/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2000-2003 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Apache" and "Apache Software Foundation", "Tapestry"
* must not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* or "Tapestry", nor may "Apache" or "Tapestry" appear in their
* name, without prior written permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE TAPESTRY CONTRIBUTOR COMMUNITY
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.tapestry.form;
import java.io.IOException;
import java.util.Iterator;
import org.apache.tapestry.ApplicationRuntimeException;
import org.apache.tapestry.IActionListener;
import org.apache.tapestry.IBinding;
import org.apache.tapestry.IForm;
import org.apache.tapestry.IMarkupWriter;
import org.apache.tapestry.IRequestCycle;
import org.apache.tapestry.Tapestry;
import org.apache.tapestry.request.RequestContext;
import org.apache.tapestry.util.io.DataSqueezer;
/**
* A specialized component used to edit a list of items
* within a form; it is similar to a {@link org.apache.tapestry.components.Foreach} but leverages
* hidden inputs within the <form> to store the items in the list.
*
* [<a href="../../../../../ComponentReference/ListEdit.html">Component Reference</a>]
*
* @author Howard Lewis Ship
* @version $Id: ListEdit.java,v 1.8 2003/05/28 13:41:36 hlship Exp $
* @since 1.0.2
*
**/
public abstract class ListEdit extends AbstractFormComponent
{
protected void renderComponent(IMarkupWriter writer, IRequestCycle cycle)
{
Iterator i = null;
IForm form = getForm(cycle);
boolean cycleRewinding = cycle.isRewinding();
// If the cycle is rewinding, but not this particular form,
// then do nothing (don't even render the body).
if (cycleRewinding && !form.isRewinding())
return;
String name = form.getElementId(this);
if (!cycleRewinding)
{
i = Tapestry.coerceToIterator(getSourceBinding().getObject());
}
else
{
RequestContext context = cycle.getRequestContext();
String[] submittedValues = context.getParameters(name);
i = Tapestry.coerceToIterator(submittedValues);
}
// If the source (when rendering), or the submitted values (on submit)
// are null, then skip the remainder (nothing to update, nothing to
// render).
if (i == null)
return;
int index = 0;
IBinding indexBinding = getIndexBinding();
IBinding valueBinding = getValueBinding();
IActionListener listener = getListener();
String element = getElement();
while (i.hasNext())
{
Object value = null;
if (indexBinding != null)
indexBinding.setInt(index++);
if (cycleRewinding)
value = convertValue((String) i.next());
else
{
value = i.next();
writeValue(form, name, value);
}
valueBinding.setObject(value);
if (listener != null)
listener.actionTriggered(this, cycle);
if (element != null)
{
writer.begin(element);
renderInformalParameters(writer, cycle);
}
renderBody(writer, cycle);
if (element != null)
writer.end();
}
}
private void writeValue(IForm form, String name, Object value)
{
String externalValue;
try
{
externalValue = getDataSqueezer().squeeze(value);
}
catch (IOException ex)
{
throw new ApplicationRuntimeException(
Tapestry.format("ListEdit.unable-to-convert-value", value),
this,
ex);
}
form.addHiddenValue(name, externalValue);
}
private Object convertValue(String value)
{
try
{
return getDataSqueezer().unsqueeze(value);
}
catch (IOException ex)
{
throw new ApplicationRuntimeException(
Tapestry.format("ListEdit.unable-to-convert-string", value),
this,
ex);
}
}
public abstract String getElement();
private DataSqueezer getDataSqueezer()
{
return getPage().getEngine().getDataSqueezer();
}
/** @since 2.2 **/
public abstract IActionListener getListener();
/** @since 3.0 **/
public abstract IBinding getSourceBinding();
public abstract IBinding getValueBinding();
public abstract IBinding getIndexBinding();
/** @since 3.0 **/
public boolean isDisabled()
{
return false;
}
}