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.ajax.markup.html.modal;
018
019import org.apache.wicket.Component;
020import org.apache.wicket.behavior.Behavior;
021import org.apache.wicket.core.util.string.CssUtils;
022import org.apache.wicket.markup.head.IHeaderResponse;
023import org.apache.wicket.markup.head.JavaScriptHeaderItem;
024import org.apache.wicket.markup.head.OnDomReadyHeaderItem;
025import org.apache.wicket.markup.head.PriorityHeaderItem;
026import org.apache.wicket.request.resource.JavaScriptResourceReference;
027import org.apache.wicket.request.resource.ResourceReference;
028
029/**
030 * Trap focus inside a component's markup.
031 * 
032 * @author svenmeier
033 */
034public class TrapFocusBehavior extends Behavior
035{
036
037        /**
038         * Resource key for a CSS class to be applied to the current active focus-trap. 
039         */
040        public static final String CSS_CURRENT_KEY = CssUtils.key(TrapFocusBehavior.class, "current");
041
042        private static final long serialVersionUID = 1L;
043        
044        private static final ResourceReference JS = new JavaScriptResourceReference(
045                TrapFocusBehavior.class, "trap-focus.js");
046
047        @Override
048        public void renderHead(Component component, IHeaderResponse response)
049        {
050                response.render(JavaScriptHeaderItem.forReference(JS));
051                
052                String styleClass = component.getString(CSS_CURRENT_KEY, null, "current-focus-trap");
053                
054                CharSequence script = String.format("Wicket.trapFocus('%s', '%s');", component.getMarkupId(), styleClass);
055                
056                response.render(new PriorityHeaderItem(OnDomReadyHeaderItem.forScript(script)));
057        }
058}