1 /*******************************************************************************
2 * Copyright (c) 2007, 2017 Association for Decentralized Information Management
4 * All rights reserved. This program and the accompanying materials
5 * are made available under the terms of the Eclipse Public License v1.0
6 * which accompanies this distribution, and is available at
7 * http://www.eclipse.org/legal/epl-v10.html
10 * VTT Technical Research Centre of Finland - initial API and implementation
12 *******************************************************************************/
13 package org.simantics.diagram.ui;
15 import java.util.ArrayList;
16 import java.util.Collections;
17 import java.util.Optional;
18 import java.util.concurrent.CopyOnWriteArrayList;
19 import java.util.concurrent.TimeUnit;
21 import org.eclipse.jface.viewers.IPostSelectionProvider;
22 import org.eclipse.jface.viewers.ISelection;
23 import org.eclipse.jface.viewers.ISelectionChangedListener;
24 import org.eclipse.jface.viewers.SelectionChangedEvent;
25 import org.eclipse.jface.viewers.StructuredSelection;
26 import org.eclipse.ui.IWorkbenchPartSite;
27 import org.simantics.db.exception.DatabaseException;
28 import org.simantics.diagram.elements.AdaptableImmutableProxyElement;
29 import org.simantics.g2d.canvas.ICanvasContext;
30 import org.simantics.g2d.canvas.impl.AbstractCanvasParticipant;
31 import org.simantics.g2d.canvas.impl.DependencyReflection.Dependency;
32 import org.simantics.g2d.canvas.impl.HintReflection.HintListener;
33 import org.simantics.g2d.diagram.participant.ElementJSON;
34 import org.simantics.g2d.diagram.participant.Selection;
35 import org.simantics.g2d.element.ElementHints;
36 import org.simantics.g2d.element.IElement;
37 import org.simantics.ui.selection.WorkbenchSelectionUtils;
38 import org.simantics.utils.datastructures.hints.IHintContext.Key;
39 import org.simantics.utils.datastructures.hints.IHintObservable;
40 import org.simantics.utils.threads.IThreadWorkQueue;
41 import org.simantics.utils.threads.ThreadUtils;
42 import org.slf4j.Logger;
43 import org.slf4j.LoggerFactory;
46 * A canvas participant that listens to the #0 mouse selection and provides it
47 * forward through the {@link IPostSelectionProvider} interface.
49 * @author Tuukka Lehtonen
51 public class WorkbenchSelectionProvider extends AbstractCanvasParticipant implements IPostSelectionProvider, ElementJSON {
53 private static final Logger LOGGER = LoggerFactory.getLogger(WorkbenchSelectionProvider.class);
55 private static final long POST_SELECTION_DELAY = 300;
57 @Dependency protected Selection selection;
59 protected IThreadWorkQueue swt;
60 protected IWorkbenchPartSite site;
61 protected ISelection currentSelection = StructuredSelection.EMPTY;
62 protected CopyOnWriteArrayList<ISelectionChangedListener> listeners = new CopyOnWriteArrayList<ISelectionChangedListener>();
63 protected CopyOnWriteArrayList<ISelectionChangedListener> postListeners = new CopyOnWriteArrayList<ISelectionChangedListener>();
65 public WorkbenchSelectionProvider(IThreadWorkQueue swt) {
69 public WorkbenchSelectionProvider(IThreadWorkQueue swt, IWorkbenchPartSite site) {
73 site.setSelectionProvider(this);
77 public void addedToContext(ICanvasContext ctx) {
78 super.addedToContext(ctx);
80 if (site != null && site.getSelectionProvider() != WorkbenchSelectionProvider.this)
81 site.setSelectionProvider(WorkbenchSelectionProvider.this);
86 public void removedFromContext(ICanvasContext ctx) {
88 if (site != null && site.getSelectionProvider() == WorkbenchSelectionProvider.this)
89 site.setSelectionProvider(null);
91 super.removedFromContext(ctx);
94 public void fireSelection(Iterable<?> selection) {
95 final ISelection s = constructAdaptableSelection(selection);
98 fireSelectionChanged(s);
99 schedulePostSelectionChanged(s);
103 @HintListener(Class = Selection.class, Field = "SELECTION0")
104 public void hintChanged(IHintObservable sender, Key key, Object oldValue, Object newValue) {
105 Iterable<?> selection = (Iterable<?>) newValue;
106 fireSelection(selection);
109 @HintListener(Class = Selection.class, Field = "SELECTION0")
110 public void hintRemoved(IHintObservable sender, Key key, Object oldValue) {
111 //System.out.println("selection removed: " + oldValue);
112 fireSelection(Collections.emptyList());
115 // Post selection changed scheduling helper.
116 private int modCount = 0;
118 protected void schedulePostSelectionChanged(final ISelection s) {
119 final int count = ++modCount;
120 ThreadUtils.getNonBlockingWorkExecutor().schedule(() -> {
121 int newCount = modCount;
122 if (count != newCount)
126 swt.asyncExec(() -> {
128 firePostSelectionChanged(s);
130 }, POST_SELECTION_DELAY, TimeUnit.MILLISECONDS);
133 protected ISelection constructAdaptableSelection(Iterable<?> selection) {
134 ArrayList<Object> objects = new ArrayList<Object>();
135 for (Object o : selection) {
136 if (o instanceof IElement) {
137 IElement e = (IElement) o;
138 Object object = e.getHint(ElementHints.KEY_OBJECT);
139 if (object != null) {
140 objects.add(new AdaptableImmutableProxyElement(e));
142 System.out.println(" discarding element from selection, null object for " + e);
145 System.out.println(" unrecognized selection: " + o.getClass() + ": " + o);
148 return new StructuredSelection(objects);
151 void fireSelectionChanged(ISelection selection) {
152 SelectionChangedEvent e = new SelectionChangedEvent(this, selection);
153 for (ISelectionChangedListener l : listeners)
154 l.selectionChanged(e);
157 void firePostSelectionChanged(ISelection selection) {
158 SelectionChangedEvent e = new SelectionChangedEvent(this, selection);
159 for (ISelectionChangedListener l : postListeners)
160 l.selectionChanged(e);
164 public void addPostSelectionChangedListener(ISelectionChangedListener listener) {
165 postListeners.add(listener);
169 public void removePostSelectionChangedListener(ISelectionChangedListener listener) {
170 postListeners.remove(listener);
174 public void addSelectionChangedListener(ISelectionChangedListener listener) {
175 listeners.add(listener);
179 public void removeSelectionChangedListener(ISelectionChangedListener listener) {
180 listeners.remove(listener);
184 public ISelection getSelection() {
185 return currentSelection;
189 public void setSelection(ISelection selection) {
190 System.out.println("WorkbenchSelectionProvider: TODO: set selection: " + selection);
194 public Optional<String> getJSON(IElement element) {
195 ISelection sel = constructAdaptableSelection(Collections.singleton(element));
197 return Optional.ofNullable( WorkbenchSelectionUtils.getPossibleJSON(sel) );
198 } catch (DatabaseException e) {
199 LOGGER.error("Unexpected failure while constructing JSON from element " + element, e);
200 return Optional.empty();