org.zkoss.zul
Class Combobox

java.lang.Object
  org.zkoss.zk.ui.AbstractComponent
      org.zkoss.zk.ui.HtmlBasedComponent
          org.zkoss.zul.impl.XulElement
              org.zkoss.zul.impl.InputElement
                  org.zkoss.zul.Textbox
                      org.zkoss.zul.Combobox

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, Component, Disable, Readonly, Scope, ComponentCtrl, Constrainted

public class Combobox
extends Textbox

A combobox.

Non-XUL extension. It is used to replace XUL menulist. This class is more flexible than menulist, such as setAutocomplete(boolean) setAutodrop(boolean).

Default getZclass(): z-combobox.(since 3.5.0)

Events: onOpen, onSelect, onAfterRender
Developers can listen to the onOpen event and initializes it when OpenEvent.isOpen() is true, and/or clean up if false.
onAfterRender is sent when the model's data has been rendered.(since 5.0.4)

Besides assign a list model, you could assign a renderer (a ComboitemRenderer instance) to a combobox, such that the combobox will use this renderer to render the data returned by ListModel.getElementAt(int). If not assigned, the default renderer, which assumes a label per combo item, is used. In other words, the default renderer adds a label to a row by calling toString against the object returned by ListModel.getElementAt(int). (since 3.0.2)

Note: to have better performance, onOpen is sent only if a non-deferrable event listener is registered (see Deferrable).

Like Datebox, the value of a read-only comobobox (InputElement.isReadonly()) can be changed by dropping down the list and selecting an combo item (though users cannot type anything in the input box).

Author:

tomyeh

See Also:

Comboitem, Serialized Form

Nested Class Summary

protected class

Combobox.ExtraCtrl A utility class to implement HtmlBasedComponent.getExtraCtrl().

Nested classes/interfaces inherited from class org.zkoss.zk.ui.AbstractComponent

AbstractComponent.Children

Field Summary

Fields inherited from class org.zkoss.zul.impl.InputElement

_value

Fields inherited from class org.zkoss.zk.ui.HtmlBasedComponent

_zclass

Fields inherited from interface org.zkoss.zk.ui.Component

APPLICATION_SCOPE, COMPONENT_SCOPE, DESKTOP_SCOPE, PAGE_SCOPE, REQUEST_SCOPE, SESSION_SCOPE, SPACE_SCOPE

Fields inherited from interface org.zkoss.zk.ui.sys.ComponentCtrl

CE_BUSY_IGNORE, CE_DUPLICATE_IGNORE, CE_IMPORTANT, CE_NON_DEFERRABLE, CE_REPEAT_IGNORE

Constructor Summary

Combobox()

Combobox(java.lang.String value)

Method Summary

Comboitem	appendItem(java.lang.String label) Appends an item.
void	beforeChildAdded(Component newChild, Component refChild) Default: does nothing.
java.lang.Object	clone() Clones the component.
void	close() Closes the list of combo items (Comboitem if it was dropped down.
protected java.lang.String	coerceToString(java.lang.Object value) Coerces the value passed to Textbox.setValue(java.lang.String).
java.lang.Object	getExtraCtrl() Returns the client control for this component.
Comboitem	getItemAtIndex(int index) Returns the item at the specified index.
int	getItemCount() Returns the number of items.
<T> ComboitemRenderer<T>	getItemRenderer() Returns the renderer to render each row, or null if the default renderer is used.
java.util.List<Comboitem>	getItems() Returns a 'live' list of all Comboitem.
<T> ListModel<T>	getModel() Returns the list model associated with this combobox, or null if this combobox is not associated with any list data model.
int	getSelectedIndex() Returns the index of the selected item, or -1 if not selected.
Comboitem	getSelectedItem() Returns the selected item.
java.lang.String	getZclass() Returns the ZK Cascading Style class(es) for this component.
boolean	isAutocomplete() Returns whether to automatically complete this text box by matching the nearest item (Comboitem.
boolean	isAutodrop() Returns whether to automatically drop the list if users is changing this text box.
boolean	isButtonVisible() Returns whether the button (on the right of the textbox) is visible.
protected boolean	isChildable() Childable.
boolean	isOpen() Returns whether this combobox is open.
void	onChildAdded(Component child) Default: does nothing.
void	onChildRemoved(Component child) Default: does nothing.
void	onInitRender(Event data) Handles a private event, onInitRender.
void	open() Drops down the list of combo items (Comboitem.
Comboitem	removeItemAt(int index) Removes the child item in the list box at the given index.
protected void	renderProperties(ContentRenderer renderer) Renders the content of this component, excluding the enclosing tags and children.
void	service(AuRequest request, boolean everError) Processes an AU request.
void	sessionDidActivate(Page page) Notification that the session, which owns this component, has just been activated (a.k.a., deserialized).
void	sessionWillPassivate(Page page) Notification that the session, which owns this component, is about to be passivated (a.k.a., serialized).
void	setAutocomplete(boolean autocomplete) Sets whether to automatically complete this text box by matching the nearest item (Comboitem.
void	setAutodrop(boolean autodrop) Sets whether to automatically drop the list if users is changing this text box.
void	setButtonVisible(boolean visible) Sets whether the button (on the right of the textbox) is visible.
void	setItemRenderer(ComboitemRenderer<?> renderer) Sets the renderer which is used to render each row if getModel() is not null.
void	setItemRenderer(java.lang.String clsnm) Sets the renderer by use of a class name.
void	setModel(ListModel<?> model) Sets the list model associated with this combobox.
void	setMultiline(boolean multiline) Sets whether it is multiline.
void	setOpen(boolean open) Drops down or closes the list of combo items (Comboitem.
void	setRows(int rows) Sets the rows.
void	setSelectedIndex(int jsel) Deselects the currently selected items and selects the item with the given index.
void	setSelectedItem(Comboitem item) Deselects the currently selected items and selects the given item.

Methods inherited from class org.zkoss.zul.Textbox

coerceFromString, getRows, getType, getValue, isMultiline, isTabbable, setTabbable, setType, setValue

Methods inherited from class org.zkoss.zul.impl.InputElement

checkUserError, clearErrorMessage, clearErrorMessage, getCols, getConstraint, getErrorMessage, getInstant, getMaxlength, getName, getPlaceholder, getRawText, getRawValue, getTabindex, getTargetValue, getText, isDisabled, isInplace, isReadonly, isValid, marshall, onWrongValue, select, setCols, setConstraint, setConstraint, setDisabled, setErrorMessage, setInplace, setInstant, setMaxlength, setName, setPlaceholder, setRawValue, setReadonly, setSelectedText, setSelectionRange, setTabindex, setText, setValueDirectly, showCustomError, unmarshall, validate

Methods inherited from class org.zkoss.zul.impl.XulElement

getContext, getCtrlKeys, getPopup, getTooltip, setContext, setContext, setCtrlKeys, setPopup, setPopup, setTooltip, setTooltip

Methods inherited from class org.zkoss.zk.ui.HtmlBasedComponent

focus, getAction, getDraggable, getDroppable, getHeight, getHflex, getLeft, getRenderdefer, getSclass, getStyle, getTooltiptext, getTop, getVflex, getWidth, getZindex, getZIndex, setAction, setClass, setDraggable, setDroppable, setFocus, setHeight, setHeightDirectly, setHflex, setHflexDirectly, setLeft, setLeftDirectly, setRenderdefer, setSclass, setStyle, setTooltiptext, setTop, setTopDirectly, setVflex, setWidth, setWidthDirectly, setZclass, setZindex, setZIndex, setZIndexDirectly

Methods inherited from class org.zkoss.zk.ui.AbstractComponent

addAnnotation, addAnnotation, addClientEvent, addEventHandler, addEventListener, addEventListener, addForward, addForward, addForward, addForward, addMoved, addScopeListener, addSharedEventHandlerMap, appendChild, applyProperties, beforeChildRemoved, beforeParentChanged, detach, didActivate, didActivate, didDeserialize, didDeserialize, disableClientUpdate, equals, getAnnotatedProperties, getAnnotatedPropertiesBy, getAnnotation, getAnnotation, getAnnotations, getAnnotations, getAnnotations, getAttribute, getAttribute, getAttribute, getAttributeOrFellow, getAttributes, getAttributes, getAuService, getAutag, getChildren, getClientEvents, getDefaultMold, getDefinition, getDesktop, getEventHandler, getEventHandlerNames, getEventListenerMap, getEventListeners, getFellow, getFellow, getFellowIfAny, getFellowIfAny, getFellows, getFirstChild, getId, getLastChild, getListenerIterator, getMold, getNextSibling, getPage, getParent, getPreviousSibling, getRoot, getSpaceOwner, getStubonly, getTemplate, getTemplateNames, getUuid, getWidgetAttribute, getWidgetAttributeNames, getWidgetClass, getWidgetListener, getWidgetListenerNames, getWidgetOverride, getWidgetOverrideNames, hasAttribute, hasAttribute, hasAttribute, hasAttributeOrFellow, hasFellow, hasFellow, insertBefore, invalidate, isInvalidated, isListenerAvailable, isVisible, onPageAttached, onPageDetached, query, queryAll, redraw, redrawChildren, removeAttribute, removeAttribute, removeAttribute, removeChild, removeEventListener, removeForward, removeForward, removeScopeListener, render, render, render, replace, response, response, response, service, setAttribute, setAttribute, setAttribute, setAuService, setAutag, setDefinition, setDefinition, setId, setMold, setPage, setPageBefore, setParent, setStubonly, setStubonly, setTemplate, setVisible, setVisibleDirectly, setWidgetAttribute, setWidgetClass, setWidgetListener, setWidgetOverride, smartUpdate, smartUpdate, smartUpdate, smartUpdate, smartUpdate, smartUpdate, smartUpdate, smartUpdate, smartUpdate, smartUpdateWidgetListener, smartUpdateWidgetOverride, toString, updateByClient, willPassivate, willPassivate, willSerialize, willSerialize

Methods inherited from class java.lang.Object

finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Combobox

public Combobox()

Combobox

public Combobox(java.lang.String value)
         throws WrongValueException

Throws:

WrongValueException

Method Detail

coerceToString

protected java.lang.String coerceToString(java.lang.Object value)

Description copied from class: Textbox

Coerces the value passed to Textbox.setValue(java.lang.String).

Default: convert null to an empty string.

Overrides:

coerceToString in class Textbox

getModel

public <T> ListModel<T> getModel()

Returns the list model associated with this combobox, or null if this combobox is not associated with any list data model.

Note: for implementation of auto-complete, the result of getItemCount() is a subset of model. So, if the model implemented ListSubModel interface, you can't use the index of model to find the comboitem by getItemAtIndex(int).

Since:

3.0.2

See Also:

ListSubModel.getSubModel(Object, int)

setModel

public void setModel(ListModel<?> model)

Sets the list model associated with this combobox. If a non-null model is assigned, no matter whether it is the same as the previous, it will always cause re-render.

Parameters:

model - the list model to associate, or null to dissociate any previous model.

Throws:

UiException - if failed to initialize with the model

Since:

3.0.2

getItemRenderer

public <T> ComboitemRenderer<T> getItemRenderer()

Returns the renderer to render each row, or null if the default renderer is used.

Since:

3.0.2

setItemRenderer

public void setItemRenderer(ComboitemRenderer<?> renderer)

Sets the renderer which is used to render each row if getModel() is not null.

Note: changing a render will not cause the combobox to re-render. If you want it to re-render, you could assign the same model again (i.e., setModel(getModel())), or fire an ListDataEvent event.

Parameters:

renderer - the renderer, or null to use the default.

Throws:

UiException - if failed to initialize with the model

Since:

3.0.2

setItemRenderer

public void setItemRenderer(java.lang.String clsnm)
                     throws java.lang.ClassNotFoundException,
                            java.lang.NoSuchMethodException,
                            java.lang.IllegalAccessException,
                            java.lang.InstantiationException,
                            java.lang.reflect.InvocationTargetException

Sets the renderer by use of a class name. It creates an instance automatically.

Throws:

java.lang.ClassNotFoundException

java.lang.NoSuchMethodException

java.lang.IllegalAccessException

java.lang.InstantiationException

java.lang.reflect.InvocationTargetException

Since:

3.0.2

onInitRender

public void onInitRender(Event data)

Handles a private event, onInitRender. It is used only for implementation, and you rarely need to invoke it explicitly.

Since:

3.0.2

isAutodrop

public boolean isAutodrop()

Returns whether to automatically drop the list if users is changing this text box.

Default: false.

setAutodrop

public void setAutodrop(boolean autodrop)

Sets whether to automatically drop the list if users is changing this text box.

isAutocomplete

public boolean isAutocomplete()

Returns whether to automatically complete this text box by matching the nearest item (Comboitem. It is also known as auto-type-ahead.

Default: true (since 5.0.0).

If true, the nearest item will be searched and the text box is updated automatically. If false, user has to click the item or use the DOWN or UP keys to select it back.

Don't confuse it with the auto-completion feature mentioned by other framework. Such kind of auto-completion is supported well by listening to the onChanging event.

setAutocomplete

public void setAutocomplete(boolean autocomplete)

Sets whether to automatically complete this text box by matching the nearest item (Comboitem.

isOpen

public boolean isOpen()

Returns whether this combobox is open.

Default: false.

Since:

6.0.0

setOpen

public void setOpen(boolean open)

Drops down or closes the list of combo items (Comboitem. only works while visible

Since:

3.0.1

See Also:

open(), close()

open

public void open()

Drops down the list of combo items (Comboitem. It is the same as setOpen(true).

Since:

3.0.1

close

public void close()

Closes the list of combo items (Comboitem if it was dropped down. It is the same as setOpen(false).

Since:

3.0.1

isButtonVisible

public boolean isButtonVisible()

Returns whether the button (on the right of the textbox) is visible.

Default: true.

setButtonVisible

public void setButtonVisible(boolean visible)

Sets whether the button (on the right of the textbox) is visible.

getItems

public java.util.List<Comboitem> getItems()

Returns a 'live' list of all Comboitem. By live we mean you can add or remove them directly with the List interface.

Currently, it is the same as AbstractComponent.getChildren(). However, we might add other kind of children in the future.

getItemCount

public int getItemCount()

Returns the number of items.

getItemAtIndex

public Comboitem getItemAtIndex(int index)

Returns the item at the specified index.

appendItem

public Comboitem appendItem(java.lang.String label)

Appends an item.

removeItemAt

public Comboitem removeItemAt(int index)

Removes the child item in the list box at the given index.

Returns:

the removed item.

getSelectedItem

public Comboitem getSelectedItem()

Returns the selected item.

Since:

2.4.0

setSelectedItem

public void setSelectedItem(Comboitem item)

Deselects the currently selected items and selects the given item.

Note: if the label of comboitem has the same more than one, the first comboitem will be selected at client side, it is a limitation of Combobox and it is different from Listbox.

Since:

3.0.2

setSelectedIndex

public void setSelectedIndex(int jsel)

Deselects the currently selected items and selects the item with the given index.

Note: if the label of comboitem has the same more than one, the first comboitem will be selected at client side, it is a limitation of Combobox and it is different from Listbox.

Since:

3.0.2

getSelectedIndex

public int getSelectedIndex()

Returns the index of the selected item, or -1 if not selected.

Since:

3.0.1

setMultiline

public void setMultiline(boolean multiline)

Description copied from class: Textbox

Sets whether it is multiline.

Overrides:

setMultiline in class Textbox

setRows

public void setRows(int rows)

Description copied from class: Textbox

Sets the rows.

Overrides:

setRows in class Textbox

getExtraCtrl

public java.lang.Object getExtraCtrl()

Description copied from class: HtmlBasedComponent

Returns the client control for this component. It is used only by component developers.

Default: creates an instance of HtmlBasedComponent.ExtraCtrl.

Specified by:

getExtraCtrl in interface ComponentCtrl

Overrides:

getExtraCtrl in class HtmlBasedComponent

Returns:

null if no special handling required. If the component requires some special controls, it could return an object that implements one or several interfaces in the org.zkoss.zk.ui.ext.render package. For example, Cropper.

See Also:

ComponentCtrl.getExtraCtrl()

getZclass

public java.lang.String getZclass()

Description copied from class: HtmlBasedComponent

Returns the ZK Cascading Style class(es) for this component. It usually depends on the implementation of the mold (@{link #getMold}).

Default: null (the default value depends on element).

HtmlBasedComponent.setZclass(java.lang.String)) will completely replace the default style of a component. In other words, the default style of a component is associated with the default value of HtmlBasedComponent.getZclass(). Once it is changed, the default style won't be applied at all. If you want to perform small adjustments, use HtmlBasedComponent.setSclass(java.lang.String) instead.

Overrides:

getZclass in class Textbox

See Also:

HtmlBasedComponent.getSclass()

renderProperties

protected void renderProperties(ContentRenderer renderer)
                         throws java.io.IOException

Description copied from class: HtmlBasedComponent

Renders the content of this component, excluding the enclosing tags and children.

See also ZK Client-side Reference: Property Rendering

Overrides:

renderProperties in class Textbox

Throws:

java.io.IOException

service

public void service(AuRequest request,
                    boolean everError)

Processes an AU request.

Default: in addition to what are handled by InputElement.service(org.zkoss.zk.au.AuRequest, boolean), it also handles onOpen and onSelect.

Specified by:

service in interface ComponentCtrl

Overrides:

service in class InputElement

everError - whether any error ever occurred before processing this request.

Since:

5.0.0

See Also:

AbstractComponent.setAuService(org.zkoss.zk.au.AuService)

beforeChildAdded

public void beforeChildAdded(Component newChild,
                             Component refChild)

Description copied from class: AbstractComponent

Default: does nothing.

Specified by:

beforeChildAdded in interface ComponentCtrl

Overrides:

beforeChildAdded in class AbstractComponent

Parameters:

newChild - the child to be added (never null).

refChild - another child component that the new child will be inserted before it. If null, the new child will be the last child.

See Also:

ComponentCtrl.beforeChildAdded(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component)

isChildable

protected boolean isChildable()

Childable.

Overrides:

isChildable in class InputElement

onChildAdded

public void onChildAdded(Component child)

Description copied from class: AbstractComponent

Default: does nothing.

Specified by:

onChildAdded in interface ComponentCtrl

Overrides:

onChildAdded in class AbstractComponent

See Also:

ComponentCtrl.onChildAdded(org.zkoss.zk.ui.Component)

onChildRemoved

public void onChildRemoved(Component child)

Description copied from class: AbstractComponent

Default: does nothing.

Specified by:

onChildRemoved in interface ComponentCtrl

Overrides:

onChildRemoved in class AbstractComponent

See Also:

ComponentCtrl.onChildRemoved(org.zkoss.zk.ui.Component)

clone

public java.lang.Object clone()

Description copied from interface: Component

Clones the component. All of its children and descendants are cloned. Also, ID are preserved.

Specified by:

clone in interface Component

Overrides:

clone in class Textbox

Returns:

the new component. Notice that it doesn't belong to any page, nor desktop. It doesn't have a parent, either.

sessionWillPassivate

public void sessionWillPassivate(Page page)

Description copied from interface: ComponentCtrl

Notification that the session, which owns this component, is about to be passivated (a.k.a., serialized).

Note: only root components are notified by this method.

Specified by:

sessionWillPassivate in interface ComponentCtrl

Overrides:

sessionWillPassivate in class AbstractComponent

sessionDidActivate

public void sessionDidActivate(Page page)

Description copied from interface: ComponentCtrl

Notification that the session, which owns this component, has just been activated (a.k.a., deserialized).

Note: only root components are notified by this method.

Specified by:

sessionDidActivate in interface ComponentCtrl

Overrides:

sessionDidActivate in class AbstractComponent