Wt  3.3.9
Public Member Functions | List of all members
Wt::WComboBox Class Reference

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

#include <Wt/WComboBox>

Inheritance diagram for Wt::WComboBox:
Inheritance graph
[legend]

Public Member Functions

 WComboBox (WContainerWidget *parent=0)
 Creates an empty combo-box with optional parent.
 
void addItem (const WString &text)
 Adds an option item. More...
 
int count () const
 Returns the number of items.
 
int currentIndex () const
 Returns the currently selected item. More...
 
void insertItem (int index, const WString &text)
 Inserts an item at the specified position. More...
 
void removeItem (int index)
 Removes the item at the specified position. More...
 
void setCurrentIndex (int index)
 Changes the current selection. More...
 
void setItemText (int index, const WString &text)
 Changes the text for a specified option. More...
 
const WString currentText () const
 Returns the text of the currently selected item. More...
 
const WString itemText (int index) const
 Returns the text of a particular item. More...
 
void setModel (WAbstractItemModel *model)
 Sets the model to be used for the items. More...
 
void setModelColumn (int index)
 Sets the column in the model to be used for the items. More...
 
WAbstractItemModelmodel () const
 Returns the data model. More...
 
int findText (const WString &text, WFlags< MatchFlag > flags=MatchExactly|MatchCaseSensitive)
 Returns the index of the first item that matches a text.
 
virtual SelectionMode selectionMode () const
 Returns the selection mode. More...
 
virtual WString valueText () const
 Returns the current value. More...
 
virtual void setValueText (const WString &value)
 Sets the current value. More...
 
virtual void refresh ()
 Refresh the widget. More...
 
void clear ()
 Clears all items. More...
 
Signal< int > & activated ()
 Signal emitted when the selection changed. More...
 
Signal< WString > & sactivated ()
 Signal emitted when the selection changed. More...
 
void setNoSelectionEnabled (bool enabled)
 Enables the ability to have 'no currently selected' item. More...
 
bool noSelectionEnabled () const
 Returns whether 'no selection' is a valid state. More...
 
- Public Member Functions inherited from Wt::WFormWidget
 WFormWidget (WContainerWidget *parent=0)
 Creates a WFormWidget with an optional parent.
 
 ~WFormWidget ()
 Destructor. More...
 
WLabellabel () const
 Returns the label associated with this widget. More...
 
virtual void setHidden (bool hidden, const WAnimation &animation=WAnimation())
 Sets the hidden state of this widget. More...
 
void setValidator (WValidator *validator)
 Sets a validator for this field. More...
 
virtual WValidatorvalidator () const
 Returns the validator.
 
virtual WValidator::State validate ()
 Validates the field. More...
 
void setEnabled (bool enabled)
 Sets whether the widget is enabled. More...
 
virtual void setReadOnly (bool readOnly)
 Sets the element read-only. More...
 
bool isReadOnly () const
 Returns whether the form element is read-only. More...
 
void setEmptyText (const WString &emptyText)
 Sets the placeholder text (deprecated). More...
 
const WStringemptyText () const
 Returns the placeholder text (deprecated). More...
 
virtual void setPlaceholderText (const WString &placeholder)
 Sets the placeholder text. More...
 
const WStringplaceholderText () const
 Returns the placeholder text. More...
 
EventSignalchanged ()
 Signal emitted when the value was changed. More...
 
EventSignalselected ()
 Signal emitted when ??
 
Signal< WValidator::Result > & validated ()
 Signal emitted when the widget is being validated. More...
 
virtual void setToolTip (const WString &text, TextFormat textFormat=PlainText)
 Sets a tooltip. More...
 
virtual bool canReceiveFocus () const
 Returns whether the widget can receive focus. More...
 
virtual int tabIndex () const
 Returns the tab index. More...
 
- Public Member Functions inherited from Wt::WInteractWidget
 WInteractWidget (WContainerWidget *parent=0)
 Create an InteractWidget with optional parent.
 
EventSignal< WKeyEvent > & keyWentDown ()
 Event signal emitted when a keyboard key is pushed down. More...
 
EventSignal< WKeyEvent > & keyPressed ()
 Event signal emitted when a "character" was entered. More...
 
EventSignal< WKeyEvent > & keyWentUp ()
 Event signal emitted when a keyboard key is released. More...
 
EventSignalenterPressed ()
 Event signal emitted when enter was pressed. More...
 
EventSignalescapePressed ()
 Event signal emitted when escape was pressed. More...
 
EventSignal< WMouseEvent > & clicked ()
 Event signal emitted when a mouse key was clicked on this widget. More...
 
EventSignal< WMouseEvent > & doubleClicked ()
 Event signal emitted when a mouse key was double clicked on this widget. More...
 
EventSignal< WMouseEvent > & mouseWentDown ()
 Event signal emitted when a mouse key was pushed down on this widget. More...
 
EventSignal< WMouseEvent > & mouseWentUp ()
 Event signal emitted when a mouse key was released on this widget. More...
 
EventSignal< WMouseEvent > & mouseWentOut ()
 Event signal emitted when the mouse went out of this widget. More...
 
EventSignal< WMouseEvent > & mouseWentOver ()
 Event signal emitted when the mouse entered this widget. More...
 
EventSignal< WMouseEvent > & mouseMoved ()
 Event signal emitted when the mouse moved over this widget. More...
 
EventSignal< WMouseEvent > & mouseDragged ()
 Event signal emitted when the mouse is dragged over this widget. More...
 
EventSignal< WMouseEvent > & mouseWheel ()
 Event signal emitted when the mouse scroll wheel was used. More...
 
EventSignal< WTouchEvent > & touchStarted ()
 Event signal emitted when a finger is placed on the screen. More...
 
EventSignal< WTouchEvent > & touchEnded ()
 Event signal emitted when a finger is removed from the screen. More...
 
EventSignal< WTouchEvent > & touchMoved ()
 Event signal emitted when a finger, which is already placed on the screen, is moved across the screen. More...
 
EventSignal< WGestureEvent > & gestureStarted ()
 Event signal emitted when a gesture is started. More...
 
EventSignal< WGestureEvent > & gestureChanged ()
 Event signal emitted when a gesture is changed. More...
 
EventSignal< WGestureEvent > & gestureEnded ()
 Event signal emitted when a gesture is ended. More...
 
void setDraggable (const std::string &mimeType, WWidget *dragWidget=0, bool isDragWidgetOnly=false, WObject *sourceWidget=0)
 Configure dragging for drag and drop. More...
 
void unsetDraggable ()
 Disable drag & drop for this widget. More...
 
void setMouseOverDelay (int delay)
 Sets a delay for the mouse over event. More...
 
int mouseOverDelay () const
 Returns the mouse over signal delay. More...
 
virtual void setPopup (bool popup)
 Lets the widget overlay over other sibling widgets. More...
 
virtual void load ()
 Loads content just before the widget is used. More...
 
virtual bool isEnabled () const
 Returns whether the widget is enabled. More...
 
- Public Member Functions inherited from Wt::WWebWidget
 WWebWidget (WContainerWidget *parent=0)
 Construct a WebWidget with a given parent. More...
 
virtual void setPositionScheme (PositionScheme scheme)
 Sets the CSS position scheme. More...
 
virtual PositionScheme positionScheme () const
 Returns the CSS position scheme. More...
 
virtual void setOffsets (const WLength &offset, WFlags< Side > sides=All)
 Sets CSS offsets for a non-statically positioned widget. More...
 
virtual WLength offset (Side s) const
 Returns a CSS offset. More...
 
virtual void resize (const WLength &width, const WLength &height)
 Resizes the widget. More...
 
virtual WLength width () const
 Returns the width. More...
 
virtual WLength height () const
 Returns the height. More...
 
virtual void setMinimumSize (const WLength &width, const WLength &height)
 Sets a minimum size. More...
 
virtual WLength minimumWidth () const
 Returns the minimum width. More...
 
virtual WLength minimumHeight () const
 Returns the minimum height. More...
 
virtual void setMaximumSize (const WLength &width, const WLength &height)
 Sets a maximum size. More...
 
virtual WLength maximumWidth () const
 Returns the maximum width. More...
 
virtual WLength maximumHeight () const
 Returns the maximum height. More...
 
virtual void setLineHeight (const WLength &height)
 Sets the CSS line height for contained text.
 
virtual WLength lineHeight () const
 Returns the CSS line height for contained text. More...
 
virtual void setFloatSide (Side s)
 Specifies a CSS float side. More...
 
virtual Side floatSide () const
 Returns the CSS float side. More...
 
virtual void setClearSides (WFlags< Side > sides)
 Sets the sides that should be cleared of floats. More...
 
virtual WFlags< SideclearSides () const
 Returns the sides that should remain empty. More...
 
virtual void setMargin (const WLength &margin, WFlags< Side > sides=All)
 Sets CSS margins around the widget. More...
 
virtual WLength margin (Side side) const
 Returns a CSS margin set. More...
 
virtual void setHiddenKeepsGeometry (bool enabled)
 Sets whether the widget keeps its geometry when hidden. More...
 
virtual bool hiddenKeepsGeometry () const
 Returns whether the widget keeps its geometry when hidden. More...
 
virtual bool isHidden () const
 Returns whether the widget is set hidden. More...
 
virtual bool isVisible () const
 Returns whether the widget is visible. More...
 
virtual void setDisabled (bool disabled)
 Sets whether the widget is disabled. More...
 
virtual bool isDisabled () const
 Returns whether the widget is set disabled. More...
 
virtual bool isPopup () const
 Returns whether the widget is overlayed. More...
 
virtual void setInline (bool isInline)
 Sets whether the widget is displayed inline or as a block. More...
 
virtual bool isInline () const
 Returns whether the widget is displayed inline or as block. More...
 
virtual void setDecorationStyle (const WCssDecorationStyle &style)
 Sets a CSS decoration style. More...
 
virtual WCssDecorationStyledecorationStyle ()
 Returns the decoration style of this widget. More...
 
virtual void setStyleClass (const WString &styleClass)
 Sets (one or more) CSS style classes. More...
 
virtual WString styleClass () const
 Returns the CSS style class. More...
 
virtual void addStyleClass (const WString &styleClass, bool force=false)
 Adds a CSS style class. More...
 
virtual void removeStyleClass (const WString &styleClass, bool force=false)
 Removes a CSS style class. More...
 
virtual bool hasStyleClass (const WString &styleClass) const
 Returns whether the widget has a style class.
 
virtual void setVerticalAlignment (AlignmentFlag alignment, const WLength &length=WLength())
 Sets the vertical alignment. More...
 
virtual AlignmentFlag verticalAlignment () const
 Returns the vertical alignment. More...
 
virtual WLength verticalAlignmentLength () const
 Returns the fixed vertical alignment that was set. More...
 
virtual void setDeferredToolTip (bool enable, TextFormat textFormat=PlainText)
 Enable deferred tooltip. More...
 
virtual WString toolTip () const
 Returns the tooltip.
 
virtual void setAttributeValue (const std::string &name, const WString &value)
 Sets an attribute value. More...
 
virtual WString attributeValue (const std::string &name) const
 Returns an attribute value. More...
 
virtual void setJavaScriptMember (const std::string &name, const std::string &value)
 Sets a JavaScript member. More...
 
virtual std::string javaScriptMember (const std::string &name) const
 Returns the value of a JavaScript member. More...
 
virtual void callJavaScriptMember (const std::string &name, const std::string &args)
 Calls a JavaScript member. More...
 
virtual bool loaded () const
 Returns whether this widget has been loaded. More...
 
virtual void setId (const std::string &id)
 Sets the CSS Id. More...
 
virtual WWidgetfind (const std::string &name)
 Finds a descendent widget by name. More...
 
virtual WWidgetfindById (const std::string &id)
 Finds a descendent widget by id.
 
virtual void setSelectable (bool selectable)
 Sets as selectable. More...
 
virtual void doJavaScript (const std::string &javascript)
 Executes the given JavaScript statements when the widget is rendered or updated. More...
 
virtual const std::string id () const
 Returns the (unique) identifier for this object. More...
 
void setLoadLaterWhenInvisible (bool)
 Change the way the widget is loaded when invisible. More...
 
std::string htmlTagName () const
 returns the current html tag name More...
 
void setHtmlTagName (const std::string &tag)
 set the custom HTML tag name More...
 
const std::vector< WWidget * > & children () const
 Returns contained widgets. More...
 
SignalchildrenChanged ()
 Signal emitted when children have been added or removed. More...
 
virtual void setCanReceiveFocus (bool enabled)
 Sets whether the widget can receive focus. More...
 
virtual bool setFirstFocus ()
 Set focus on the widget's first descendant. More...
 
virtual void setFocus (bool focus)
 Sets focus. More...
 
virtual bool hasFocus () const
 Returns whether the widget currently has the focus.
 
virtual void setTabIndex (int index)
 Sets the tab index. More...
 
EventSignalblurred ()
 Signal emitted when the widget lost focus. More...
 
EventSignalfocussed ()
 Signal emitted when the widget recieved focus. More...
 
virtual bool scrollVisibilityEnabled () const WT_CXX11ONLY(finaloverride)
 Returns whether scroll visibility detection is enabled for this widget. More...
 
virtual void setScrollVisibilityEnabled (bool enabled) WT_CXX11ONLY(finaloverride)
 Sets whether scroll visibility detection is enabled for this widget. More...
 
virtual int scrollVisibilityMargin () const WT_CXX11ONLY(finaloverride)
 Returns the margin around the viewport within which the widget is considered visible. More...
 
virtual void setScrollVisibilityMargin (int margin) WT_CXX11ONLY(finaloverride)
 Sets the margin around the viewport within which the widget is considered visible. More...
 
virtual Signal< bool > & scrollVisibilityChanged () WT_CXX11ONLY(finaloverride)
 Signal triggered when the scroll visibility of this widget changes. More...
 
virtual bool isScrollVisible () const WT_CXX11ONLY(finaloverride)
 Returns whether this widget is currently considered scroll visible. More...
 
virtual void setThemeStyleEnabled (bool enabled)
 Sets whether theme styling for a widget is enabled or disabled. More...
 
virtual bool isThemeStyleEnabled () const
 Returns whether this widget is currently styled by the chosen theme. More...
 
- Public Member Functions inherited from Wt::WWidget
virtual ~WWidget ()
 Destructor. More...
 
WWidgetparent () const
 Returns the parent widget. More...
 
virtual void removeChild (WObject *child)
 Removes a child object. More...
 
void setWidth (const WLength &width)
 Sets the width. More...
 
void setHeight (const WLength &height)
 Sets the height. More...
 
virtual void positionAt (const WWidget *widget, Orientation orientation=Vertical)
 Positions a widget next to another widget. More...
 
virtual void toggleStyleClass (const WString &styleClass, bool add, bool force=false)
 Toggles a CSS style class.
 
std::string jsRef () const
 Returns a JavaScript expression to the corresponding DOM node. More...
 
void setFocus ()
 Sets focus. More...
 
virtual void acceptDrops (const std::string &mimeType, const WString &hoverStyleClass=WString())
 Sets a mime type to be accepted for dropping. More...
 
virtual void stopAcceptDrops (const std::string &mimeType)
 Indicates that a mime type is no longer accepted for dropping. More...
 
virtual void setObjectName (const std::string &name)
 Sets an object name. More...
 
virtual void htmlText (std::ostream &out)
 Streams the (X)HTML representation. More...
 
bool isRendered () const
 Returns whether the widget is rendered. More...
 
void hide ()
 Hides the widget. More...
 
void animateHide (const WAnimation &animation)
 Hides the widget using an animation. More...
 
void show ()
 Shows the widget. More...
 
void animateShow (const WAnimation &animation)
 Shows the widget using an animation. More...
 
void enable ()
 Enables the widget. More...
 
void disable ()
 Disable thes widget. More...
 
bool layoutSizeAware () const
 Returns whether the widget is layout size aware. More...
 
- Public Member Functions inherited from Wt::WObject
 WObject (WObject *parent=0)
 Create a WObject with a given parent object. More...
 
virtual ~WObject ()
 Destructor. More...
 
virtual std::string objectName () const
 Returns the object name. More...
 
void resetLearnedSlots ()
 Resets learned stateless slot implementations. More...
 
template<class T >
void resetLearnedSlot (void(T::*method)())
 Resets a learned stateless slot implementation. More...
 
template<class T >
WStatelessSlot * implementStateless (void(T::*method)())
 Declares a slot to be stateless and learn client-side behaviour on first invocation. More...
 
template<class T >
WStatelessSlot * implementStateless (void(T::*method)(), void(T::*undoMethod)())
 Declares a slot to be stateless and learn client-side behaviour in advance. More...
 
void isNotStateless ()
 Marks the current function as not stateless. More...
 
template<class T >
WStatelessSlot * implementJavaScript (void(T::*method)(), const std::string &jsCode)
 Provides a JavaScript implementation for a method. More...
 
void addChild (WObject *child)
 Adds a child object. More...
 
const std::vector< WObject * > & children () const
 Returns the children.
 
WObjectparent () const
 Returns the parent object.
 

Additional Inherited Members

- Public Types inherited from Wt::WObject
typedef void(WObject::* Method) ()
 Typedef for a WObject method without arguments.
 
- Static Public Member Functions inherited from Wt::WWebWidget
static WString escapeText (const WString &text, bool newlinesToo=false)
 Escape HTML control characters in the text, to display literally (deprecated). More...
 
static std::string & escapeText (std::string &text, bool newlinestoo=false)
 Escape HTML control characters in the text, to display literally (deprecated). More...
 
static bool removeScript (WString &text)
 Remove tags/attributes from text that are not passive (deprecated). More...
 
static std::string jsStringLiteral (const std::string &v, char delimiter= '\'')
 Turn a UTF8 encoded string into a JavaScript string literal. More...
 
- Static Public Member Functions inherited from Wt::WWidget
static WString tr (const char *key)
 Short hand for WString::tr() More...
 
- Protected Member Functions inherited from Wt::WFormWidget
virtual void enableAjax ()
 Progresses to an Ajax-enabled widget. More...
 
virtual void render (WFlags< RenderFlag > flags)
 Renders the widget. More...
 
virtual void propagateSetEnabled (bool enabled)
 Propagates that a widget was enabled or disabled through children. More...
 
- Protected Member Functions inherited from Wt::WWebWidget
virtual WStatelessSlot * getStateless (Method method)
 On-demand stateless slot implementation. More...
 
- Protected Member Functions inherited from Wt::WWidget
void setLayoutSizeAware (bool sizeAware)
 Sets the widget to be aware of its size set by a layout manager. More...
 
virtual void layoutSizeChanged (int width, int height)
 Virtual method that indicates a size change. More...
 
 WWidget (WContainerWidget *parent=0)
 Creates a widget. More...
 
virtual void dropEvent (WDropEvent dropEvent)
 Handles a drop event. More...
 
virtual int boxPadding (Orientation orientation) const
 Returns the widget's built-in padding. More...
 
virtual int boxBorder (Orientation orientation) const
 Returns the widget's built-in border width. More...
 
void scheduleRender (WFlags< RepaintFlag > flags=0)
 Schedules rerendering of the widget. More...
 
- Static Protected Member Functions inherited from Wt::WObject
static WObjectsender ()
 Returns the sender of the current slot call. More...
 

Detailed Description

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(const WString&) or insertItem(int, const WString&) and the contents can be cleared through clear(). These methods manipulate the underlying model().

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

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

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

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

Usage example:

Wt::WComboBox *combo = new Wt::WComboBox(this);
combo->addItem("Clint Eastwood");
combo->addItem("Mick Jagger");
combo->addItem("Johnny Depp");
combo->addItem("Kate Winslet");
combo->setCurrentIndex(2); // Johnny Depp
combo->activated().connect(this, &MyWidget::comboChanged);

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.

Member Function Documentation

Signal<int>& Wt::WComboBox::activated ( )

Signal emitted when the selection changed.

The newly selected item is passed as an argument.

See also
sactivated(), currentIndex()
void Wt::WComboBox::addItem ( const WString text)

Adds an option item.

Equivalent to insertItem (count(), text).

void Wt::WComboBox::clear ( )

Clears all items.

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

int Wt::WComboBox::currentIndex ( ) const

Returns the currently selected item.

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

By default, for a combo box, the first item is selected, and thus currentIndex() = 0, while for a selection box no item is selected.

const WString Wt::WComboBox::currentText ( ) const

Returns the text of the currently selected item.

See also
currentIndex(), itemText(int) const
void Wt::WComboBox::insertItem ( int  index,
const WString text 
)

Inserts an item at the specified position.

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

See also
addItem(const WString&), removeItem(int)
const WString Wt::WComboBox::itemText ( int  index) const

Returns the text of a particular item.

See also
setItemText(int, const WString&), currentText()
WAbstractItemModel* Wt::WComboBox::model ( ) const

Returns the data model.

See also
setModel()
bool Wt::WComboBox::noSelectionEnabled ( ) const

Returns whether 'no selection' is a valid state.

See also
setNoSelectionEnabled()
void Wt::WComboBox::refresh ( )
virtual

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).

Reimplemented from Wt::WFormWidget.

void Wt::WComboBox::removeItem ( int  index)

Removes the item at the specified position.

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

See also
insertItem(int index, const WString&), clear()
Signal<WString>& Wt::WComboBox::sactivated ( )

Signal emitted when the selection changed.

The newly selected text is passed as an argument.

See also
activated(), currentText()
virtual SelectionMode Wt::WComboBox::selectionMode ( ) const
virtual

Returns the selection mode.

Always returns SingleSelection for a combo box, but may return ExtendedSelection for a selection box

See also
WSelectionBox::setSelectionMode()

Reimplemented in Wt::WSelectionBox.

void Wt::WComboBox::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.
void Wt::WComboBox::setItemText ( int  index,
const WString text 
)

Changes the text for a specified option.

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

void Wt::WComboBox::setModel ( WAbstractItemModel model)

Sets the model to be used for the items.

The model may not be 0, and ownership of the model is not transferred.

The default value is a WStringListModel that is owned by the combo box. Items in the model can be grouped by setting the LevelRole. 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)
void Wt::WComboBox::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()
void Wt::WComboBox::setNoSelectionEnabled ( bool  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 currentIndex() 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.

void Wt::WComboBox::setValueText ( const WString value)
virtual

Sets the current value.

Sets the current index to the item corresponding to value.

Implements Wt::WFormWidget.

WString Wt::WComboBox::valueText ( ) const
virtual

Returns the current value.

Returns currentText() converted from a WString to a string.

Implements Wt::WFormWidget.


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