| /******************************************************************************* |
| * Copyright (c) 2006 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.internal.contexts; |
| |
| import java.util.Iterator; |
| |
| import org.eclipse.core.expressions.Expression; |
| import org.eclipse.ui.contexts.IContextActivation; |
| import org.eclipse.ui.contexts.IContextService; |
| import org.eclipse.ui.internal.services.INestable; |
| |
| /** |
| * <p> |
| * A context service which delegates almost all responsibility to the parent |
| * service. This service is capable of being nested inside a component that is |
| * not recognized by the "source" event mechanism. |
| * </p> |
| * <p> |
| * This class is not intended for use outside of the |
| * <code>org.eclipse.ui.workbench</code> plug-in. |
| * </p> |
| * |
| * @since 3.2 |
| */ |
| public class NestableContextService extends SlaveContextService implements |
| INestable { |
| /** |
| * Maintain the state of the context service. |
| */ |
| private boolean fActive; |
| |
| /** |
| * Construct the new nested slave context. |
| * |
| * @param parentService |
| * the parent context service; must not be <code>null</code>. |
| * @param defaultExpression |
| * A default expression to use to determine viability. It's |
| * mainly used for conflict resolution. It can be |
| * <code>null</code>. |
| */ |
| public NestableContextService(IContextService parentService, |
| Expression defaultExpression) { |
| super(parentService, defaultExpression); |
| fActive = false; |
| } |
| |
| /* |
| * (non-Javadoc) |
| * |
| * @see org.eclipse.ui.internal.contexts.SlaveContextService#doActivateContext(org.eclipse.ui.contexts.IContextActivation) |
| */ |
| protected IContextActivation doActivateContext(IContextActivation activation) { |
| if (fActive) { |
| return super.doActivateContext(activation); |
| } |
| fLocalActivations.put(activation, null); |
| return activation; |
| } |
| |
| /* |
| * (non-Javadoc) |
| * |
| * @see org.eclipse.ui.internal.services.INestable#activate() |
| */ |
| public void activate() { |
| if (fActive) { |
| return; |
| } |
| |
| Iterator c = fLocalActivations.keySet().iterator(); |
| while (c.hasNext()) { |
| IContextActivation activation = (IContextActivation) c.next(); |
| super.doActivateContext(activation); |
| } |
| fActive = true; |
| } |
| |
| /* |
| * (non-Javadoc) |
| * |
| * @see org.eclipse.ui.internal.services.INestable#deactivate() |
| */ |
| public void deactivate() { |
| if (!fActive) { |
| return; |
| } |
| deactivateContexts(fParentActivations); |
| fParentActivations.clear(); |
| |
| Iterator c = fLocalActivations.keySet().iterator(); |
| while (c.hasNext()) { |
| fLocalActivations.put(c.next(), null); |
| } |
| fActive = false; |
| } |
| } |