| /******************************************************************************* |
| * Copyright (c) 2005 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.contexts; |
| |
| import org.eclipse.core.expressions.IEvaluationContext; |
| import org.eclipse.ui.internal.services.IEvaluationResultCache; |
| |
| /** |
| * <p> |
| * A token representing the activation of a context. This token can later be |
| * used to cancel that activation. Without this token, then context will only |
| * become inactive if the component in which the context was activated is |
| * destroyed. |
| * </p> |
| * <p> |
| * This interface is not intended to be implemented or extended by clients. |
| * </p> |
| * |
| * @since 3.1 |
| * @see org.eclipse.ui.ISources |
| * @see org.eclipse.ui.ISourceProvider |
| */ |
| public interface IContextActivation extends IEvaluationResultCache { |
| |
| /** |
| * Clears the cached computation of the <code>isActive</code> method, if |
| * any. This method is only intended for internal use. It provides a |
| * mechanism by which <code>ISourceProvider</code> events can invalidate |
| * state on a <code>IContextActivation</code> instance. |
| * |
| * @deprecated Use {@link IEvaluationResultCache#clearResult()} instead. |
| */ |
| public void clearActive(); |
| |
| /** |
| * Returns the identifier of the context that is being activated. |
| * |
| * @return The context identifier; never <code>null</code>. |
| */ |
| public String getContextId(); |
| |
| /** |
| * Returns the context service from which this activation was requested. |
| * This is used to ensure that an activation can only be retracted from the |
| * same service which issued it. |
| * |
| * @return The context service; never <code>null</code>. |
| */ |
| public IContextService getContextService(); |
| |
| /** |
| * Returns whether this context activation is currently active -- given the |
| * current state of the workbench. This method should cache its computation. |
| * The cache will be cleared by a call to <code>clearActive</code>. |
| * |
| * @param context |
| * The context in which this state should be evaluated; must not |
| * be <code>null</code>. |
| * @return <code>true</code> if the activation is currently active; |
| * <code>false</code> otherwise. |
| * @deprecated Use |
| * {@link IEvaluationResultCache#evaluate(IEvaluationContext)} |
| * instead. |
| */ |
| public boolean isActive(IEvaluationContext context); |
| } |