Wt  4.0.2
Public Member Functions | List of all members
Wt::WButtonGroup Class Reference

A class for grouping radio buttons logically together. More...

#include <Wt/WButtonGroup.h>

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

Public Member Functions

 WButtonGroup ()
 Creates a new empty button group. More...
 
void addButton (WRadioButton *button, int id=-1)
 Adds a radio button to the group. More...
 
void removeButton (WRadioButton *button)
 Removes a radio button from the group. More...
 
WRadioButtonbutton (int id) const
 Returns the button for the given id. More...
 
int id (WRadioButton *button) const
 Returns the id for the given button. More...
 
virtual const std::string id () const override
 Returns the (unique) identifier for this object. More...
 
std::vector< WRadioButton * > buttons () const
 Returns the buttons in this group.
 
int count () const
 Returns the number of radiobuttons in this group.
 
int checkedId () const
 Returns the id of the checked button. More...
 
void setCheckedButton (WRadioButton *button)
 Sets the currently checked radiobutton. More...
 
WRadioButtoncheckedButton () const
 Returns the checked radiobutton. More...
 
void setSelectedButtonIndex (int idx)
 Sets the currently checked radiobutton. More...
 
int selectedButtonIndex () const
 Returns the index of the checked radiobutton. More...
 
Signal< WRadioButton * > & checkedChanged ()
 Signal emitted when a button was checked. More...
 
- Public Member Functions inherited from Wt::WObject
void addChild (std::unique_ptr< WObject > child)
 Add a child WObject whose lifetime is determined by this WObject.
 
template<typename Child >
Child * addChild (std::unique_ptr< Child > child)
 Add a child WObject, returning a raw pointer. More...
 
std::unique_ptr< WObjectremoveChild (WObject *child)
 Remove a child WObject, so its lifetime is no longer determined by this WObject.
 
virtual void setObjectName (const std::string &name)
 Sets an object name. 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...
 
- Public Member Functions inherited from Wt::Core::observable
 observable () noexcept
 Default constructor.
 
virtual ~observable ()
 Destructor. More...
 

Additional Inherited Members

- Public Types inherited from Wt::WObject
typedef void(WObject::* Method) ()
 Typedef for a WObject method without arguments.
 
- Protected Member Functions inherited from Wt::WObject
virtual WStatelessSlot * getStateless (Method method)
 On-demand stateless slot implementation. More...
 

Detailed Description

A class for grouping radio buttons logically together.

A button group manages a set of radio buttons, making them exclusive of each other.

It is not a widget, but instead provides only a logical grouping. Radio buttons are aware of the group in which they have been added, see WRadioButton::group(). When a button is deleted, it is automatically removed its button group.

It allows you to associate id's with each button, which you may use to identify a particular button. The special value of -1 is reserved to indicate no button.

Usage example:

enum class Vote { Republican = 1, Democrat = 2, NoVote = 10 };
// use a group box as widget container for 3 radio buttons, with a title
auto container = std::make_unique<Wt::WGroupBox>("USA elections vote");
// use a button group to logically group the 3 options
auto group = std::make_shared<Wt::WButtonGroup>();
button = container->addWidget(
std::make_unique<Wt::WRadioButton>(
"I voted Republican"));
container->addWidget(std::make_unique<Wt::WBreak>());
group->addButton(button, Vote::Republican);
button = container->addWidget(
std::make_unique<Wt::WRadioButton>(
"I voted Democrat"));
container->addWidget(std::make_unique<Wt::WBreak>());
group->addButton(button, Vote::Democrat);
button = container->addWidget(
std::make_unique<Wt::WRadioButton>(
"I didn't vote"));
container->addWidget(std::make_unique<Wt::WBreak>());
group->addButton(button, Vote::NoVote);
group->setCheckedButton(group->button(Vote::NoVote));
See also
WRadioButton

Constructor & Destructor Documentation

Wt::WButtonGroup::WButtonGroup ( )

Creates a new empty button group.

Note
The WRadioButtons associated with this WButtonGroup keep a shared_ptr to this WButtonGroup. Therefore, you should store a WButtonGroup in a shared_ptr (e.g. construct it with make_shared) before adding any radio buttons to it.

Member Function Documentation

void Wt::WButtonGroup::addButton ( WRadioButton button,
int  id = -1 
)

Adds a radio button to the group.

You can assign an id to the button. If id is -1, then a unique id will be generated.

Note
WButtonGroup should be owned by a shared_ptr before addButton is called on it!
See also
removeButton(WRadioButton *)
WRadioButton * Wt::WButtonGroup::button ( int  id) const

Returns the button for the given id.

See also
id(), addButton()
WRadioButton * Wt::WButtonGroup::checkedButton ( ) const

Returns the checked radiobutton.

If there is no radiobutton currently checked this function returns 0.

See also
setCheckedButton(), selectedButtonIndex()
Signal< WRadioButton * > & Wt::WButtonGroup::checkedChanged ( )

Signal emitted when a button was checked.

The argument passed is the new checkedButton().

int Wt::WButtonGroup::checkedId ( ) const

Returns the id of the checked button.

Returns the id of the currently checked button, or -1 if no button is currently checked.

int Wt::WButtonGroup::id ( WRadioButton button) const

Returns the id for the given button.

See also
button(), addButton()
virtual const std::string Wt::WButtonGroup::id ( ) const
overridevirtual

Returns the (unique) identifier for this object.

For a WWidget, this corresponds to the id of the DOM element that represents the widget. This is not entirely unique, since a composite widget shares the same id as its implementation.

By default, the id is auto-generated, unless a custom id is set for a widget using WWidget::setId().

See also
WWidget::jsRef()

Reimplemented from Wt::WObject.

void Wt::WButtonGroup::removeButton ( WRadioButton button)

Removes a radio button from the group.

See also
addButton(WRadioButton *, int)
int Wt::WButtonGroup::selectedButtonIndex ( ) const

Returns the index of the checked radiobutton.

The index reflects the order in which the buttons have been added to the button group. Use checkedId() if you want to know the id of the button that is currently checked. If there is no radiobutton selected this function returns -1.

See also
checkedId()
void Wt::WButtonGroup::setCheckedButton ( WRadioButton button)

Sets the currently checked radiobutton.

The button button of this group is checked. A value of 0 will uncheck all radiobuttons.

Initially, no button is checked.

See also
checkedId()
void Wt::WButtonGroup::setSelectedButtonIndex ( int  idx)

Sets the currently checked radiobutton.

Sets the idx'th radiobutton checked. A value of -1 will uncheck all radiobuttons.

Initially, no button is checked.


Generated on Fri Nov 24 2017 for the C++ Web Toolkit (Wt) by doxygen 1.8.11