| /******************************************************************************* |
| * Copyright (c) 2005, 2016 IBM Corporation and others. |
| * |
| * This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License 2.0 |
| * which accompanies this distribution, and is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * SPDX-License-Identifier: EPL-2.0 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| * Lars Vogel <Lars.Vogel@gmail.com> - Bug 440810 |
| *******************************************************************************/ |
| package org.eclipse.ui.internal; |
| |
| import java.util.Collection; |
| import java.util.HashMap; |
| import java.util.HashSet; |
| import java.util.Map; |
| import org.eclipse.core.runtime.ListenerList; |
| import org.eclipse.ui.IPropertyListener; |
| import org.eclipse.ui.contexts.IContextActivation; |
| import org.eclipse.ui.contexts.IContextService; |
| import org.eclipse.ui.internal.registry.IActionSetDescriptor; |
| import org.eclipse.ui.services.IServiceLocator; |
| |
| /** |
| * Maintains a reference counted set of action sets, with a visibility mask. |
| * This is used to determine the visibility of actions in a workbench page. In a |
| * workbench page, there may be may be many conditions that can cause an action |
| * set to become visible (such as the active part, the active editor, the |
| * default visibility of the action, the properties of the perspective, etc.) |
| * The user can also explicitly mask off particular action sets in each |
| * perspective. |
| * <p> |
| * The reference count indicates how many conditions have requested that the |
| * actions be active and the mask indicates whether or not the set was disabled |
| * by the user. |
| * </p> |
| * |
| * @since 3.1 |
| */ |
| public class ActionSetManager { |
| |
| private static class ActionSetRec { |
| int showCount; |
| |
| int maskCount; |
| |
| public boolean isVisible() { |
| return maskCount == 0 && showCount > 0; |
| } |
| |
| public boolean isEmpty() { |
| return maskCount == 0 && showCount == 0; |
| } |
| } |
| |
| private HashMap actionSets = new HashMap(); |
| private HashSet visibleItems = new HashSet(); |
| |
| public static final int PROP_VISIBLE = 0; |
| public static final int PROP_HIDDEN = 1; |
| public static final int CHANGE_MASK = 0; |
| public static final int CHANGE_UNMASK = 1; |
| public static final int CHANGE_SHOW = 2; |
| public static final int CHANGE_HIDE = 3; |
| |
| private ListenerList<IPropertyListener> listeners = new ListenerList<>(); |
| private IPropertyListener contextListener; |
| private Map activationsById = new HashMap(); |
| private IContextService contextService; |
| |
| public ActionSetManager(IServiceLocator locator) { |
| contextService = locator.getService(IContextService.class); |
| addListener(getContextListener()); |
| } |
| |
| /** |
| * @return |
| */ |
| private IPropertyListener getContextListener() { |
| if (contextListener == null) { |
| contextListener = (source, propId) -> { |
| if (source instanceof IActionSetDescriptor) { |
| IActionSetDescriptor desc = (IActionSetDescriptor) source; |
| String id = desc.getId(); |
| if (propId == PROP_VISIBLE) { |
| activationsById.put(id, contextService.activateContext(id)); |
| } else if (propId == PROP_HIDDEN) { |
| IContextActivation act = (IContextActivation) activationsById.remove(id); |
| if (act != null) { |
| contextService.deactivateContext(act); |
| } |
| } |
| } |
| }; |
| } |
| return contextListener; |
| } |
| |
| public void addListener(IPropertyListener l) { |
| listeners.add(l); |
| } |
| |
| public void removeListener(IPropertyListener l) { |
| listeners.remove(l); |
| } |
| |
| private void firePropertyChange(IActionSetDescriptor descriptor, int id) { |
| for (IPropertyListener listener : listeners) { |
| listener.propertyChanged(descriptor, id); |
| } |
| } |
| |
| private ActionSetRec getRec(IActionSetDescriptor descriptor) { |
| ActionSetRec rec = (ActionSetRec) actionSets.get(descriptor); |
| |
| if (rec == null) { |
| rec = new ActionSetRec(); |
| actionSets.put(descriptor, rec); |
| } |
| |
| return rec; |
| } |
| |
| public void showAction(IActionSetDescriptor descriptor) { |
| ActionSetRec rec = getRec(descriptor); |
| |
| boolean wasVisible = rec.isVisible(); |
| rec.showCount++; |
| if (!wasVisible && rec.isVisible()) { |
| visibleItems.add(descriptor); |
| firePropertyChange(descriptor, PROP_VISIBLE); |
| if (rec.isEmpty()) { |
| actionSets.remove(descriptor); |
| } |
| } |
| } |
| |
| public void hideAction(IActionSetDescriptor descriptor) { |
| ActionSetRec rec = getRec(descriptor); |
| |
| boolean wasVisible = rec.isVisible(); |
| rec.showCount--; |
| if (wasVisible && !rec.isVisible()) { |
| visibleItems.remove(descriptor); |
| firePropertyChange(descriptor, PROP_HIDDEN); |
| if (rec.isEmpty()) { |
| actionSets.remove(descriptor); |
| } |
| } |
| } |
| |
| public void maskAction(IActionSetDescriptor descriptor) { |
| ActionSetRec rec = getRec(descriptor); |
| |
| boolean wasVisible = rec.isVisible(); |
| rec.maskCount++; |
| if (wasVisible && !rec.isVisible()) { |
| visibleItems.remove(descriptor); |
| firePropertyChange(descriptor, PROP_HIDDEN); |
| if (rec.isEmpty()) { |
| actionSets.remove(descriptor); |
| } |
| } |
| } |
| |
| public void unmaskAction(IActionSetDescriptor descriptor) { |
| ActionSetRec rec = getRec(descriptor); |
| |
| boolean wasVisible = rec.isVisible(); |
| rec.maskCount--; |
| if (!wasVisible && rec.isVisible()) { |
| visibleItems.add(descriptor); |
| firePropertyChange(descriptor, PROP_VISIBLE); |
| if (rec.isEmpty()) { |
| actionSets.remove(descriptor); |
| } |
| } |
| } |
| |
| public Collection getVisibleItems() { |
| return visibleItems; |
| } |
| |
| public void change(IActionSetDescriptor descriptor, int changeType) { |
| switch (changeType) { |
| case CHANGE_SHOW: |
| showAction(descriptor); |
| break; |
| case CHANGE_HIDE: |
| hideAction(descriptor); |
| break; |
| case CHANGE_MASK: |
| maskAction(descriptor); |
| break; |
| case CHANGE_UNMASK: |
| unmaskAction(descriptor); |
| break; |
| } |
| } |
| } |