001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.wicket.extensions.breadcrumb; 018 019import org.apache.wicket.Component; 020import org.apache.wicket.extensions.breadcrumb.panel.BreadCrumbPanel; 021import org.apache.wicket.model.IModel; 022import org.apache.wicket.util.io.IClusterable; 023 024 025/** 026 * Bread crumb participants function as proxies for components that are part of a bread crumb 027 * hierarchy. An example of a bread crumb is: 028 * 029 * <pre> 030 * Home > Products & Solutions > Hardware > Desktop Systems 031 * </pre> 032 * 033 * In a {@link BreadCrumbPanel panel based implementation}, <tt>Home</tt>, 034 * <tt>Products & Solutions</tt> etc would be separate panels that all are bread crumb 035 * participants: for instance the <tt>Home</tt> participant's {@link #getTitle() title} would return 036 * 'Home', and {@link #getComponent() the component} would be the corresponding panel. 037 * 038 * @author Eelco Hillenius 039 */ 040public interface IBreadCrumbParticipant extends IClusterable 041{ 042 /** 043 * Gets the participating component. Typically, this is a panel. 044 * 045 * @return The participating component, must return a non-null value 046 */ 047 Component getComponent(); 048 049 /** 050 * Gets the title of the bread crumb, which will be used for displaying it. 051 * 052 * @return The title of the bread crumb 053 */ 054 IModel<String> getTitle(); 055 056 /** 057 * Called when the corresponding bread crumb is activated. 058 * 059 * @param previous 060 * The previously active bread crumb participant, possibly null 061 */ 062 void onActivate(IBreadCrumbParticipant previous); 063}