/*******************************************************************************
* Mission Control Technologies, Copyright (c) 2009-2012, United States Government
* as represented by the Administrator of the National Aeronautics and Space
* Administration. All rights reserved.
*
* The MCT platform is licensed under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0.
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*
* MCT includes source code licensed under additional open source licenses. See
* the MCT Open Source Licenses file included with this distribution or the About
* MCT Licenses dialog available at runtime from the MCT Help menu for additional
* information.
*******************************************************************************/
package gov.nasa.arc.mct.gui.housing;
import gov.nasa.arc.mct.gui.View;
import gov.nasa.arc.mct.gui.SelectionProvider;
import gov.nasa.arc.mct.util.logging.MCTLogger;
import java.awt.Component;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
/**
* This class manages selection based on a set of disjoint containers, each having their own notion of
* selection. The selection manager returns the last active set of selected manifestations based on the set of managed <code>SelectionProvider</code>
* instances. This is determined based on the events fired.
* This class is not thread safe and is expected to be used from the AWT Event Thread.
* @author chris.webster@nasa.gov
*/
public class SelectionManager implements SelectionProvider, PropertyChangeListener {
private final PropertyChangeSupport pcs;
private final List<SelectionProvider> containers;
private Collection<View> activeSelection = Collections.emptyList();
private static final MCTLogger LOGGER = MCTLogger.getLogger(SelectionManager.class);
/**
* Creates a new SelectionManager instance.
* @param eventSource to use for <code>PropertyChangeEvent</code>'s
*/
public SelectionManager(Object eventSource) {
pcs = new PropertyChangeSupport(eventSource);
containers = new ArrayList<SelectionProvider>();
}
/**
* Add component to the list of managed components
* @param c component to listen for focus changes on, the components should also implement <code>SelectionProvider</code>
*/
public void manageComponent(Component c) {
if (!(c instanceof SelectionProvider)) {
LOGGER.warn("class " + c + "not instance of SelectionProvider. Focus will be ignored");
} else {
SelectionProvider provider = (SelectionProvider) c;
containers.add(provider);
provider.addSelectionChangeListener(this);
}
}
@Override
public void addSelectionChangeListener(PropertyChangeListener listener) {
pcs.addPropertyChangeListener(SelectionProvider.SELECTION_CHANGED_PROP, listener);
}
@Override
public Collection<View> getSelectedManifestations() {
return activeSelection;
}
@Override
public void removeSelectionChangeListener(PropertyChangeListener listener) {
pcs.removePropertyChangeListener(SelectionProvider.SELECTION_CHANGED_PROP, listener);
}
@Override
public void clearCurrentSelections() {
clearSelections(null);
}
private void clearSelections(Object skipProvider) {
for (SelectionProvider provider:containers) {
if (skipProvider != provider) {
provider.removeSelectionChangeListener(this);
provider.clearCurrentSelections();
provider.addSelectionChangeListener(this);
}
}
}
@Override
public void propertyChange(PropertyChangeEvent evt) {
Collection<View> oldValue = activeSelection;
@SuppressWarnings("unchecked")
Collection<View> newValue = (Collection<View>) evt.getNewValue();
activeSelection = newValue;
assert evt.getNewValue() == activeSelection;
clearSelections(evt.getSource());
pcs.firePropertyChange(SelectionProvider.SELECTION_CHANGED_PROP, oldValue, activeSelection);
}
}