/*******************************************************************************
* Copyright (c) 2013 hangum.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the GNU Lesser Public License v2.1
* which accompanies this distribution, and is available at
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
*
* Contributors:
* hangum - initial API and implementation
******************************************************************************/
package com.hangum.tadpole.commons.viewsupport;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.ListenerList;
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.jface.viewers.StructuredViewer;
import org.eclipse.swt.events.FocusEvent;
import org.eclipse.swt.events.FocusListener;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Widget;
/*******************************************************************************
* Copyright (c) 2000, 2008 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.jdt.internal.ui.viewsupport;
/**
* A selection provider for view parts with more that one viewer.
* Tracks the focus of the viewers to provide the correct selection.
*/
public class SelectionProviderMediator implements IPostSelectionProvider {
private class InternalListener implements ISelectionChangedListener, FocusListener {
/*
* @see ISelectionChangedListener#selectionChanged
*/
public void selectionChanged(SelectionChangedEvent event) {
doSelectionChanged(event);
}
/*
* @see FocusListener#focusGained
*/
public void focusGained(FocusEvent e) {
doFocusChanged(e.widget);
}
/*
* @see FocusListener#focusLost
*/
public void focusLost(FocusEvent e) {
// do not reset due to focus behavior on GTK
// fViewerInFocus= null;
}
}
private class InternalPostSelectionListener implements
ISelectionChangedListener {
public void selectionChanged(SelectionChangedEvent event) {
doPostSelectionChanged(event);
}
}
private StructuredViewer[] fViewers;
private StructuredViewer fViewerInFocus;
private ListenerList fSelectionChangedListeners;
private ListenerList fPostSelectionChangedListeners;
/**
* @param viewers
* All viewers that can provide a selection
* @param viewerInFocus
* the viewer currently in focus or <code>null</code>
*/
public SelectionProviderMediator(StructuredViewer[] viewers, StructuredViewer viewerInFocus) {
Assert.isNotNull(viewers);
fViewers = viewers;
InternalListener listener = new InternalListener();
fSelectionChangedListeners = new ListenerList();
fPostSelectionChangedListeners = new ListenerList();
fViewerInFocus = viewerInFocus;
for (int i = 0; i < fViewers.length; i++) {
StructuredViewer viewer = fViewers[i];
viewer.addSelectionChangedListener(listener);
viewer.addPostSelectionChangedListener(new InternalPostSelectionListener());
Control control = viewer.getControl();
control.addFocusListener(listener);
}
}
private void doFocusChanged(Widget control) {
for (int i = 0; i < fViewers.length; i++) {
if (fViewers[i].getControl() == control) {
propagateFocusChanged(fViewers[i]);
return;
}
}
}
final void doPostSelectionChanged(SelectionChangedEvent event) {
ISelectionProvider provider = event.getSelectionProvider();
if (provider == fViewerInFocus) {
firePostSelectionChanged();
}
}
final void doSelectionChanged(SelectionChangedEvent event) {
ISelectionProvider provider = event.getSelectionProvider();
if (provider == fViewerInFocus) {
fireSelectionChanged();
}
}
final void propagateFocusChanged(StructuredViewer viewer) {
if (viewer != fViewerInFocus) { // OK to compare by identity
fViewerInFocus = viewer;
fireSelectionChanged();
firePostSelectionChanged();
}
}
private void fireSelectionChanged() {
if (fSelectionChangedListeners != null) {
SelectionChangedEvent event = new SelectionChangedEvent(this,
getSelection());
Object[] listeners = fSelectionChangedListeners.getListeners();
for (int i = 0; i < listeners.length; i++) {
ISelectionChangedListener listener = (ISelectionChangedListener) listeners[i];
listener.selectionChanged(event);
}
}
}
private void firePostSelectionChanged() {
if (fPostSelectionChangedListeners != null) {
SelectionChangedEvent event = new SelectionChangedEvent(this,
getSelection());
Object[] listeners = fPostSelectionChangedListeners.getListeners();
for (int i = 0; i < listeners.length; i++) {
ISelectionChangedListener listener = (ISelectionChangedListener) listeners[i];
listener.selectionChanged(event);
}
}
}
/*
* @see ISelectionProvider#addSelectionChangedListener
*/
public void addSelectionChangedListener(ISelectionChangedListener listener) {
fSelectionChangedListeners.add(listener);
}
/*
* @see ISelectionProvider#removeSelectionChangedListener
*/
public void removeSelectionChangedListener(
ISelectionChangedListener listener) {
fSelectionChangedListeners.remove(listener);
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.viewers.IPostSelectionProvider#
* addPostSelectionChangedListener
* (org.eclipse.jface.viewers.ISelectionChangedListener)
*/
public void addPostSelectionChangedListener(
ISelectionChangedListener listener) {
fPostSelectionChangedListeners.add(listener);
}
/*
* (non-Javadoc)
*
* @see org.eclipse.jface.viewers.IPostSelectionProvider#
* removePostSelectionChangedListener
* (org.eclipse.jface.viewers.ISelectionChangedListener)
*/
public void removePostSelectionChangedListener(
ISelectionChangedListener listener) {
fPostSelectionChangedListeners.remove(listener);
}
/*
* @see ISelectionProvider#getSelection
*/
public ISelection getSelection() {
if (fViewerInFocus != null) {
return fViewerInFocus.getSelection();
}
return StructuredSelection.EMPTY;
}
/*
* @see ISelectionProvider#setSelection
*/
public void setSelection(ISelection selection) {
if (fViewerInFocus != null) {
fViewerInFocus.setSelection(selection);
}
}
public void setSelection(ISelection selection, boolean reveal) {
if (fViewerInFocus != null) {
fViewerInFocus.setSelection(selection, reveal);
}
}
/**
* Returns the viewer in focus or null if no viewer has the focus
*
* @return returns the current viewer in focus
*/
public StructuredViewer getViewerInFocus() {
return fViewerInFocus;
}
}