org.apache.cocoon.forms.formmodel
Class BooleanField

java.lang.Object
  org.apache.cocoon.forms.formmodel.AbstractWidget
      org.apache.cocoon.forms.formmodel.BooleanField

All Implemented Interfaces:

ValueChangedListenerEnabled, Widget, ValidationErrorAware, Locatable

public class BooleanField
extends AbstractWidget
implements ValidationErrorAware, ValueChangedListenerEnabled

A widget to select a boolean value. Usually rendered as a checkbox.

You may wonder why we don't use a 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.html 1304258 2012-03-23 10:09:27Z ilgrosso $

Field Summary

protected ValidationError

validationError

Fields inherited from class org.apache.cocoon.forms.formmodel.AbstractWidget

wasValid

Fields inherited from interface org.apache.cocoon.forms.formmodel.Widget

PATH_SEPARATOR

Constructor Summary

BooleanField(BooleanFieldDefinition definition)

Method Summary

void	addValueChangedListener(ValueChangedListener listener) Adds a ValueChangedListener to this widget instance.
void	broadcastEvent(WidgetEvent event) Broadcast an event previously queued by this widget to its event listeners.
void	generateItemSaxFragment(ContentHandler contentHandler, Locale locale) Generates nested additional content nested inside the main element for this widget which is generated by AbstractWidget.generateSaxFragment(ContentHandler, Locale) The implementation on the AbstractWidget level inserts no additional XML.
WidgetDefinition	getDefinition() Concrete subclasses should allow access to their underlaying Definition through this method.
ValidationError	getValidationError() Returns the validation error, if any.
Object	getValue() Get the value of a widget.
protected AttributesImpl	getXMLElementAttributes() The XML attributes used in AbstractWidget.generateSaxFragment(ContentHandler, Locale) to be placed on the wrapping element for all the XML-instance-content of this Widget.
String	getXMLElementName() The XML element name used in AbstractWidget.generateSaxFragment(ContentHandler, Locale) to produce the wrapping element for all the XML-instance-content of this Widget.
boolean	hasValueChangedListeners()
void	initialize() Called after widget's environment has been setup, to allow for any contextual initalization, such as looking up case widgets for union widgets.
void	readFromRequest(FormContext formContext) Lets this widget read its data from a request.
void	removeValueChangedListener(ValueChangedListener listener)
void	setValidationError(ValidationError error) Set a validation error on this field.
void	setValue(Object object) Sets value of the field.

Methods inherited from class org.apache.cocoon.forms.formmodel.AbstractWidget

addValidator, generateDisplayData, generateLabel, generateSaxFragment, getAttribute, getChild, getCombinedState, getForm, getFullName, getId, getLocation, getName, getParent, getRequestParameterName, getState, getWidget, isRequired, isValid, lookupWidget, removeAttribute, removeValidator, setAttribute, setParent, setState, toString, validate, widgetNameChanged

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

validationError

protected ValidationError validationError

Constructor Detail

BooleanField

public BooleanField(BooleanFieldDefinition definition)

Method Detail

getDefinition

public WidgetDefinition getDefinition()

Description copied from class: AbstractWidget

Concrete subclasses should allow access to their underlaying Definition through this method. If subclasses decide to return null they should also organize own implementations of AbstractWidget.getId(), AbstractWidget.getLocation(), AbstractWidget.validate(), AbstractWidget.generateLabel(ContentHandler) and AbstractWidget.generateDisplayData(ContentHandler) to avoid NPE's.

Specified by:

getDefinition in interface Widget

Specified by:

getDefinition in class AbstractWidget

Returns:

the widgetDefinition from which this widget was instantiated. (See WidgetDefinition.createInstance())

initialize

public void initialize()

Description copied from class: AbstractWidget

Called after widget's environment has been setup, to allow for any contextual initalization, such as looking up case widgets for union widgets.

Specified by:

initialize in interface Widget

Overrides:

initialize in class AbstractWidget

readFromRequest

public void readFromRequest(FormContext formContext)

Description copied from interface: Widget

Lets this widget read its data from a request. At this point the Widget may try to convert the request parameter to its native datatype (if it is not a string), but it should not yet generate any validation errors.

Specified by:

readFromRequest in interface Widget

getValidationError

public ValidationError getValidationError()

Returns the validation error, if any. There will always be a validation error in case the AbstractWidget.validate() method returned false.

Specified by:

getValidationError in interface ValidationErrorAware

setValidationError

public void setValidationError(ValidationError error)

Set a validation error on this field. This allows fields to be externally marked as invalid by application logic.

Specified by:

setValidationError in interface ValidationErrorAware

Parameters:

error - the validation error

getXMLElementName

public String getXMLElementName()

Description copied from class: AbstractWidget

The XML element name used in AbstractWidget.generateSaxFragment(ContentHandler, Locale) to produce the wrapping element for all the XML-instance-content of this Widget.

Specified by:

getXMLElementName in class AbstractWidget

Returns:

"booleanfield"

getXMLElementAttributes

protected AttributesImpl getXMLElementAttributes()

Description copied from class: AbstractWidget

The XML attributes used in AbstractWidget.generateSaxFragment(ContentHandler, Locale) to be placed on the wrapping element for all the XML-instance-content of this Widget. This automatically adds @id=AbstractWidget.getRequestParameterName() to that element. Concrete subclasses should call super.getXMLElementAttributes and possibly add additional attributes. Note: the @id is not added for those widgets who's getId() returns null (e.g. top-level container widgets like 'form'). The contract of returning a non-null AttributesImpl is however maintained.

Overrides:

getXMLElementAttributes in class AbstractWidget

Returns:

the attributes for the main element for this widget's sax-fragment.

generateItemSaxFragment

public void generateItemSaxFragment(ContentHandler contentHandler,
                                    Locale locale)
                             throws SAXException

Description copied from class: AbstractWidget

Generates nested additional content nested inside the main element for this widget which is generated by AbstractWidget.generateSaxFragment(ContentHandler, Locale) The implementation on the AbstractWidget level inserts no additional XML. Subclasses need to override to insert widget specific content.

Overrides:

generateItemSaxFragment in class AbstractWidget

Parameters:

contentHandler - to send the SAX events to

locale - in which context potential content needs to be put.

Throws:

SAXException

getValue

public Object getValue()

Description copied from interface: Widget

Get the value of a widget.

Not all widgets do have a value (notably ContainerWidgets, but this method is provided here as a convenience to ease writing and avoiding casts.

Specified by:

getValue in interface Widget

Overrides:

getValue in class AbstractWidget

Returns:

the value of the widget.

setValue

public void setValue(Object object)

Sets value of the field. If value is null, it is considered to be false (see class comment).

Specified by:

setValue in interface Widget

Overrides:

setValue in class AbstractWidget

Parameters:

object - the new widget's value.

addValueChangedListener

public void addValueChangedListener(ValueChangedListener listener)

Adds a ValueChangedListener to this widget instance. Listeners defined on the widget instance will be executed in addtion to any listeners that might have been defined in the widget definition.

Specified by:

addValueChangedListener in interface ValueChangedListenerEnabled

removeValueChangedListener

public void removeValueChangedListener(ValueChangedListener listener)

Specified by:

removeValueChangedListener in interface ValueChangedListenerEnabled

hasValueChangedListeners

public boolean hasValueChangedListeners()

Specified by:

hasValueChangedListeners in interface ValueChangedListenerEnabled

broadcastEvent

public void broadcastEvent(WidgetEvent event)

Description copied from class: AbstractWidget

Broadcast an event previously queued by this widget to its event listeners. Abstract implementation throws a UnsupportedOperationException. Concrete subclass widgets need to override when supporting event broadcasting.

Specified by:

broadcastEvent in interface Widget

Overrides:

broadcastEvent in class AbstractWidget