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# QButtonGroup Class Reference
[QtGui module]

The QButtonGroup class provides a container to organize groups of button widgets. More...

Inherits QObject.

### Methods

- __init__ (self, QObject parent = None)
- addButton (self, QAbstractButton)
- addButton (self, QAbstractButton, int)
- QAbstractButton button (self, int)
- list-of-QAbstractButton buttons (self)
- QAbstractButton checkedButton (self)
- int checkedId (self)
- bool exclusive (self)
- int id (self, QAbstractButton)
- removeButton (self, QAbstractButton)
- setExclusive (self, bool)
- setId (self, QAbstractButton, int)

### Qt Signals

- void buttonClicked (QAbstractButton *)
- void buttonClicked (int)
- void buttonPressed (QAbstractButton *)
- void buttonPressed (int)
- void buttonReleased (QAbstractButton *)
- void buttonReleased (int)

## Detailed Description

The QButtonGroup class provides a container to organize groups of button widgets.

QButtonGroup provides an abstract container into which button widgets can be placed. It does not provide a visual representation of this container (see QGroupBox for a container widget), but instead manages the states of each of the buttons in the group.

An exclusive button group switches off all checkable (toggle) buttons except the one that was clicked. By default, a button group is exclusive. The buttons in a button group are usually checkable QPushButton's, QCheckBoxes (normally for non-exclusive button groups), or QRadioButtons. If you create an exclusive button group, you should ensure that one of the buttons in the group is initially checked; otherwise, the group will initially be in a state where no buttons are checked.

A button is added to the group with addButton(). It can be removed from the group with removeButton(). If the group is exclusive, the currently checked button is available as checkedButton(). If a button is clicked the buttonClicked() signal is emitted. For a checkable button in an exclusive group this means that the button was checked. The list of buttons in the group is returned by buttons().

In addition, QButtonGroup can map between integers and buttons. You can assign an integer id to a button with setId(), and retrieve it with id(). The id of the currently checked button is available with checkedId(), and there is an overloaded signal buttonClicked() which emits the id of the button. The id `-1` is reserved by QButtonGroup to mean "no such button". The purpose of the mapping mechanism is to simplify the representation of enum values in a user interface.

See also QGroupBox, QPushButton, QCheckBox, and QRadioButton.

## Method Documentation

### QButtonGroup.__init__ (self, QObject parent = None)

The parent argument, if not None, causes self to be owned by Qt instead of PyQt.

Constructs a new, empty button group with the given parent.

See also addButton() and setExclusive().

### QButtonGroup.addButton (self, QAbstractButton)

Adds the given button to the end of the group's internal list of buttons. An id will be assigned to the button by this QButtonGroup. Automatically assigned ids are guaranteed to be negative, starting with -2. If you are also assigning your own ids, use positive values to avoid conflicts.

See also removeButton() and buttons().

### QButtonGroup.addButton (self, QAbstractButton, int)

Adds the given button to the button group, with the given id. It is recommended to assign only positive ids.

See also removeButton() and buttons().

### QAbstractButton QButtonGroup.button (self, int)

Returns the button with the specified id, or 0 if no such button exists.

This function was introduced in Qt 4.1.

### list-of-QAbstractButton QButtonGroup.buttons (self)

Returns the list of this groups's buttons. This may be empty.

See also addButton() and removeButton().

### QAbstractButton QButtonGroup.checkedButton (self)

Returns the button group's checked button, or 0 if no buttons are checked.

See also buttonClicked().

### int QButtonGroup.checkedId (self)

Returns the id of the checkedButton(), or -1 if no button is checked.

This function was introduced in Qt 4.1.

See also setId().

### bool QButtonGroup.exclusive (self)

### int QButtonGroup.id (self, QAbstractButton)

Returns the id for the specified button, or -1 if no such button exists.

This function was introduced in Qt 4.1.

See also setId().

### QButtonGroup.removeButton (self, QAbstractButton)

Removes the given button from the button group.

See also addButton() and buttons().

### QButtonGroup.setExclusive (self, bool)

### QButtonGroup.setId (self, QAbstractButton, int)

Sets the id for the specified button. Note that id can not be -1.

This function was introduced in Qt 4.1.

See also id().

## Qt Signal Documentation

### void buttonClicked (QAbstractButton *)

This is the default overload of this signal.

This signal is emitted when the given button is clicked. A button is clicked when it is first pressed and then released, when its shortcut key is typed, or programmatically when QAbstractButton.click() or QAbstractButton.animateClick() is called.

See also checkedButton() and QAbstractButton.clicked().

### void buttonClicked (int)

This signal is emitted when a button with the given id is clicked.

See also checkedButton() and QAbstractButton.clicked().

### void buttonPressed (QAbstractButton *)

This is the default overload of this signal.

This signal is emitted when the given button is pressed down.

This function was introduced in Qt 4.2.

See also QAbstractButton.pressed().

### void buttonPressed (int)

This signal is emitted when a button with the given id is pressed down.

This function was introduced in Qt 4.2.

See also QAbstractButton.pressed().

### void buttonReleased (QAbstractButton *)

This is the default overload of this signal.

This signal is emitted when the given button is released.

This function was introduced in Qt 4.2.

See also QAbstractButton.released().

### void buttonReleased (int)

This signal is emitted when a button with the given id is released.

This function was introduced in Qt 4.2.

See also QAbstractButton.released().