/*******************************************************************************
* Copyright (c) 2000, 2007 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.part;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.ListenerList;
import org.eclipse.core.runtime.SafeRunner;
import org.eclipse.jface.util.SafeRunnable;
import org.eclipse.jface.viewers.IPostSelectionProvider;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.ISelectionProvider;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.ui.IEditorPart;
/**
* Manages the current selection in a multi-page editor by tracking the active
* nested editor within the multi-page editor. When the selection changes,
* notifications are sent to all registered listeners.
* <p>
* This class may be instantiated; it is not intended to be subclassed.
* The base implementation of <code>MultiPageEditor.init</code> creates
* an instance of this class.
* </p>
*/
public class MultiPageSelectionProvider implements IPostSelectionProvider {
/**
* Registered selection changed listeners (element type:
* <code>ISelectionChangedListener</code>).
*/
private ListenerList listeners = new ListenerList();
/**
* Registered post selection changed listeners.
*/
private ListenerList postListeners = new ListenerList();
/**
* The multi-page editor.
*/
private MultiPageEditorPart multiPageEditor;
/**
* Creates a selection provider for the given multi-page editor.
*
* @param multiPageEditor the multi-page editor
*/
public MultiPageSelectionProvider(MultiPageEditorPart multiPageEditor) {
Assert.isNotNull(multiPageEditor);
this.multiPageEditor = multiPageEditor;
}
/* (non-Javadoc)
* Method declared on <code>ISelectionProvider</code>.
*/
public void addSelectionChangedListener(ISelectionChangedListener listener) {
listeners.add(listener);
}
/**
* Adds a listener for post selection changes in this multi page selection provider.
*
* @param listener a selection changed listener
* @since 3.2
*/
public void addPostSelectionChangedListener(ISelectionChangedListener listener) {
postListeners.add(listener);
}
/**
* Notifies all registered selection changed listeners that the editor's
* selection has changed. Only listeners registered at the time this method is
* called are notified.
*
* @param event the selection changed event
*/
public void fireSelectionChanged(final SelectionChangedEvent event) {
Object[] listeners = this.listeners.getListeners();
fireEventChange(event, listeners);
}
/**
* Notifies all post selection changed listeners that the editor's
* selection has changed.
*
* @param event the event to propogate.
* @since 3.2
*/
public void firePostSelectionChanged(final SelectionChangedEvent event) {
Object[] listeners = postListeners.getListeners();
fireEventChange(event, listeners);
}
private void fireEventChange(final SelectionChangedEvent event, Object[] listeners) {
for (int i = 0; i < listeners.length; ++i) {
final ISelectionChangedListener l = (ISelectionChangedListener) listeners[i];
SafeRunner.run(new SafeRunnable() {
public void run() {
l.selectionChanged(event);
}
});
}
}
/**
* Returns the multi-page editor.
* @return the multi-page editor.
*/
public MultiPageEditorPart getMultiPageEditor() {
return multiPageEditor;
}
/* (non-Javadoc)
* Method declared on <code>ISelectionProvider</code>.
*/
public ISelection getSelection() {
IEditorPart activeEditor = multiPageEditor.getActiveEditor();
if (activeEditor != null) {
ISelectionProvider selectionProvider = activeEditor.getSite()
.getSelectionProvider();
if (selectionProvider != null) {
return selectionProvider.getSelection();
}
}
return StructuredSelection.EMPTY;
}
/* (non-JavaDoc)
* Method declaed on <code>ISelectionProvider</code>.
*/
public void removeSelectionChangedListener(
ISelectionChangedListener listener) {
listeners.remove(listener);
}
/**
* Removes a listener for post selection changes in this multi page selection provider.
*
* @param listener a selection changed listener
* @since 3.2
*/
public void removePostSelectionChangedListener(ISelectionChangedListener listener) {
postListeners.remove(listener);
}
/* (non-Javadoc)
* Method declared on <code>ISelectionProvider</code>.
*/
public void setSelection(ISelection selection) {
IEditorPart activeEditor = multiPageEditor.getActiveEditor();
if (activeEditor != null) {
ISelectionProvider selectionProvider = activeEditor.getSite()
.getSelectionProvider();
if (selectionProvider != null) {
selectionProvider.setSelection(selection);
}
}
}
}