| /******************************************************************************* |
| * Copyright (c) 2013 Christian Pontesegger and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v2.0 |
| * which accompanies this distribution, and is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * Contributors: |
| * Christian Pontesegger - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.ease.ui.dnd; |
| |
| import java.io.File; |
| import java.util.AbstractMap; |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.List; |
| |
| import org.eclipse.core.resources.IResource; |
| import org.eclipse.core.runtime.CoreException; |
| import org.eclipse.core.runtime.IConfigurationElement; |
| import org.eclipse.core.runtime.Platform; |
| import org.eclipse.ease.IScriptEngineProvider; |
| import org.eclipse.ease.Logger; |
| import org.eclipse.ease.tools.ResourceTools; |
| import org.eclipse.ease.ui.Activator; |
| import org.eclipse.jface.util.LocalSelectionTransfer; |
| import org.eclipse.jface.viewers.IStructuredSelection; |
| import org.eclipse.swt.dnd.DND; |
| import org.eclipse.swt.dnd.DropTarget; |
| import org.eclipse.swt.dnd.DropTargetAdapter; |
| import org.eclipse.swt.dnd.DropTargetEvent; |
| import org.eclipse.swt.dnd.FileTransfer; |
| import org.eclipse.swt.dnd.TextTransfer; |
| import org.eclipse.swt.dnd.Transfer; |
| import org.eclipse.swt.widgets.Control; |
| import org.eclipse.ui.part.ResourceTransfer; |
| |
| /** |
| * DND support for JavaScript shell. DND of plain text, files, resources and IDevices is supported. |
| */ |
| public final class ShellDropTarget extends DropTargetAdapter { |
| |
| private static final String EXTENSION_DROP_HANDLER_ID = "org.eclipse.ease.ui.shell"; |
| private static final String DROP_HANDLER = "dropHandler"; |
| private static final String PARAMETER_CLASS = "class"; |
| protected static final String ATTRIBUTE_PRIORITY = "priority"; |
| |
| private static Collection<IShellDropHandler> getDropTargetListeners() { |
| |
| final List<AbstractMap.SimpleEntry<Integer, IShellDropHandler>> candidates = new ArrayList<>(); |
| |
| final IConfigurationElement[] config = Platform.getExtensionRegistry().getConfigurationElementsFor(EXTENSION_DROP_HANDLER_ID); |
| for (final IConfigurationElement e : config) { |
| if (e.getName().equals(DROP_HANDLER)) { |
| // drop handler |
| // candidates.add(e); |
| try { |
| final Object executable = e.createExecutableExtension(PARAMETER_CLASS); |
| if (executable instanceof IShellDropHandler) { |
| int priority = 0; |
| try { |
| priority = Integer.parseInt(e.getAttribute(ATTRIBUTE_PRIORITY)); |
| } catch (final NumberFormatException e1) { |
| } catch (final NullPointerException e1) { |
| } |
| |
| candidates.add(new AbstractMap.SimpleEntry<>(priority, (IShellDropHandler) executable)); |
| } |
| |
| } catch (final CoreException e1) { |
| |
| Logger.error(Activator.PLUGIN_ID, "Invalid drop target listener detected in plugin \"" + e.getContributor().getName() + "\"", e1); |
| } |
| } |
| } |
| |
| // sort handler by priority |
| Collections.sort(candidates, (e1, e2) -> e2.getKey() - e1.getKey()); |
| |
| final Collection<IShellDropHandler> handler = new ArrayList<>(candidates.size()); |
| for (final AbstractMap.SimpleEntry<Integer, IShellDropHandler> candidate : candidates) |
| handler.add(candidate.getValue()); |
| |
| return handler; |
| } |
| |
| /** |
| * JavaScript shell for DND execution. |
| */ |
| private final IScriptEngineProvider fScriptEngineProvider; |
| |
| /** |
| * Add drop support for various objects. A drop will always be interpreted as <i>copy</i>, even if <i>move</i> was requested. |
| * |
| * @param parent |
| * control accepting drops |
| * @param javaScriptShell |
| * shell for DND action execution |
| */ |
| public static void addDropSupport(final Control parent, final IScriptEngineProvider engineProvider) { |
| final DropTarget target = new DropTarget(parent, DND.DROP_COPY | DND.DROP_MOVE); |
| target.setTransfer(new Transfer[] { FileTransfer.getInstance(), ResourceTransfer.getInstance(), LocalSelectionTransfer.getTransfer(), |
| TextTransfer.getInstance() }); |
| target.addDropListener(new ShellDropTarget(engineProvider)); |
| } |
| |
| /** |
| * Constructor. |
| * |
| * @param scriptShell |
| * shell for DND action execution |
| */ |
| private ShellDropTarget(final IScriptEngineProvider provider) { |
| fScriptEngineProvider = provider; |
| } |
| |
| @Override |
| public void dragEnter(final DropTargetEvent event) { |
| if ((event.detail == DND.DROP_MOVE) || (event.detail == DND.DROP_DEFAULT)) { |
| if ((event.operations & DND.DROP_COPY) != 0) |
| event.detail = DND.DROP_COPY; |
| else |
| event.detail = DND.DROP_NONE; |
| } |
| } |
| |
| @Override |
| public void drop(final DropTargetEvent event) { |
| |
| Object element = unpackElement(event.data); |
| |
| // first ask registered drop handlers |
| final Collection<IShellDropHandler> listeners = getDropTargetListeners(); |
| if (!listeners.isEmpty()) { |
| |
| for (final IShellDropHandler listener : listeners) { |
| // 1st pass: try to drop unpacked dropped element and pass it to drop handler |
| if (listener.accepts(fScriptEngineProvider.getScriptEngine(), element)) { |
| listener.performDrop(fScriptEngineProvider.getScriptEngine(), element); |
| return; |
| } |
| |
| if (!event.data.equals(element)) { |
| // 2nd pass: no listener found for unwrapped object, try with original object |
| if (listener.accepts(fScriptEngineProvider.getScriptEngine(), event.data)) { |
| listener.performDrop(fScriptEngineProvider.getScriptEngine(), event.data); |
| return; |
| } |
| } |
| } |
| } |
| |
| // no drop processor found, try generic approaches |
| |
| // resolve nice filename for workspace resources |
| if (element instanceof IResource) |
| element = ResourceTools.toAbsoluteLocation(element, null); |
| |
| fScriptEngineProvider.getScriptEngine().executeAsync(element.toString()); |
| } |
| |
| private Object unpackElement(Object element) { |
| // look for file system files |
| if (element instanceof String[]) { |
| // drop of external files (eg. from explorer) |
| final File[] files = new File[((String[]) element).length]; |
| for (int i = 0; i < files.length; i++) |
| files[i] = new File(((String[]) element)[i]); |
| |
| element = files; |
| } |
| |
| // unpack selections |
| if (element instanceof IStructuredSelection) |
| element = ((IStructuredSelection) element).toArray(); |
| |
| // unpack arrays with a single element |
| if ((element instanceof Object[]) && (((Object[]) element).length == 1)) |
| element = ((Object[]) element)[0]; |
| |
| // unpack collections with a single element |
| if ((element instanceof Collection<?>) && (((Collection<?>) element).size() == 1)) |
| element = ((Collection<?>) element).iterator().next(); |
| |
| return element; |
| } |
| } |