com.vaadin.event.dd.acceptcriteria.SourceIsTarget Maven / Gradle / Ivy
/*
* Copyright (C) 2000-2024 Vaadin Ltd
*
* This program is available under Vaadin Commercial License and Service Terms.
*
* See for the full
* 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.ui.Component;
/**
*
* A criterion that ensures the drag source is the same as drop target. E.g.
* {code Tree} or {@code Table} could support only re-ordering of items, but no
* {@link Transferable}s coming outside.
*
* Note! Class is singleton, use {@link #get()} method to get the instance.
*
* @since 6.3
*
*/
public class SourceIsTarget extends ClientSideCriterion {
private static final long serialVersionUID = -451399314705532584L;
private static final SourceIsTarget INSTANCE = new SourceIsTarget();
private SourceIsTarget() {
}
@Override
public boolean accept(DragAndDropEvent dragEvent) {
if (dragEvent.getTransferable() instanceof TransferableImpl) {
Component sourceComponent = dragEvent.getTransferable()
.getSourceComponent();
DropTarget target = dragEvent.getTargetDetails().getTarget();
return sourceComponent == target;
}
return false;
}
public static synchronized SourceIsTarget get() {
return INSTANCE;
}
}