/*
* 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.myfaces.custom.tabbedpane;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.el.ValueBinding;
import javax.faces.webapp.UIComponentTag;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.Tag;
import javax.servlet.jsp.tagext.TagSupport;
import org.apache.myfaces.shared_tomahawk.util.ClassUtils;
/**
* Adds a tab-change-listener to the enclosing t:panelTabbedPane component.
* <p>
* When the panelTabbedPane changes the displayed tab, the listener is invoked.
* </p>
*
* @JSFJspTag
* name="t:tabChangeListener"
* bodyContent="empty"
* tagHandler = "org.apache.myfaces.custom.tabbedpane.TabChangeListenerTagHandler"
*
* @author <a href="mailto:oliver@rossmueller.com">Oliver Rossmueller</a>
* @version $Revision: 698966 $ $Date: 2008-09-25 08:41:35 -0500 (Thu, 25 Sep 2008) $
*/
public class TabChangeListenerTag extends TagSupport
{
private static final long serialVersionUID = -6903749011638483023L;
private String type = null;
public TabChangeListenerTag()
{
}
/**
* Define a listener to be attached to the parent HtmlPanelTabbedPane instance.
* <p>
* This attribute may be a literal string containing a fully-qualified class name. The
* specified class must implement the TabChangeListener interface and have a no-arguments
* constructor. A new instance will be created when the view is created.
* </p>
* <p>
* This attribute may also be an EL expression that returns type String. The EL expression will be
* evaluated when the view is built, and the returned value must be a fully-qualified class name. The
* specified class must implement the TabChangeListener interface and have a no-arguments constructor.
* A new instance will be created when the view is created.
* </p>
* <p>
* This attribute may also be an EL expression that returns a TabChangeListener instance.
* </p>
* <p>
* It is an error if an EL expression returns an object of any type other than String or TabChangeListener.
* </p>
*
* @JSFJspAttribute required = "true"
*/
public void setType(String type)
{
this.type = type;
}
public int doStartTag() throws JspException
{
if (type == null)
{
throw new JspException("type attribute not set");
}
//Find parent UIComponentTag
UIComponentTag parentComponentTag = UIComponentTag.getParentUIComponentTag(pageContext);
if (parentComponentTag == null)
{
throw new JspException("TabChangeListenerTag has no UIComponentTag ancestor");
}
if (parentComponentTag.getCreated())
{
//Component was just created, so we add the Listener
UIComponent parent = parentComponentTag.getComponentInstance();
if (parent instanceof HtmlPanelTabbedPane)
{
Object listenerRef = type;
if (UIComponentTag.isValueReference(type))
{
FacesContext facesContext = FacesContext.getCurrentInstance();
ValueBinding valueBinding = facesContext.getApplication().createValueBinding(type);
listenerRef = valueBinding.getValue(facesContext);
}
if(listenerRef instanceof String)
{
String className = (String) listenerRef;
TabChangeListener listener = (TabChangeListener) ClassUtils.newInstance(className);
((HtmlPanelTabbedPane) parent).addTabChangeListener(listener);
}
else if(listenerRef instanceof TabChangeListener)
{
TabChangeListener listener = (TabChangeListener) listenerRef;
((HtmlPanelTabbedPane) parent).addTabChangeListener(listener);
}
else if (listenerRef == null)
{
throw new JspException("Property 'type' must not be null.");
}
else
{
throw new JspException(
"Property 'type' must be either a string (containing a class name) " +
"or a TabChangeListener instance.");
}
}
else
{
throw new JspException(
"Component " + parent.getId() + " is not of type HtmlPanelTabbedPane");
}
}
return Tag.SKIP_BODY;
}
}