/*******************************************************************************
* 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.dialogs;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.ui.activities.WorkbenchActivityHelper;
import org.eclipse.ui.internal.intro.IIntroConstants;
import org.eclipse.ui.views.IViewCategory;
import org.eclipse.ui.views.IViewDescriptor;
import org.eclipse.ui.views.IViewRegistry;
/**
* Provides content for viewers that wish to show Views.
*/
public class ViewContentProvider implements ITreeContentProvider {
/**
* Child cache. Map from Object->Object[]. Our hasChildren() method is
* expensive so it's better to cache the results of getChildren().
*/
private Map childMap = new HashMap();
/**
* Create a new instance of the ViewContentProvider.
*/
public ViewContentProvider() {
//no-op
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.viewers.IContentProvider#dispose()
*/
public void dispose() {
childMap.clear();
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.viewers.ITreeContentProvider#getChildren(java.lang.Object)
*/
public Object[] getChildren(Object element) {
Object[] children = (Object[]) childMap.get(element);
if (children == null) {
children = createChildren(element);
childMap.put(element, children);
}
return children;
}
/**
* Does the actual work of getChildren.
*
* @see org.eclipse.jface.viewers.ITreeContentProvider#getChildren(java.lang.Object)
*/
private Object[] createChildren(Object element) {
if (element instanceof IViewRegistry) {
IViewRegistry reg = (IViewRegistry) element;
IViewCategory [] categories = reg.getCategories();
ArrayList filtered = new ArrayList();
for (int i = 0; i < categories.length; i++) {
if (!hasChildren(categories[i])) {
continue;
}
filtered.add(categories[i]);
}
categories = (IViewCategory[]) filtered.toArray(new IViewCategory[filtered
.size()]);
// if there is only one category, return it's children directly
if (categories.length == 1) {
return getChildren(categories[0]);
}
return categories;
} else if (element instanceof IViewCategory) {
IViewDescriptor [] views = ((IViewCategory) element).getViews();
if (views != null) {
ArrayList filtered = new ArrayList();
for (int i = 0; i < views.length; i++) {
Object o = views[i];
if (WorkbenchActivityHelper.filterItem(o)) {
continue;
}
filtered.add(o);
}
return removeIntroView(filtered).toArray();
}
}
return new Object[0];
}
/**
* Removes the temporary intro view from the list so that it cannot be activated except through
* the introduction command.
*
* @param list the list of view descriptors
* @return the modified list.
* @since 3.0
*/
private ArrayList removeIntroView(ArrayList list) {
for (Iterator i = list.iterator(); i.hasNext();) {
IViewDescriptor view = (IViewDescriptor) i.next();
if (view.getId().equals(IIntroConstants.INTRO_VIEW_ID)) {
i.remove();
}
}
return list;
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.viewers.IStructuredContentProvider#getElements(java.lang.Object)
*/
public Object[] getElements(Object element) {
return getChildren(element);
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.viewers.ITreeContentProvider#getParent(java.lang.Object)
*/
public Object getParent(Object element) {
return null;
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.viewers.ITreeContentProvider#hasChildren(java.lang.Object)
*/
public boolean hasChildren(java.lang.Object element) {
if (element instanceof IViewRegistry) {
return true;
} else if (element instanceof IViewCategory) {
if (getChildren(element).length > 0) {
return true;
}
}
return false;
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.viewers.IContentProvider#inputChanged(org.eclipse.jface.viewers.Viewer,
* java.lang.Object, java.lang.Object)
*/
public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
childMap.clear();
}
}