org.apache.cocoon.forms.formmodel
Class MultiValueField

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

All Implemented Interfaces:

ValueChangedListenerEnabled, DataWidget, SelectableWidget, Widget, ValidationErrorAware, Locatable

public class MultiValueField
extends AbstractWidget
implements ValidationErrorAware, SelectableWidget, DataWidget, ValueChangedListenerEnabled

A MultiValueField is mostly the same as a normal Field, but can hold multiple values. A MultiValueField should have a Datatype which has a SelectionList, because the user will always select the values from a list. A MultiValueField has no concept of "required", you should instead use the ValueCountValidationRule to check how many items the user has selected.

A MultiValueField also has a Datatype associated with it. In case of MultiValueFields, this Datatype will always be an array type, thus Datatype.isArrayType() will always return true, and this in return has an influence on the kind of validation rules that can be used with the Datatype (see Datatype description for more information).

Version:

$Id: MultiValueField.html 1304258 2012-03-23 10:09:27Z ilgrosso $

Field Summary

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

MultiValueField(MultiValueFieldDefinition definition)

Method Summary

void	addValueChangedListener(ValueChangedListener listener)
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.
Datatype	getDatatype()
WidgetDefinition	getDefinition() Concrete subclasses should allow access to their underlaying Definition through this method.
ValidationError	getValidationError()
Object	getValue() Get the value of a 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	setSelectionList(Object model, String valuePath, String labelPath) Set this field's selection list using values from an in-memory object.
void	setSelectionList(SelectionList selectionList) Set this field's selection list.
void	setSelectionList(String uri) Read this field's selection list from an external source.
void	setValidationError(ValidationError error)
void	setValue(Object value) Sets the value of this widget.
void	setValues(Object[] values)
boolean	validate() Validates this widget and returns the outcome.

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, getXMLElementAttributes, isRequired, isValid, lookupWidget, removeAttribute, removeValidator, setAttribute, setParent, setState, toString, widgetNameChanged

Methods inherited from class java.lang.Object

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

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

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

Constructor Detail

MultiValueField

public MultiValueField(MultiValueFieldDefinition definition)

Method Detail

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

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())

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

validate

public boolean validate()

Description copied from interface: Widget

Validates this widget and returns the outcome. Possible error messages are remembered by the widget itself and will be part of the XML produced by this widget in its Widget.generateSaxFragment(ContentHandler, Locale) method.

Specified by:

validate in interface Widget

Overrides:

validate in class AbstractWidget

Returns:

true to indicate all validations were ok, false otherwise

See Also:

Widget.validate()

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:

"multivaluefield"

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 value)

Description copied from interface: Widget

Sets the value of this 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:

setValue in interface Widget

Overrides:

setValue in class AbstractWidget

Parameters:

value - the new widget's value.

setValues

public void setValues(Object[] values)

setSelectionList

public void setSelectionList(SelectionList selectionList)

Set this field's selection list.

Specified by:

setSelectionList in interface SelectableWidget

Parameters:

selectionList - The new selection list.

setSelectionList

public void setSelectionList(String uri)

Read this field's selection list from an external source. All Cocoon-supported protocols can be used. The format of the XML produced by the source should be the same as in case of inline specification of the selection list, thus the root element should be a fd:selection-list element.

Specified by:

setSelectionList in interface SelectableWidget

Parameters:

uri - The URI of the source.

setSelectionList

public void setSelectionList(Object model,
                             String valuePath,
                             String labelPath)

Set this field's selection list using values from an in-memory object. The object parameter should point to a collection (Java collection or array, or Javascript array) of objects. Each object belonging to the collection should have a value property and a label property, whose values are used to specify the value attribute and the contents of the fd:label child element of every fd:item in the list.

Access to the values of the above mentioned properties is done via XPath expressions.

Specified by:

setSelectionList in interface SelectableWidget

Parameters:

model - The collection used as a model for the selection list.

valuePath - An XPath expression referring to the attribute used to populate the values of the list's items.

labelPath - An XPath expression referring to the attribute used to populate the labels of the list's items.

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

getValidationError

public ValidationError getValidationError()

Specified by:

getValidationError in interface ValidationErrorAware

setValidationError

public void setValidationError(ValidationError error)

Specified by:

setValidationError in interface ValidationErrorAware

getDatatype

public Datatype getDatatype()

Specified by:

getDatatype in interface DataWidget

addValueChangedListener

public void addValueChangedListener(ValueChangedListener listener)

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