/*
* Copyright 1999-2004 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.cocoon.woody.formmodel;
import org.apache.cocoon.woody.Constants;
import org.apache.cocoon.woody.FormContext;
import org.apache.cocoon.woody.event.WidgetEvent;
import org.apache.cocoon.woody.event.ValueChangedEvent;
import org.apache.cocoon.xml.AttributesImpl;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
import java.util.Locale;
/**
* A widget to select a boolean value. Usually rendered as a checkbox.
*
* <p>You may wonder why we don't use a {@link Field} widget with an associated
* Boolean Datatype instead. The reason is that many of the features of the Field
* widget are overkill for a Boolean: validation is unnecessary (if the field is
* not true it is false), the selectionlist associated with a Datatype also
* has no purpose here (there would always be only 2 choices: true or false),
* and the manner in which the request parameter of this widget is interpreted
* is different (missing or empty request parameter means 'false', rather than null value).
*
* @version $Id: BooleanField.java 30932 2004-07-29 17:35:38Z vgritsenko $
*/
public class BooleanField extends AbstractWidget {
// FIXME(SW) : should the initial value be false or null ? This would allow
// event listeners to be triggered at bind time.
private Boolean value = Boolean.FALSE;
private BooleanFieldDefinition definition;
public BooleanField(BooleanFieldDefinition definition) {
this.definition = definition;
setLocation(definition.getLocation());
}
public String getId() {
return definition.getId();
}
public void readFromRequest(FormContext formContext) {
Object oldValue = value;
String param = formContext.getRequest().getParameter(getFullyQualifiedId());
if (param != null && param.equalsIgnoreCase("true"))
value = Boolean.TRUE;
else
value = Boolean.FALSE;
if (value != oldValue) {
getForm().addWidgetEvent(new ValueChangedEvent(this, oldValue, value));
}
}
/**
* Always return <code>true</code> (an action has no validation)
*
* @todo is there a use case for boolean fields having validators?
*/
public boolean validate(FormContext formContext) {
// a boolean field is always valid
return true;
}
private static final String BOOLEAN_FIELD_EL = "booleanfield";
private static final String VALUE_EL = "value";
public void generateSaxFragment(ContentHandler contentHandler, Locale locale) throws SAXException {
AttributesImpl fieldAttrs = new AttributesImpl();
fieldAttrs.addCDATAAttribute("id", getFullyQualifiedId());
contentHandler.startElement(Constants.WI_NS, BOOLEAN_FIELD_EL, Constants.WI_PREFIX_COLON + BOOLEAN_FIELD_EL, fieldAttrs);
// value element
contentHandler.startElement(Constants.WI_NS, VALUE_EL, Constants.WI_PREFIX_COLON + VALUE_EL, Constants.EMPTY_ATTRS);
String stringValue = String.valueOf(value != null && value.booleanValue() == true? "true": "false");
contentHandler.characters(stringValue.toCharArray(), 0, stringValue.length());
contentHandler.endElement(Constants.WI_NS, VALUE_EL, Constants.WI_PREFIX_COLON + VALUE_EL);
// generate label, help, hint, etc.
definition.generateDisplayData(contentHandler);
contentHandler.endElement(Constants.WI_NS, BOOLEAN_FIELD_EL, Constants.WI_PREFIX_COLON + BOOLEAN_FIELD_EL);
}
public void generateLabel(ContentHandler contentHandler) throws SAXException {
definition.generateLabel(contentHandler);
}
public Object getValue() {
return value;
}
/**
* Sets value of the field. If value is null, it is considered to be false
* (see class comment).
*/
public void setValue(Object object) {
if (object == null) {
object = Boolean.FALSE;
}
if (!(object instanceof Boolean)) {
throw new RuntimeException("Cannot set value of boolean field \"" + getFullyQualifiedId() + "\" to a non-Boolean value.");
}
Object oldValue = value;
value = (Boolean)object;
if (value != oldValue) {
getForm().addWidgetEvent(new ValueChangedEvent(this, oldValue, value));
}
}
public void broadcastEvent(WidgetEvent event) {
this.definition.fireValueChangedEvent((ValueChangedEvent)event);
}
}