Package eu.webtoolkit.jwt

Class WComboBox

java.lang.Object

eu.webtoolkit.jwt.WObject

eu.webtoolkit.jwt.WWidget

eu.webtoolkit.jwt.WWebWidget

eu.webtoolkit.jwt.WInteractWidget

eu.webtoolkit.jwt.WFormWidget

eu.webtoolkit.jwt.WComboBox

Direct Known Subclasses:

WSelectionBox

public class WComboBox
extends WFormWidget

A widget that provides a drop-down combo-box control.

A combo box provides the user with a set of options, from which one option may be selected.

WComboBox is an MVC view class, using a simple string list model by default. The model may be populated using addItem() or insertItem() and the contents can be cleared through clear(). These methods manipulate the underlying getModel().

To use the combo box with a custom model instead of the default WStringListModel, use setModel().

To react to selection events, connect to the WFormWidget.changed(), activated() or sactivated() signals.

At all times, the current selection index is available through getCurrentIndex() and the current selection text using getCurrentText().

WComboBox does not have support for auto-completion, this behaviour can be found in the WSuggestionPopup.

WComboBox is an inline widget.

CSS

The widget corresponds to the HTML <select> tag and does not provide styling. It can be styled using inline or external CSS as appropriate.

Nested Class Summary

Nested classes/interfaces inherited from class eu.webtoolkit.jwt.WObject

WObject.FormData

Field Summary

Fields inherited from class eu.webtoolkit.jwt.WInteractWidget

dragTouchEndSlot_, dragTouchSlot_, noDefault

Constructor Summary

Constructors

Constructor	Description
WComboBox()	Creates an empty combo-box..
WComboBox(WContainerWidget parentContainer)	Creates an empty combo-box..

Method Summary

Modifier and Type	Method	Description
Signal1<Integer>	activated()	Signal emitted when the selection changed.
void	addItem(CharSequence text)	Adds an option item.
void	clear()	Clears all items.
int	findText(CharSequence text, MatchOptions flags)	Returns the index of the first item that matches a text.
int	getCount()	Returns the number of items.
int	getCurrentIndex()	Returns the currently selected item.
WString	getCurrentText()	Returns the text of the currently selected item.
WString	getItemText(int index)	Returns the text of a particular item.
WAbstractItemModel	getModel()	Returns the data model.
SelectionMode	getSelectionMode()	Returns the selection mode.
String	getValueText()	Returns the current value.
void	insertItem(int index, CharSequence text)	Inserts an item at the specified position.
boolean	isNoSelectionEnabled()	Returns whether 'no selection' is a valid state.
void	refresh()	Refresh the widget.
void	removeItem(int index)	Removes the item at the specified position.
Signal1<WString>	sactivated()	Signal emitted when the selection changed.
void	setCurrentIndex(int index)	Changes the current selection.
protected void	setFormData(WObject.FormData formData)
void	setItemText(int index, CharSequence text)	Changes the text for a specified option.
void	setModel(WAbstractItemModel model)	Sets the model to be used for the items.
void	setModelColumn(int index)	Sets the column in the model to be used for the items.
void	setNoSelectionEnabled(boolean enabled)	Enables the ability to have 'no currently selected' item.
void	setValueText(String value)	Sets the current value.

Methods inherited from class eu.webtoolkit.jwt.WFormWidget

changed, enableAjax, getLabel, getPlaceholderText, getRealValidator, getTabIndex, getValidator, hasValidatorChanged, isCanReceiveFocus, isReadOnly, propagateSetEnabled, remove, render, setEnabled, setHidden, setPlaceholderText, setReadOnly, setToolTip, setValidator, validate, validated, validatorChanged

Methods inherited from class eu.webtoolkit.jwt.WInteractWidget

clicked, doubleClicked, enterPressed, escapePressed, gestureChanged, gestureEnded, gestureStarted, getMouseOverDelay, isEnabled, keyPressed, keyWentDown, keyWentUp, load, mouseDragged, mouseMoved, mouseWentDown, mouseWentOut, mouseWentOver, mouseWentUp, mouseWheel, setDraggable, setDraggable, setDraggable, setDraggable, setMouseOverDelay, setPopup, touchEnded, touchMoved, touchStarted, unsetDraggable

Methods inherited from class eu.webtoolkit.jwt.WWebWidget

addStyleClass, beingDeleted, blurred, callJavaScriptMember, childrenChanged, createDomElement, doJavaScript, escapeText, escapeText, escapeText, escapeText, find, findById, focussed, getAttributeValue, getBaseZIndex, getChildren, getClearSides, getDecorationStyle, getDomChanges, getFloatSide, getHeight, getHtmlTagName, getId, getJavaScriptMember, getLineHeight, getMargin, getMaximumHeight, getMaximumWidth, getMinimumHeight, getMinimumWidth, getOffset, getPositionScheme, getScrollVisibilityMargin, getStyleClass, getToolTip, getVerticalAlignment, getVerticalAlignmentLength, getWidth, hasFocus, hasStyleClass, hideToolTip, isDisabled, isHidden, isHiddenKeepsGeometry, isInline, isLoaded, isPopup, isRendered, isScrollVisibilityEnabled, isScrollVisible, isSetFirstFocus, isThemeStyleEnabled, isVisible, iterateChildren, jsStringLiteral, jsStringLiteral, manageWidget, parentResized, parentResized, propagateSetVisible, removeScript, removeStyleClass, resize, scrollVisibilityChanged, setAttributeValue, setBaseZIndex, setCanReceiveFocus, setClearSides, setDecorationStyle, setDeferredToolTip, setDisabled, setFlexBox, setFloatSide, setFocus, setHiddenKeepsGeometry, setHtmlTagName, setId, setInline, setJavaScriptMember, setLineHeight, setLoadLaterWhenInvisible, setMargin, setMaximumSize, setMinimumSize, setObjectName, setOffsets, setParentWidget, setPositionScheme, setScrollVisibilityEnabled, setScrollVisibilityMargin, setSelectable, setStyleClass, setTabIndex, setThemeStyleEnabled, setVerticalAlignment, showToolTip, showToolTipOnHover, unescapeText, updateSignalConnection, voidEventSignal, widgetAdded, widgetRemoved

Methods inherited from class eu.webtoolkit.jwt.WWidget

acceptDrops, acceptDrops, addCssRule, addCssRule, addJSignal, addStyleClass, animateHide, animateShow, applyThemeStyles, boxBorder, boxPadding, createJavaScript, disable, dropEvent, enable, getDropTouch, getJsRef, getParent, hide, htmlText, isExposed, isGlobalWidget, isLayoutSizeAware, layoutSizeChanged, needsRerender, positionAt, positionAt, positionAt, positionAt, removeFromParent, removeStyleClass, removeWidget, render, resize, scheduleRender, scheduleRender, scheduleRender, scheduleThemeStyleApply, setClearSides, setDeferredToolTip, setFocus, setHeight, setHidden, setLayoutSizeAware, setMargin, setMargin, setMargin, setMargin, setMargin, setOffsets, setOffsets, setOffsets, setOffsets, setOffsets, setToolTip, setVerticalAlignment, setWidth, show, stopAcceptDrops, toggleStyleClass, toggleStyleClass, tr

Methods inherited from class eu.webtoolkit.jwt.WObject

getObjectName

Methods inherited from class java.lang.Object

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

Constructor Details

WComboBox

public WComboBox(WContainerWidget parentContainer)

Creates an empty combo-box..

WComboBox

public WComboBox()

Creates an empty combo-box..

Calls this((WContainerWidget)null)

Method Details

addItem

public void addItem(CharSequence text)

Adds an option item.

This adds an item to the underlying model. This requires that the getModel() is editable.

Equivalent to insertItem() (getCount(), text).

getCount

public int getCount()

Returns the number of items.

getCurrentIndex

public int getCurrentIndex()

Returns the currently selected item.

If no item is currently selected, the method returns -1.

See Also:

• setNoSelectionEnabled(boolean enabled)

insertItem

public void insertItem(int index,
 CharSequence text)

Inserts an item at the specified position.

The item is inserted in the underlying model at position index. This requires that the getModel() is editable.

See Also:

• addItem(CharSequence text)
• removeItem(int index)

removeItem

public void removeItem(int index)

Removes the item at the specified position.

The item is removed from the underlying model. This requires that the getModel() is editable.

See Also:

• insertItem(int index, CharSequence text)
• clear()

setCurrentIndex

public void setCurrentIndex(int index)

Changes the current selection.

Specify a value of -1 for index to clear the selection.

Note: Setting a value of -1 works only if JavaScript is available.

setItemText

public void setItemText(int index,
 CharSequence text)

Changes the text for a specified option.

The text for the item at position index is changed. This requires that the getModel() is editable.

getCurrentText

public WString getCurrentText()

Returns the text of the currently selected item.

See Also:

• getCurrentIndex()
• getItemText(int index)

getItemText

public WString getItemText(int index)

Returns the text of a particular item.

See Also:

• setItemText(int index, CharSequence text)
• getCurrentText()

setModel

public void setModel(WAbstractItemModel model)

Sets the model to be used for the items.

The default model is a WStringListModel.

Items in the model can be grouped by setting the ItemDataRole.Level. The contents is interpreted by Wt::asString, and subsequent items of the same group are rendered as children of a HTML <optgroup> element.

See Also:

• setModelColumn(int index)

setModelColumn

public void setModelColumn(int index)

Sets the column in the model to be used for the items.

The column index in the model will be used to retrieve data.

The default value is 0.

See Also:

• setModel(WAbstractItemModel model)

getModel

public WAbstractItemModel getModel()

Returns the data model.

See Also:

• setModel(WAbstractItemModel model)

findText

public int findText(CharSequence text,
 MatchOptions flags)

Returns the index of the first item that matches a text.

getSelectionMode

public SelectionMode getSelectionMode()

Returns the selection mode.

Always returns SelectionMode.Single for a combo box, but may return SelectionMode.Extended for a selection box

See Also:

• WSelectionBox.setSelectionMode(SelectionMode mode)

getValueText

public String getValueText()

Returns the current value.

Returns getCurrentText() as a String.

Specified by:

getValueText in class WFormWidget

setValueText

public void setValueText(String value)

Sets the current value.

Sets the current index to the item corresponding to value.

Specified by:

setValueText in class WFormWidget

refresh

public void refresh()

Description copied from class: WWidget

Refresh the widget.

The refresh method is invoked when the locale is changed using WApplication#setLocale() or when the user hit the refresh button.

The widget must actualize its contents in response.

Note: This does not rerender the widget! Calling refresh() usually does not have any effect (unless you've reimplemented refresh() to attach to it an effect).

Overrides:

refresh in class WFormWidget

clear

public void clear()

Clears all items.

Removes all items from the underlying model. This requires that the getModel() is editable.

activated

public Signal1<Integer> activated()

Signal emitted when the selection changed.

The newly selected item is passed as an argument.

See Also:

• sactivated()
• getCurrentIndex()

sactivated

public Signal1<WString> sactivated()

Signal emitted when the selection changed.

The newly selected text is passed as an argument.

See Also:

• activated()
• getCurrentText()

setNoSelectionEnabled

public void setNoSelectionEnabled(boolean enabled)

Enables the ability to have 'no currently selected' item.

The setting may only be changed for a combo box (and not for a selection box). When enabled, the getCurrentIndex() may be '-1' also when the combo box contains values. The user can however not select this option, it is thus only useful as a default value.

By default, no selection is false for a combo-box and true for a selection box.

isNoSelectionEnabled

public boolean isNoSelectionEnabled()

Returns whether 'no selection' is a valid state.

See Also:

• setNoSelectionEnabled(boolean enabled)

setFormData

protected void setFormData(WObject.FormData formData)

Overrides:

setFormData in class WObject