ActionBarContributor.java

/*******************************************************************************
 * Copyright (c) 2000, 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.gef.ui.actions;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.jface.action.IAction;
import org.eclipse.ui.IActionBars;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.actions.RetargetAction;
import org.eclipse.ui.part.EditorActionBarContributor;

/**
 * Contributes actions to the workbench.
 * !!Warning:  This class is subject to change.
 */
public abstract class ActionBarContributor 
	extends EditorActionBarContributor
{

private ActionRegistry registry = new ActionRegistry();

/**
 * Contains the {@link RetargetAction}s that are registered as global action handlers.  We
 * need to hold on to these so that we can remove them as PartListeners in dispose().
 */
private List retargetActions = new ArrayList();
private List globalActionKeys = new ArrayList();

/**
 * Adds the given action to the action registry.
 * @param action the action to add
 */
protected void addAction(IAction action) {
	getActionRegistry().registerAction(action);
}

/**
 * Indicates the existence of a global action identified by the specified key. This global
 * action is defined outside the scope of this contributor, such as the Workbench's undo
 * action, or an action provided by a workbench ActionSet. The list of global action keys
 * is used whenever the active editor is changed ({@link #setActiveEditor(IEditorPart)}).
 * Keys provided here will result in corresponding actions being obtained from the active
 * editor's <code>ActionRegistry</code>, and those actions will be registered with the
 * ActionBars for this contributor. The editor's action handler and the global action must
 * have the same key.
 * @param key the key identifying the global action
 */
protected void addGlobalActionKey(String key) {
	globalActionKeys.add(key);
}

/**
 * Adds the specified RetargetAction to this contributors <code>ActionRegistry</code>. The
 * RetargetAction is also added as a <code>IPartListener</code> of the contributor's page.
 * Also, the retarget action's ID is flagged as a global action key, by calling {@link
 * #addGlobalActionKey(String)}.
 * @param action the retarget action being added
 */
protected void addRetargetAction(RetargetAction action) {
	addAction(action);
	retargetActions.add(action);
	getPage().addPartListener(action);
	addGlobalActionKey(action.getId());
}

/**
 * Creates and initializes Actions managed by this contributor.
 */
protected abstract void buildActions();

/**
 * Subclasses must implement to declare additional global actions IDs. Only IDs which were
 * not already added directly or indirectly using {@link #addGlobalActionKey(String)} need
 * to be added.
 * @see #addGlobalActionKey(String)
 */
protected abstract void declareGlobalActionKeys();

/**
 * Disposes the contributor. Removes all {@link RetargetAction}s that were {@link
 * org.eclipse.ui.IPartListener}s on the {@link org.eclipse.ui.IWorkbenchPage} and 
 * disposes them. Also disposes the action registry.
 * <P>
 * Subclasses may extend this method to perform additional cleanup.
 * @see org.eclipse.ui.part.EditorActionBarContributor#dispose()
 */
public void dispose() {
	for (int i = 0; i < retargetActions.size(); i++) {
		RetargetAction action = (RetargetAction)retargetActions.get(i);
		getPage().removePartListener(action);
		action.dispose();
	}
	registry.dispose();
	retargetActions = null;
	registry = null;
}

/**
 * Retrieves an action from the action registry using the given ID.
 * @param id the ID of the sought action
 * @return <code>null</code> or the action if found
 */
protected IAction getAction(String id) {
	return getActionRegistry().getAction(id);
}

/**
 * returns this contributor's ActionRegsitry.
 * @return the ActionRegistry
 */
protected ActionRegistry getActionRegistry() {
	return registry;
}

/**
 * @see EditorActionBarContributor#init(IActionBars)
 */
public void init(IActionBars bars) {
	buildActions();
	declareGlobalActionKeys();
	super.init(bars);
}

/**
 * @see org.eclipse.ui.IEditorActionBarContributor#setActiveEditor(IEditorPart)
 */
public void setActiveEditor(IEditorPart editor) {
	ActionRegistry registry = (ActionRegistry)editor.getAdapter(ActionRegistry.class);
	IActionBars bars = getActionBars();
	for (int i = 0; i < globalActionKeys.size(); i++) {
		String id = (String)globalActionKeys.get(i);
		bars.setGlobalActionHandler(id, registry.getAction(id));
	}
}

}