/*******************************************************************************
 * Copyright (c) 2008 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.core.commands;

/**
 * Extend the IHandler interface to provide some context for isEnabled()
 * requests. Clients should use {@link AbstractHandler} unless they need to
 * provide their own listener mechanism.
 * 
 * @since 3.4
 * @see AbstractHandler
 */
public interface IHandler2 extends IHandler {
	/**
	 * Called by the framework to allow the handler to update its enabled state.
	 * 
	 * @param evaluationContext
	 *            the state to evaluate against. May be <code>null</code>
	 *            which indicates that the handler can query whatever model that
	 *            is necessary. This context must not be cached.
	 */
	public void setEnabled(Object evaluationContext);
}