }
-
- public void dragOperationChanged(DropTargetEvent event) {
- fRequestedOperation = event.detail;
- fTarget = computeTarget(event);
- fLocation = computeLocation(event);
- validateDrop(event);
- fLastOperation = event.detail;
- computeFeedback(event);
- }
-
- public void dragOver(DropTargetEvent event) {
- Object oldTarget = fTarget;
- fTarget = computeTarget(event);
-
- // set the location feedback
- int oldLocation = fLocation;
- fLocation = computeLocation(event);
- if (oldLocation != fLocation || oldTarget != fTarget
- || fLastOperation != event.detail) {
- validateDrop(event);
- fLastOperation = event.detail;
- } else {
- event.detail = fLastOperation;
- }
- computeFeedback(event);
- }
-
- public void dropAccept(DropTargetEvent event) {
- fTarget = computeTarget(event);
- validateDrop(event);
- fLastOperation = event.detail;
- }
-
- /**
- * Returns the data held by <code>event.item</code>. Inside a viewer this
- * corresponds to the items data model element.
- */
- protected Object computeTarget(DropTargetEvent event) {
- return event.item == null ? null : event.item.getData();
- }
-
- /**
- * Returns the position of the given coordinates relative to the given
- * target. The position is determined to be before, after, or on the item,
- * based on some threshold value. The return value is one of the LOCATION_*
- * constants defined in this class.
- */
- final protected int computeLocation(DropTargetEvent event) {
- if (!(event.item instanceof Item))
- return LOCATION_NONE;
-
- Item item = (Item) event.item;
- Point coordinates = fViewer.getControl().toControl(
- new Point(event.x, event.y));
- Rectangle bounds = getBounds(item);
- if (bounds == null) {
- return LOCATION_NONE;
- }
- if ((coordinates.y - bounds.y) < LOCATION_EPSILON) {
- return LOCATION_BEFORE;
- }
- if ((bounds.y + bounds.height - coordinates.y) < LOCATION_EPSILON) {
- return LOCATION_AFTER;
- }
- return LOCATION_ON;
- }
-
- /**
- * Returns the bounds of the given item, or <code>null</code> if it is not
- * a valid type of item.
- */
- private Rectangle getBounds(Item item) {
- if (item instanceof TreeItem)
- return ((TreeItem) item).getBounds();
-
- if (item instanceof TableItem)
- return ((TableItem) item).getBounds(0);
-
- return null;
- }
-
- /**
- * Sets the drag under feedback corresponding to the value of
- * <code>fLocation</code> and the <code>INSERTION_FEEDBACK</code> style
- * bit.
- */
- protected void computeFeedback(DropTargetEvent event) {
- if (!fShowInsertionFeedback && fLocation != LOCATION_NONE) {
- event.feedback = DND.FEEDBACK_SELECT;
- } else {
- if (fLocation == LOCATION_BEFORE) {
- event.feedback = DND.FEEDBACK_INSERT_BEFORE;
- } else if (fLocation == LOCATION_AFTER) {
- event.feedback = DND.FEEDBACK_INSERT_AFTER;
- }
- }
- event.feedback |= fFeedback;
- }
-
- /**
- * Sets the drop operation to </code>DROP_NODE<code>.
- */
- protected void clearDropOperation(DropTargetEvent event) {
- event.detail = DND.DROP_NONE;
- }
-
- /**
- * Returns the requested drop operation.
- */
- protected int getRequestedOperation() {
- return fRequestedOperation;
- }
-}
git://secure.phpeclipse.com / phpeclipse.git / blobdiff