/*******************************************************************************
* Copyright 2014 Geoscience Australia
*
* 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.
******************************************************************************/
package au.gov.ga.earthsci.layer.ui;
import java.util.ArrayList;
import java.util.List;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.swt.dnd.DragSourceEvent;
import org.eclipse.swt.dnd.DragSourceListener;
import au.gov.ga.earthsci.layer.tree.ILayerTreeNode;
import au.gov.ga.earthsci.layer.ui.dnd.LayerTransferData;
/**
* {@link DragSourceListener} implementation for the draw order viewer.
*
* @author Michael de Hoog (michael.dehoog@ga.gov.au)
*/
public class DrawOrderDragSourceListener implements DragSourceListener
{
private final TreeViewer viewer;
public DrawOrderDragSourceListener(TreeViewer viewer)
{
this.viewer = viewer;
}
@Override
public void dragStart(DragSourceEvent event)
{
event.doit = false;
IStructuredSelection selection = (IStructuredSelection) viewer.getSelection();
if (selection.isEmpty())
{
return;
}
List<?> selectionList = selection.toList();
for (Object item : selectionList)
{
if (!(item instanceof DrawOrderModel.LayerDrawOrderModelElement))
{
return;
}
}
event.doit = true;
}
@Override
public void dragSetData(DragSourceEvent event)
{
IStructuredSelection selection = (IStructuredSelection) viewer.getSelection();
List<?> selectionList = selection.toList();
List<ILayerTreeNode> nodeList = new ArrayList<ILayerTreeNode>();
for (Object item : selectionList)
{
if (item instanceof DrawOrderModel.LayerDrawOrderModelElement)
{
nodeList.add(((DrawOrderModel.LayerDrawOrderModelElement) item).node);
}
}
ILayerTreeNode[] nodes = nodeList.toArray(new ILayerTreeNode[nodeList.size()]);
LayerTransferData data = LayerTransferData.fromNodes(nodes);
event.data = data;
}
@Override
public void dragFinished(DragSourceEvent event)
{
}
}