/*******************************************************************************
* Copyright (c) 2000, 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;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.action.IToolBarManager;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.ISelectionProvider;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.IViewPart;
import org.eclipse.ui.IWorkbenchPart;
import org.eclipse.ui.internal.registry.IWorkbenchRegistryConstants;
/**
* This class reads the registry for extensions that plug into
* 'popupMenus' extension point and deals only with the 'viewerContribution'
* elements.
*/
public class ViewerActionBuilder extends PluginActionBuilder {
private ISelectionProvider provider;
private IWorkbenchPart part;
/**
* Basic contstructor
*/
public ViewerActionBuilder() {
}
/* (non-Javadoc)
* Method declared on PluginActionBuilder.
*/
protected ActionDescriptor createActionDescriptor(
IConfigurationElement element) {
if (part instanceof IViewPart) {
return new ActionDescriptor(element, ActionDescriptor.T_VIEW, part);
}
return new ActionDescriptor(element, ActionDescriptor.T_EDITOR, part);
}
/* (non-Javadoc)
* Method declared on PluginActionBuilder.
*/
protected BasicContribution createContribution() {
return new ViewerContribution(provider);
}
/**
* Dispose of the action builder
*/
public void dispose() {
if (cache != null) {
for (int i = 0; i < cache.size(); i++) {
((BasicContribution) cache.get(i)).dispose();
}
cache = null;
}
}
/* (non-Javadoc)
* Method declared on PluginActionBuilder.
*/
protected boolean readElement(IConfigurationElement element) {
String tag = element.getName();
// Found visibility sub-element
if (currentContribution != null && tag.equals(IWorkbenchRegistryConstants.TAG_VISIBILITY)) {
((ViewerContribution) currentContribution)
.setVisibilityTest(element);
return true;
}
return super.readElement(element);
}
/**
* Reads the contributions for a viewer menu.
* This method is typically used in conjunction with <code>contribute</code> to read
* and then insert actions for a particular viewer menu.
*
* @param id the menu id
* @param prov the selection provider for the control containing the menu
* @param part the part containing the menu.
* @return <code>true</code> if 1 or more items were read.
*/
public boolean readViewerContributions(String id, ISelectionProvider prov,
IWorkbenchPart part) {
Assert.isTrue(part instanceof IViewPart || part instanceof IEditorPart);
provider = prov;
this.part = part;
readContributions(id, IWorkbenchRegistryConstants.TAG_VIEWER_CONTRIBUTION,
IWorkbenchRegistryConstants.PL_POPUP_MENU);
return (cache != null);
}
/**
* Helper class to collect the menus and actions defined within a
* contribution element.
*/
private static class ViewerContribution extends BasicContribution implements ISelectionChangedListener {
private ISelectionProvider selProvider;
private ActionExpression visibilityTest;
/**
* Create a new ViewerContribution.
*
* @param selProvider the selection provider
*/
public ViewerContribution(ISelectionProvider selProvider) {
super();
this.selProvider = selProvider;
if (selProvider != null) {
selProvider.addSelectionChangedListener(this);
}
}
/**
* Set the visibility test.
*
* @param element the element
*/
public void setVisibilityTest(IConfigurationElement element) {
visibilityTest = new ActionExpression(element);
}
/* (non-Javadoc)
* Method declared on BasicContribution.
*/
public void contribute(IMenuManager menu, boolean menuAppendIfMissing,
IToolBarManager toolbar, boolean toolAppendIfMissing) {
boolean visible = true;
if (visibilityTest != null) {
ISelection selection = selProvider.getSelection();
if (selection instanceof IStructuredSelection) {
visible = visibilityTest
.isEnabledFor((IStructuredSelection) selection);
} else {
visible = visibilityTest.isEnabledFor(selection);
}
}
if (visible) {
super.contribute(menu, menuAppendIfMissing, toolbar,
toolAppendIfMissing);
}
}
/* (non-Javadoc)
* @see org.eclipse.ui.internal.PluginActionBuilder.BasicContribution#dispose()
*/
public void dispose() {
if (selProvider != null) {
selProvider.removeSelectionChangedListener(this);
}
disposeActions();
super.dispose();
}
/**
* Rather than hooking up each action as a selection listener,
* the contribution itself is added, and propagates
* the selection changed notification to all actions.
* This simplifies cleanup, in addition to potentially reducing the number of listeners.
*
* @see ISelectionChangedListener
* @since 3.1
*/
public void selectionChanged(SelectionChangedEvent event) {
if (actions != null) {
if (actions != null) {
for (int i = 0; i < actions.size(); i++) {
PluginAction proxy = ((ActionDescriptor) actions.get(i))
.getAction();
proxy.selectionChanged(event);
}
}
}
}
}
}