Wt  3.7.1
Public Member Functions | Protected Member Functions | List of all members
Wt::WLabel Class Reference

A label for a form field. More...

#include <Wt/WLabel>

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

Public Member Functions

 WLabel (WContainerWidget *parent=0)
 Creates a label with empty text and optional parent.
 
 WLabel (const WString &text, WContainerWidget *parent=0)
 Creates a label with a given text.
 
 WLabel (WImage *image, WContainerWidget *parent=0)
 Creates a label with an image.
 
WFormWidgetbuddy () const
 Returns the buddy of this label. More...
 
void setBuddy (WFormWidget *buddy)
 Sets the buddy of this label. More...
 
void setBuddy (Ext::FormField *buddy)
 Sets the buddy of this label. More...
 
void setText (const WString &text)
 Sets the label text.
 
const WStringtext () const
 Returns the label text.
 
bool setTextFormat (TextFormat format)
 Sets the text format. More...
 
TextFormat textFormat () const
 Returns the text format. More...
 
void setImage (WImage *image, Side side=Left)
 Sets the image.
 
WImageimage () const
 Returns the image.
 
void setWordWrap (bool wordWrap)
 Configures word wrapping. More...
 
bool wordWrap () const
 Returns whether word wrapping is on. 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 void setHidden (bool hidden, const WAnimation &animation=WAnimation())
 Hides or shows the widget. 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 setToolTip (const WString &text, TextFormat textFormat=PlainText)
 Sets a tooltip. More...
 
virtual void setDeferredToolTip (bool enable, TextFormat textFormat=PlainText)
 Enable deferred tooltip. More...
 
virtual WString toolTip () const
 Returns the tooltip.
 
virtual void refresh ()
 Refresh the widget. More...
 
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 canReceiveFocus () const
 Returns 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...
 
virtual int tabIndex () const
 Returns 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(final override)
 Returns whether scroll visibility detection is enabled for this widget. More...
 
virtual void setScrollVisibilityEnabled (bool enabled) WT_CXX11ONLY(final override)
 Sets whether scroll visibility detection is enabled for this widget. More...
 
virtual int scrollVisibilityMargin () const WT_CXX11ONLY(final override)
 Returns the margin around the viewport within which the widget is considered visible. More...
 
virtual void setScrollVisibilityMargin (int margin) WT_CXX11ONLY(final override)
 Sets the margin around the viewport within which the widget is considered visible. More...
 
virtual Signal< bool > & scrollVisibilityChanged () WT_CXX11ONLY(final override)
 Signal triggered when the scroll visibility of this widget changes. More...
 
virtual bool isScrollVisible () const WT_CXX11ONLY(final override)
 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.
 

Protected Member Functions

virtual void propagateSetEnabled (bool enabled)
 Propagates that a widget was enabled or disabled through children. More...
 
- Protected Member Functions inherited from Wt::WWebWidget
virtual void enableAjax ()
 Progresses to an Ajax-enabled widget. More...
 
virtual WStatelessSlot * getStateless (Method method)
 On-demand stateless slot implementation. More...
 
virtual void render (WFlags< RenderFlag > flags)
 Renders the widget. 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...
 

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...
 
- Static Protected Member Functions inherited from Wt::WObject
static WObjectsender ()
 Returns the sender of the current slot call. More...
 

Detailed Description

A label for a form field.

The label may contain an image and/or text. It acts like a proxy for giving focus to a WFormWidget. When both an image and text are specified, the image is put to the left of the text.

Usage example:

Wt::WLabel *label = new Wt::WLabel("Favourite Actress: ", w);
Wt::WLineEdit *edit = new Wt::WLineEdit("Renee Zellweger", w);
label->setBuddy(edit);

The widget corresponds to the HTML <label> tag. When no buddy is set, it is rendered using an HTML <span> or <div> to avoid click event handling misbehavior on Microsoft Internet Explorer.

WLabel is an inline widget.

CSS

This widget does not provide styling, and can be styled using inline or external CSS as appropriate. A label's text may be styled via a nested <span> element, and it's image may be styled via a nested <img> element.

Member Function Documentation

◆ buddy()

WFormWidget* Wt::WLabel::buddy ( ) const

Returns the buddy of this label.

See also
setBuddy(WFormWidget *)

◆ propagateSetEnabled()

void Wt::WLabel::propagateSetEnabled ( bool  enabled)
protectedvirtual

Propagates that a widget was enabled or disabled through children.

When enabling or disabling a widget, you usually also want to disable contained children. This method is called by setDisabled() to propagate its state to all children.

You may want to reimplement this method if they wish to render differently when a widget is disabled. The default implementation will propagate the signal to all children.

Reimplemented from Wt::WInteractWidget.

◆ setBuddy() [1/2]

void Wt::WLabel::setBuddy ( WFormWidget buddy)

Sets the buddy of this label.

Sets the buddy FormWidget for which this label acts as a proxy.

See also
WFormWidget::label(), setBuddy(Ext::FormField *), buddy()

◆ setBuddy() [2/2]

void Wt::WLabel::setBuddy ( Ext::FormField buddy)

Sets the buddy of this label.

Sets the buddy Ext::FormField for which this label acts as a proxy. When using this method, the result of buddy() is not defined.

See also
Ext::FormField::label(), setBuddy(WFormWidget *)

◆ setTextFormat()

bool Wt::WLabel::setTextFormat ( TextFormat  format)

Sets the text format.

The textFormat controls how the string should be interpreted: either as plain text, which is displayed literally, or as XHTML-markup.

When changing the textFormat to Wt::XHTMLText, and the current text is literal (not created using WString::tr()), the current text is parsed using an XML parser which discards malicious tags and attributes silently. When the parser encounters an XML parse error, the textFormat is left unchanged, and this method returns false.

Returns whether the textFormat could be set for the current text.

The default format is Wt::XHTMLText.

◆ setWordWrap()

void Wt::WLabel::setWordWrap ( bool  wordWrap)

Configures word wrapping.

When wordWrap is true, the widget may break lines, creating a multi-line text. When wordWrap is false, the text will displayed on a single line, unless the text contains end-of-lines (for Wt::PlainText) or <br /> tags or other block-level tags (for Wt::XHTMLText).

The default value is false.

See also
wordWrap()

◆ textFormat()

TextFormat Wt::WLabel::textFormat ( ) const

Returns the text format.

See also
setTextFormat()

◆ wordWrap()

bool Wt::WLabel::wordWrap ( ) const

Returns whether word wrapping is on.

See also
setWordWrap()

Generated on Tue Dec 15 2020 for the C++ Web Toolkit (Wt) by doxygen 1.8.13