/*******************************************************************************
* Copyright (c) 2006, 2015 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.navigator;
import java.util.HashSet;
import java.util.Set;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.ListenerList;
import org.eclipse.ui.navigator.IExtensionActivationListener;
import org.eclipse.ui.navigator.INavigatorActivationService;
import org.eclipse.ui.navigator.INavigatorContentDescriptor;
import org.eclipse.ui.navigator.INavigatorContentService;
import org.eclipse.ui.navigator.INavigatorViewerDescriptor;
/**
* Stores information about programmatic bindings and activation settings.
*
*/
public class VisibilityAssistant implements IExtensionActivationListener {
private final INavigatorViewerDescriptor viewerDescriptor;
private final Set programmaticVisibilityBindings = new HashSet();
private final Set programmaticRootBindings = new HashSet();
private final ListenerList listeners = new ListenerList();
private final INavigatorActivationService activationService;
/**
* Notifies clients of changes in extension visibility or activation.
*
*/
public interface VisibilityListener {
/**
* Respond to the change in visibility or activation.
*
*/
void onVisibilityOrActivationChange();
}
/**
* Create a visibility assistant for the given viewer descriptor.
*
* @param aViewerDescriptor
* A non-nullviewer descriptor.
* @param anActivationService
* The activation service associated with the content service.
*/
public VisibilityAssistant(INavigatorViewerDescriptor aViewerDescriptor,
INavigatorActivationService anActivationService) {
Assert.isNotNull(aViewerDescriptor);
viewerDescriptor = aViewerDescriptor;
activationService = anActivationService;
activationService.addExtensionActivationListener(this);
}
/**
* Dispose of any resources held onto by this assistant.
*
*/
public void dispose() {
activationService.removeExtensionActivationListener(this);
}
/**
*
* @param theExtensions
* The extensions that should be made visible to the viewer.
* @param isRoot
*/
public void bindExtensions(String[] theExtensions, boolean isRoot) {
if (theExtensions == null) {
return;
}
for (String extension : theExtensions) {
programmaticVisibilityBindings.add(extension);
if (isRoot) {
programmaticRootBindings.add(extension);
}
}
notifyClients();
}
/**
* Add a listener to be notified when the visibility or activation state
* associated with this assistant changes.
*
* @param aListener
* a listener to be notified when the visibility or activation
* state associated with this assistant changes.
*/
public void addListener(VisibilityListener aListener) {
listeners.add(aListener);
}
/**
* Remove a listener to be notified when the visibility or activation state
* associated with this assistant changes.
*
* @param aListener
* a listener to be notified when the visibility or activation
* state associated with this assistant changes.
*/
public void removeListener(VisibilityListener aListener) {
listeners.remove(aListener);
}
private void notifyClients() {
Object[] clients = listeners.getListeners();
for (Object client : clients) {
((VisibilityListener) client).onVisibilityOrActivationChange();
}
}
/**
*
* @param aContentDescriptor
* The content descriptor of inquiry
* @return True if and only if the content descriptor is <i>active</i> and
* <i>visible</i> for the viewer descriptor and enabled for the
* given element.
*/
public boolean isVisibleAndActive(
INavigatorContentDescriptor aContentDescriptor) {
return isActive(aContentDescriptor) && isVisible(aContentDescriptor);
}
/**
*
* @param aContentDescriptor
* The content descriptor of inquiry
* @return True if and only if the given extension is <i>active</i>
*
* @see INavigatorContentService For more information on what <i>active</i>
* means.
* @see INavigatorActivationService#activateExtensions(String[], boolean)
* @see INavigatorActivationService#deactivateExtensions(String[], boolean)
*/
public boolean isActive(INavigatorContentDescriptor aContentDescriptor) {
return activationService.isNavigatorExtensionActive(aContentDescriptor
.getId());
}
/**
*
* @param aContentExtensionId
* The unique id of the content extension
* @return True if and only if the given extension is <i>active</i>
* @see INavigatorContentService For more information on what <i>active</i>
* means.
* @see INavigatorActivationService#activateExtensions(String[], boolean)
* @see INavigatorActivationService#deactivateExtensions(String[], boolean)
*/
public boolean isActive(String aContentExtensionId) {
return activationService
.isNavigatorExtensionActive(aContentExtensionId);
}
/**
*
* @param aContentDescriptor
* The content descriptor of inquiry
* @return True if and only if the given content extension is declaratively
* or programmatically made visible to the viewer.
* @see INavigatorContentService#bindExtensions(String[], boolean) For more
* information on what <i>visible</i> means.
*/
public boolean isVisible(INavigatorContentDescriptor aContentDescriptor) {
return programmaticVisibilityBindings.contains(aContentDescriptor
.getId())
|| viewerDescriptor
.isVisibleContentExtension(aContentDescriptor.getId());
}
/**
*
* @param aContentExtensionId
* The unique id of the content extension
* @return True if and only if the given content extension is declaratively
* or programmatically made visible to the viewer.
* @see INavigatorContentService#bindExtensions(String[], boolean) For more
* information on what <i>visible</i> means.
*/
public boolean isVisible(String aContentExtensionId) {
return programmaticVisibilityBindings.contains(aContentExtensionId)
|| viewerDescriptor
.isVisibleContentExtension(aContentExtensionId);
}
/**
* Return whether the given content extension is a root extension.
*
* @param aContentExtensionId
* the id of the content extension.
* @return whether the given content extension is a root extension
*/
public boolean isRootExtension(String aContentExtensionId) {
return programmaticRootBindings.contains(aContentExtensionId)
|| viewerDescriptor.isRootExtension(aContentExtensionId);
}
@Override
public void onExtensionActivation(String aViewerId,
String[] theNavigatorExtensionIds, boolean isActive) {
if (aViewerId.equals(viewerDescriptor.getViewerId())) {
notifyClients();
}
}
}