Java tutorial
/* * Copyright 2000-2018 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.dd.DragAndDropEvent; import com.vaadin.event.dd.TargetDetails; import com.vaadin.server.PaintException; import com.vaadin.server.PaintTarget; /** * Criterion for checking if drop target details contains the specific property * with the specific value. Currently only String values are supported. * * @since 6.3 * * TODO add support for other basic data types that we support in UIDL. * */ public class TargetDetailIs extends ClientSideCriterion { private static final long serialVersionUID = 763165450054331246L; private String propertyName; private Object value; /** * Constructs a criterion which ensures that the value there is a value in * {@link TargetDetails} that equals the reference value. * * @param dataFlavor * the type of data to be checked * @param value * the reference value to which the drop target detail will be * compared */ public TargetDetailIs(String dataFlavor, String value) { propertyName = dataFlavor; this.value = value; } public TargetDetailIs(String dataFlavor, Boolean true1) { propertyName = dataFlavor; value = true1; } @Override public void paintContent(PaintTarget target) throws PaintException { super.paintContent(target); target.addAttribute("p", propertyName); if (value instanceof Boolean) { target.addAttribute("v", ((Boolean) value).booleanValue()); target.addAttribute("t", "b"); } else if (value instanceof String) { target.addAttribute("v", (String) value); } } @Override public boolean accept(DragAndDropEvent dragEvent) { Object data = dragEvent.getTargetDetails().getData(propertyName); return value.equals(data); } @Override protected String getIdentifier() { // sub classes by default use VDropDetailEquals a client implementation return TargetDetailIs.class.getCanonicalName(); } }