/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.wicket.protocol.http;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.apache.wicket.Component;
import org.apache.wicket.ajax.AjaxRequestTarget;
import org.apache.wicket.markup.html.internal.InlineEnclosure;
import org.apache.wicket.markup.parser.filter.InlineEnclosureHandler;
import org.apache.wicket.util.visit.IVisit;
import org.apache.wicket.util.visit.IVisitor;
/**
* This listener adds Enclosures to AjaxTarget, where the child controller of the said Enclosure is
* already added. This is a part of the fix to the problem:
*
* "Changing the visibility of a child component in Ajax callback method will not affect the entire
* enclosure but just the child component itself. This is because only the child component is added
* to the AjaxRequestTarget"
*
* When used with an "Inline" Enclosure, this problem is fixed.
*
* Syntax for inline enclosure:
*
* <tr wicket:enclosure="controllingChildId">
*
* In this example the tag used is tr, but any other tag could be used as well. The attribute
* "wicket:enclosure" is mandatory, and is used to recognise an inline enclosure. The value of the
* attribute, here "controllingChildId" can contain an id for the child (controller) element. If the
* said value is not given, the first element inside the enclosure will be used as a controller
* child. If there are no elements inside the enclosure, the parsing will fail.
*
*
* @see WebApplication
* @see InlineEnclosure
* @see InlineEnclosureHandler
*
* @author Joonas Hamalainen
*/
public class AjaxEnclosureListener extends AjaxRequestTarget.AbstractListener
{
/**
* Construct.
*/
public AjaxEnclosureListener()
{
}
/**
* Try to find Enclosures that have their controllers added already, and add them to the target.
*/
@Override
public void onBeforeRespond(final Map<String, Component> map, final AjaxRequestTarget target)
{
final List<String> keysToRemove = new ArrayList<String>();
target.getPage().visitChildren(InlineEnclosure.class, new IVisitor<InlineEnclosure, Void>()
{
@Override
public void component(final InlineEnclosure enclosure, final IVisit<Void> visit)
{
Iterator<Map.Entry<String, Component>> entriesItor = map.entrySet().iterator();
while (entriesItor.hasNext())
{
Map.Entry<String, Component> entry = entriesItor.next();
String componentId = entry.getKey();
Component component = entry.getValue();
if (isControllerOfEnclosure(component, enclosure))
{
enclosure.updateVisibility();
target.add(enclosure);
visit.dontGoDeeper();
keysToRemove.add(componentId);
break;
}
}
}
});
for (String key : keysToRemove)
{
map.remove(key);
}
}
/**
* Check if a given component is the controlling child of a given enclosure
*
* @param component
* @param enclosure
* @return true if the given component is the controlling child of the given InlineEnclosure
*/
private boolean isControllerOfEnclosure(final Component component,
final InlineEnclosure enclosure)
{
return (enclosure.get(enclosure.getChildId()) == component || // #queue()
enclosure.getParent().get(enclosure.getChildId()) == component); // #add()
}
}