/*******************************************************************************
* Copyright (c) 2003, 2015 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.ui.navigator;
import java.util.ArrayList;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;
import org.eclipse.core.runtime.SafeRunner;
import org.eclipse.jface.util.LocalSelectionTransfer;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.ISelectionProvider;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.swt.dnd.DragSource;
import org.eclipse.swt.dnd.DragSourceAdapter;
import org.eclipse.swt.dnd.DragSourceEvent;
import org.eclipse.swt.dnd.Transfer;
import org.eclipse.swt.widgets.Control;
import org.eclipse.ui.internal.navigator.NavigatorSafeRunnable;
import org.eclipse.ui.internal.navigator.Policy;
import org.eclipse.ui.internal.navigator.dnd.NavigatorPluginDropAction;
import org.eclipse.ui.part.PluginTransfer;
/**
*
* Provides an implementation of {@link DragSourceAdapter} which uses the
* extensions provided by the associated {@link INavigatorContentService}.
*
* <p>
* Clients should not need to create an instance of this class unless they are
* creating their own custom viewer. Otherwise, {@link CommonViewer} configures
* its drag adapter automatically.
* </p>
*
* @see INavigatorDnDService
* @see CommonDragAdapterAssistant
* @see CommonDropAdapter
* @see CommonDropAdapterAssistant
* @see CommonViewer
* @since 3.2
*
*/
public final class CommonDragAdapter extends DragSourceAdapter {
private final INavigatorContentService contentService;
private final ISelectionProvider provider;
private CommonDragAdapterAssistant setDataAssistant;
private List<CommonDragAdapterAssistant> assistantsToUse;
/**
* Create a DragAdapter that drives the configuration of the drag data.
*
* @param aContentService
* The content service this Drag Adapter is associated with
* @param aProvider
* The provider that can give the current selection from the
* appropriate viewer.
*/
public CommonDragAdapter(INavigatorContentService aContentService,
ISelectionProvider aProvider) {
super();
contentService = aContentService;
provider = aProvider;
assistantsToUse = new ArrayList<CommonDragAdapterAssistant>();
}
/**
*
* @return An array of supported Drag Transfer types. The list contains [
* {@link LocalSelectionTransfer#getTransfer()},
* {@link PluginTransfer#getInstance()}] in addition to any
* supported types contributed by the
* {@link CommonDragAdapterAssistant assistants}.
* @see CommonDragAdapterAssistant
* @see LocalSelectionTransfer
* @see PluginTransfer
*/
public Transfer[] getSupportedDragTransfers() {
CommonDragAdapterAssistant[] assistants = contentService
.getDnDService().getCommonDragAssistants();
Set<Transfer> supportedTypes = new LinkedHashSet<Transfer>();
supportedTypes.add(PluginTransfer.getInstance());
supportedTypes.add(LocalSelectionTransfer.getTransfer());
Transfer[] transferTypes = null;
for (CommonDragAdapterAssistant assistant : assistants) {
transferTypes = assistant.getSupportedTransferTypes();
for (Transfer transferType : transferTypes) {
if (transferType != null) {
supportedTypes.add(transferType);
}
}
}
Transfer[] transfers = supportedTypes
.toArray(new Transfer[supportedTypes.size()]);
return transfers;
}
@Override
public void dragStart(final DragSourceEvent event) {
if (Policy.DEBUG_DND) {
System.out.println("CommonDragAdapter.dragStart (begin): " + event); //$NON-NLS-1$
}
SafeRunner.run(new NavigatorSafeRunnable() {
@Override
public void run() throws Exception {
DragSource dragSource = (DragSource) event.widget;
if (Policy.DEBUG_DND) {
System.out.println("CommonDragAdapter.dragStart source: " + dragSource); //$NON-NLS-1$
}
Control control = dragSource.getControl();
if (control == control.getDisplay().getFocusControl()) {
ISelection selection = provider.getSelection();
assistantsToUse.clear();
if (!selection.isEmpty()) {
LocalSelectionTransfer.getTransfer().setSelection(selection);
boolean doIt = false;
INavigatorDnDService dndService = contentService.getDnDService();
CommonDragAdapterAssistant[] assistants = dndService
.getCommonDragAssistants();
if (assistants.length == 0)
doIt = true;
for (CommonDragAdapterAssistant assistant : assistants) {
if (Policy.DEBUG_DND) {
System.out
.println("CommonDragAdapter.dragStart assistant: " + assistant); //$NON-NLS-1$
}
event.doit = true;
assistant.dragStart(event, (IStructuredSelection) selection);
doIt |= event.doit;
if (event.doit) {
if (Policy.DEBUG_DND) {
System.out
.println("CommonDragAdapter.dragStart assistant - event.doit == true"); //$NON-NLS-1$
}
assistantsToUse.add(assistant);
}
}
event.doit = doIt;
} else {
event.doit = false;
}
} else {
event.doit = false;
}
}
});
if (Policy.DEBUG_DND) {
System.out.println("CommonDragAdapter.dragStart (end): doit=" + event.doit); //$NON-NLS-1$
}
}
@Override
public void dragSetData(final DragSourceEvent event) {
final ISelection selection = LocalSelectionTransfer.getTransfer()
.getSelection();
if (Policy.DEBUG_DND) {
System.out
.println("CommonDragAdapter.dragSetData: event" + event + " selection=" + selection); //$NON-NLS-1$ //$NON-NLS-2$
}
if (LocalSelectionTransfer.getTransfer()
.isSupportedType(event.dataType)) {
event.data = selection;
if (Policy.DEBUG_DND) {
System.out
.println("CommonDragAdapter.dragSetData set LocalSelectionTransfer: " + event.data); //$NON-NLS-1$
}
} else if (PluginTransfer.getInstance().isSupportedType(event.dataType)) {
event.data = NavigatorPluginDropAction
.createTransferData(contentService);
if (Policy.DEBUG_DND) {
System.out
.println("CommonDragAdapter.dragSetData set PluginTransfer: " + event.data); //$NON-NLS-1$
}
} else if (selection instanceof IStructuredSelection) {
if (Policy.DEBUG_DND) {
System.out
.println("CommonDragAdapter.dragSetData looking for assistants"); //$NON-NLS-1$
}
for (int i = 0, len = assistantsToUse.size(); i < len; i++) {
final CommonDragAdapterAssistant assistant = assistantsToUse.get(i);
if (Policy.DEBUG_DND) {
System.out
.println("CommonDragAdapter.dragSetData assistant: " + assistant); //$NON-NLS-1$
}
Transfer[] supportedTransferTypes = assistant
.getSupportedTransferTypes();
final boolean[] getOut = new boolean[1];
for (Transfer supportedTransferType : supportedTransferTypes) {
if (supportedTransferType.isSupportedType(event.dataType)) {
SafeRunner.run(new NavigatorSafeRunnable() {
@Override
public void run() throws Exception {
if (Policy.DEBUG_DND) {
System.out
.println("CommonDragAdapter.dragSetData supported xfer type"); //$NON-NLS-1$
}
if (assistant.setDragData(event, (IStructuredSelection) selection)) {
if (Policy.DEBUG_DND) {
System.out
.println("CommonDragAdapter.dragSetData set data " + event.data); //$NON-NLS-1$
}
setDataAssistant = assistant;
getOut[0] = true;
}
}
});
if (getOut[0])
return;
}
}
}
if (Policy.DEBUG_DND) {
System.out
.println("CommonDragAdapter.dragSetData FAILED no assistant handled it"); //$NON-NLS-1$
}
event.doit = false;
} else {
if (Policy.DEBUG_DND) {
System.out
.println("CommonDragAdapter.dragSetData FAILED can't identify transfer type"); //$NON-NLS-1$
}
event.doit = false;
}
}
@Override
public void dragFinished(DragSourceEvent event) {
if (Policy.DEBUG_DND) {
System.out.println("CommonDragAdapter.dragFinished(): " + event); //$NON-NLS-1$
}
ISelection selection = LocalSelectionTransfer.getTransfer().getSelection();
if (event.doit && selection instanceof IStructuredSelection && setDataAssistant != null)
setDataAssistant.dragFinished(event, (IStructuredSelection) selection);
setDataAssistant = null;
LocalSelectionTransfer.getTransfer().setSelection(null);
// TODO Handle clean up if drop target was outside of workbench
// if (event.doit != false) {
//
// }
}
}