// Copyright 2004, 2005 The Apache Software Foundation
//
// Licensed 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.tapestry.form;
import org.apache.tapestry.IForm;
import org.apache.tapestry.IMarkupWriter;
import org.apache.tapestry.IRequestCycle;
/**
* Implements a component that manages an HTML <input type=checkbox> form element. [ <a
* href="../../../../../ComponentReference/Checkbox.html">Component Reference </a>]
*
* @author Howard Lewis Ship
*/
public abstract class Checkbox extends AbstractFormComponent
{
/**
* Renders the form elements, or responds when the form containing the element is submitted (by
* checking {@link Form#isRewinding()}.
* <p>
* In traditional HTML, many checkboxes would have the same name but different values. Under
* Tapestry, it makes more sense to have different names and a fixed value. For a checkbox, we
* only care about whether the name appears as a request parameter.
*/
protected void renderComponent(IMarkupWriter writer, IRequestCycle cycle)
{
IForm form = getForm(cycle);
if (form.wasPrerendered(writer, this))
return;
// Used whether rewinding or not.
String name = form.getElementId(this);
if (form.isRewinding())
{
String value = cycle.getParameter(name);
setSelected((value != null));
return;
}
writer.beginEmpty("input");
writer.attribute("type", "checkbox");
writer.attribute("name", name);
if (isDisabled())
writer.attribute("disabled", "disabled");
if (isSelected())
writer.attribute("checked", "checked");
renderInformalParameters(writer, cycle);
writer.closeTag();
}
public abstract boolean isDisabled();
/** @since 2.2 * */
public abstract boolean isSelected();
/** @since 2.2 * */
public abstract void setSelected(boolean selected);
}