com.vaadin.event.dd.acceptcriteria.ContainsDataFlavor Maven / Gradle / Ivy
/*
* Copyright 2000-2014 Vaadin 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.dd.DragAndDropEvent;
import com.vaadin.server.PaintException;
import com.vaadin.server.PaintTarget;
/**
* A Criterion that checks whether {@link Transferable} contains given data
* flavor. The developer might for example accept the incoming data only if it
* contains "Url" or "Text".
*
* @since 6.3
*/
public class ContainsDataFlavor extends ClientSideCriterion {
private String dataFlavorId;
/**
* Constructs a new instance of {@link ContainsDataFlavor}.
*
* @param dataFlawor
* the type of data that will be checked from
* {@link Transferable}
*/
public ContainsDataFlavor(String dataFlawor) {
dataFlavorId = dataFlawor;
}
@Override
public void paintContent(PaintTarget target) throws PaintException {
super.paintContent(target);
target.addAttribute("p", dataFlavorId);
}
@Override
public boolean accept(DragAndDropEvent dragEvent) {
return dragEvent.getTransferable().getDataFlavors()
.contains(dataFlavorId);
}
@Override
protected String getIdentifier() {
// extending classes use client side implementation from this class
return ContainsDataFlavor.class.getCanonicalName();
}
}