wicket.markup.html.form
Class DropDownChoice

java.lang.Object
  wicket.Component
      wicket.MarkupContainer
          wicket.markup.html.WebMarkupContainer
              wicket.markup.html.form.FormComponent
                  wicket.markup.html.form.AbstractChoice
                      wicket.markup.html.form.AbstractSingleSelectChoice
                          wicket.markup.html.form.DropDownChoice

All Implemented Interfaces:

IOnChangeListener, IRequestListener, java.io.Serializable

Direct Known Subclasses:

ListChoice

public class DropDownChoice

extends wicket.markup.html.form.AbstractSingleSelectChoice

implements IOnChangeListener

A choice implemented as a dropdown menu/list. TODO elaborate with an example

You can can extend this class and override method wantOnSelectionChangedNotifications() to force server roundtrips on each selection change.

Author:

Jonathan Locke, Eelco Hillenius, Johan Compagner

See Also:

Serialized Form

Nested Class Summary

Nested classes inherited from class wicket.markup.html.form.FormComponent

FormComponent.IVisitor

Nested classes inherited from class wicket.Component

Component.ComponentModelChange, Component.VisibilityChange

Field Summary

Fields inherited from class wicket.markup.html.form.FormComponent

FLAG_CONVERT_EMPTY_INPUT_STRING_TO_NULL, NO_INVALID_INPUT

Fields inherited from class wicket.Component

FLAG_RESERVED1, FLAG_RESERVED2, FLAG_RESERVED3, FLAG_RESERVED4

Constructor Summary

DropDownChoice(java.lang.String id)

DropDownChoice(java.lang.String id, java.util.Collection choices)

DropDownChoice(java.lang.String id, IChoiceList choices)

DropDownChoice(java.lang.String id, IModel model, java.util.Collection choices)

DropDownChoice(java.lang.String id, IModel model, IChoiceList choices)

Method Summary

protected void	detachModel() Detaches the model for this component if it is detachable.
IChoiceList	getChoices() Gets the list of choices.
protected java.lang.String	getDefaultChoice(java.lang.Object selected)
java.lang.String	getModelValue()
boolean	isNullValid() Is the null value a valid value?
protected boolean	isSelected(IChoice choice) Gets whether the given value represents the current selection.
protected void	onComponentTag(ComponentTag tag) Processes the component tag.
protected void	onComponentTagBody(MarkupStream markupStream, ComponentTag openTag) Handle the container's body.
void	onSelectionChanged() Called when a selection changes.
protected void	onSelectionChanged(java.lang.Object newSelection) Template method that can be overriden by clients that implement IOnChangeListener to be notified by onChange events of a select element.
void	setChoices(IChoiceList choices) Sets the list of choices.
void	setModelValue(java.lang.String value) Sets the value for a form component.
void	setNullValid(boolean nullValid) Is the null value a valid value?
protected boolean	supportsPersistence()
protected void	updateModel() Updates this components' model from the request.
protected boolean	wantOnSelectionChangedNotifications() Whether this component's onSelectionChanged event handler should called using javascript if the selection changes.

Methods inherited from class wicket.markup.html.form.FormComponent

add, getForm, getInput, getValidationType, getValidators, getValue, inputAsInt, inputAsInt, inputAsIntArray, inputAsStringArray, invalid, isPersistent, isValid, isValidated, onInvalid, onModelChanged, onValid, setPersistent, valid, validate

Methods inherited from class wicket.markup.html.WebMarkupContainer

getMarkupType, onRender

Methods inherited from class wicket.MarkupContainer

add, autoAdd, contains, findMarkupStream, get, getMarkupStream, internalAdd, internalBeginRequest, internalEndRequest, iterator, remove, removeAll, renderAssociatedMarkup, renderComponentTagBody, replace, setMarkupStream, setModel, size, toString, toString, visitChildren, visitChildren

Methods inherited from class wicket.Component

add, addStateChange, checkComponentTag, checkComponentTagAttribute, debug, error, exceptionMessage, fatal, findPage, findParent, findParentWithAssociatedMarkup, getApplication, getApplicationPages, getApplicationSettings, getClassRelativePath, getConverter, getEscapeModelStrings, getFeedbackMessage, getFlag, getId, getLocale, getLocalizer, getModel, getModelObject, getModelObjectAsString, getPage, getPageFactory, getPageRelativePath, getParent, getPath, getRenderBodyOnly, getRequest, getRequestCycle, getResource, getResponse, getSession, getString, getString, getString, getStyle, hasErrorMessage, hasFeedbackMessage, info, initModel, internalOnBeginRequest, internalOnEndRequest, internalOnModelChanged, internalOnModelChanging, isAncestorOf, isVersioned, isVisible, isVisibleInHierarchy, modelChanged, modelChanging, newPage, newPage, onBeginRequest, onEndRequest, onModelChanging, onSessionAttach, redirectTo, remove, render, renderComponent, renderComponentTag, rendered, replaceComponentTagBody, sameRootModel, sameRootModel, setFlag, setModelObject, setRedirect, setRenderBodyOnly, setResponsePage, setShouldEscapeModelStrings, setVersioned, setVisible, urlFor, visitParents, warn

Methods inherited from class java.lang.Object

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

Constructor Detail

DropDownChoice

public DropDownChoice(java.lang.String id)

See Also:

AbstractChoice.AbstractChoice(String)

DropDownChoice

public DropDownChoice(java.lang.String id,
                      java.util.Collection choices)

See Also:

AbstractChoice.AbstractChoice(String, Collection)

DropDownChoice

public DropDownChoice(java.lang.String id,
                      IChoiceList choices)

See Also:

AbstractChoice.AbstractChoice(String, IChoiceList)

DropDownChoice

public DropDownChoice(java.lang.String id,
                      IModel model,
                      java.util.Collection choices)

See Also:

AbstractChoice.AbstractChoice(String, IModel, Collection)

DropDownChoice

public DropDownChoice(java.lang.String id,
                      IModel model,
                      IChoiceList choices)

See Also:

AbstractChoice.AbstractChoice(String, IModel, IChoiceList)

Method Detail

onSelectionChanged

public final void onSelectionChanged()

Called when a selection changes.

Specified by:

onSelectionChanged in interface IOnChangeListener

onComponentTag

protected void onComponentTag(ComponentTag tag)

Processes the component tag.

Overrides:

onComponentTag in class FormComponent

Parameters:

tag - Tag to modify

See Also:

Component.onComponentTag(wicket.markup.ComponentTag)

onSelectionChanged

protected void onSelectionChanged(java.lang.Object newSelection)

Template method that can be overriden by clients that implement IOnChangeListener to be notified by onChange events of a select element. This method does nothing by default.

Called when a option is selected of a dropdown list that wants to be notified of this event. This method is to be implemented by clients that want to be notified of selection events.

Parameters:

newSelection - The newly selected object of the backing model NOTE this is the same as you would get by calling getModelObject() if the new selection were current

wantOnSelectionChangedNotifications

protected boolean wantOnSelectionChangedNotifications()

Whether this component's onSelectionChanged event handler should called using javascript if the selection changes. If true, a roundtrip will be generated with each selection change, resulting in the model being updated (of just this component) and onSelectionChanged being called. This method returns false by default.

Returns:

True if this component's onSelectionChanged event handler should called using javascript if the selection changes

getModelValue

public final java.lang.String getModelValue()

Overrides:

getModelValue in class FormComponent

Returns:

Value to return when model value is needed

See Also:

FormComponent.getModelValue()

isNullValid

public boolean isNullValid()

Is the null value a valid value?

Returns:

true when the null value is allowed.

setNullValid

public void setNullValid(boolean nullValid)

Is the null value a valid value?

Parameters:

nullValid - whether null is a valid value

setModelValue

public final void setModelValue(java.lang.String value)

Description copied from class: FormComponent

Sets the value for a form component.

Overrides:

setModelValue in class FormComponent

Parameters:

value - The value

See Also:

FormComponent.setModelValue(java.lang.String)

getDefaultChoice

protected java.lang.String getDefaultChoice(java.lang.Object selected)

Parameters:

selected - The object that's currently selected

Returns:

Any default choice, such as "Choose One", depending on the subclass

See Also:

AbstractChoice.getDefaultChoice(Object)

isSelected

protected boolean isSelected(IChoice choice)

Gets whether the given value represents the current selection.

Parameters:

choice - The choice to check

Returns:

Whether the given value represents the current selection

updateModel

protected final void updateModel()

Updates this components' model from the request.

See Also:

AbstractChoice.updateModel()

getChoices

public IChoiceList getChoices()

Gets the list of choices.

Returns:

The list of choices

setChoices

public final void setChoices(IChoiceList choices)

Sets the list of choices.

Parameters:

choices - the list of choices

detachModel

protected void detachModel()

Description copied from class: Component

Detaches the model for this component if it is detachable.

Overrides:

detachModel in class Component

See Also:

Component.detachModel()

onComponentTagBody

protected void onComponentTagBody(MarkupStream markupStream,
                                  ComponentTag openTag)

Handle the container's body.

Overrides:

onComponentTagBody in class MarkupContainer

Parameters:

markupStream - The markup stream

openTag - The open tag for the body

See Also:

Component.onComponentTagBody(MarkupStream, ComponentTag)

supportsPersistence

protected boolean supportsPersistence()

Overrides:

supportsPersistence in class FormComponent

Returns:

True if this type of FormComponent can be persisted.

See Also:

FormComponent.supportsPersistence()