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; import java.lang.reflect.Method; import com.vaadin.ui.Component; import com.vaadin.util.ReflectTools; /** * An event that is fired when an item is collapsed in a listing component that * displays hierarchical data. Note that expanded subtrees of the collapsed item * will not trigger collapse events. * * @author Vaadin Ltd * @since 8.1 * @param <T> * collapsed item type */ public class CollapseEvent<T> extends Component.Event implements HasUserOriginated { private final T collapsedItem; private final boolean userOriginated; /** * Construct a collapse event. * * @param source * the hierarchical component this event originated from * @param collapsedItem * the item that was collapsed * @param userOriginated * whether the collapse was triggered by a user interaction or * the server */ public CollapseEvent(Component source, T collapsedItem, boolean userOriginated) { super(source); this.collapsedItem = collapsedItem; this.userOriginated = userOriginated; } /** * Get the collapsed item that triggered this event. * * @return the collapsed item */ public T getCollapsedItem() { return collapsedItem; } @Override public boolean isUserOriginated() { return userOriginated; } /** * Item collapse event listener. * * @param <T> * the collapsed item's type * @since 8.1 */ @FunctionalInterface public interface CollapseListener<T> extends SerializableEventListener { public static final Method COLLAPSE_METHOD = ReflectTools.findMethod(CollapseListener.class, "itemCollapse", CollapseEvent.class); /** * Callback method for when an item has been collapsed. * * @param event * the collapse event */ public void itemCollapse(CollapseEvent<T> event); } }