/*
* Copyright 2010 IT Mill Ltd.
*
* 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 com.vaadin.event.dd.acceptcriteria;
import com.vaadin.event.Transferable;
import com.vaadin.event.TransferableImpl;
import com.vaadin.event.dd.DragAndDropEvent;
import com.vaadin.event.dd.DropTarget;
import com.vaadin.terminal.gwt.client.ui.dd.VSourceIsTarget;
import com.vaadin.ui.Component;
import com.vaadin.ui.Table;
import com.vaadin.ui.Tree;
/**
*
* A criterion that ensures the drag source is the same as drop target. Eg.
* {@link Tree} or {@link Table} could support only re-ordering of items, but no
* {@link Transferable}s coming outside.
* <p>
* Note! Class is singleton, use {@link #get()} method to get the instance.
*
* @since 6.3
*
*/
@ClientCriterion(VSourceIsTarget.class)
public class SourceIsTarget extends ClientSideCriterion {
private static final long serialVersionUID = -451399314705532584L;
private static SourceIsTarget instance = new SourceIsTarget();
private SourceIsTarget() {
}
public boolean accept(DragAndDropEvent dragEvent) {
if (dragEvent.getTransferable() instanceof TransferableImpl) {
Component sourceComponent = ((TransferableImpl) dragEvent
.getTransferable()).getSourceComponent();
DropTarget target = dragEvent.getTargetDetails().getTarget();
return sourceComponent == target;
}
return false;
}
public static synchronized SourceIsTarget get() {
return instance;
}
}