path: root/org.eclipse.jface.text/src/org/eclipse/jface/text/IWidgetTokenKeeperExtension.java

/*******************************************************************************
 * Copyright (c) 2000, 2004 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jface.text;

/**
 * Extension interface to <code>IWidgetTokenKeeper</code>. Replaces the original
 * <code>requestWidgetToken</code> functionality with a new priority based approach.
 * Adds the concept of focus handling.
 * 
 * @since 3.0
 */
public interface IWidgetTokenKeeperExtension {
	
	/**
	 * The given widget token owner requests the widget token  from 
	 * this token keeper. Returns  <code>true</code> if the token is released
	 * by this token keeper. Note, the keeper must not call 
	 * <code>releaseWidgetToken(IWidgetTokenKeeper)</code> explicitly.
	 * 
	 * <p>The general contract is that the receiver should release the token
	 * if <code>priority</code> exceeds the receiver's priority.</p>
	 * 
	 * @param owner the token owner
	 * @param priority the priority of the request
	 * @return <code>true</code> if token has been released <code>false</code> otherwise
	 */
	boolean requestWidgetToken(IWidgetTokenOwner owner, int priority);
	
	/**
	 * Requests the receiver to give focus to its popup shell, hover, or similar. There is
	 * no assumption made whether the receiver actually succeeded in taking the focus. The return 
	 * value gives a hint whether the receiver tried to take focus.
	 * 
	 * @param owner the token owner
	 * @return <code>true</code> if the receiver tried to take focus, <code>false</code> if it did not.
	 */
	boolean setFocus(IWidgetTokenOwner owner);
}