## GtkRadioButton

GtkRadioButton — A choice from multiple check buttons

## Synopsis

    #include <gtk/gtk.h>

                GtkRadioButton;
    GtkWidget*  gtk_radio_button_new            (GSList *group);
    GtkWidget*  gtk_radio_button_new_from_widget
                                                (GtkRadioButton *group);
    GtkWidget*  gtk_radio_button_new_with_label (GSList *group,
                                                 const gchar *label);
    GtkWidget*  gtk_radio_button_new_with_label_from_widget
                                                (GtkRadioButton *group,
                                                 const gchar *label);
    GtkWidget*  gtk_radio_button_new_with_mnemonic
                                                (GSList *group,
                                                 const gchar *label);
    GtkWidget*  gtk_radio_button_new_with_mnemonic_from_widget
                                                (GtkRadioButton *group,
                                                 const gchar *label);
    #define     gtk_radio_button_group
    void        gtk_radio_button_set_group      (GtkRadioButton *radio_button,
                                                 GSList *group);
    GSList*     gtk_radio_button_get_group      (GtkRadioButton *radio_button);

## Object Hierarchy

      GObject
       +----GtkObject
             +----GtkWidget
                   +----GtkContainer
                         +----GtkBin
                               +----GtkButton
                                     +----GtkToggleButton
                                           +----GtkCheckButton
                                                 +----GtkRadioButton

## Implemented Interfaces

GtkRadioButton implements AtkImplementorIface.

## Properties

      "group"                GtkRadioButton        : Write

## Signal Prototypes

    "group-changed"
                void        user_function      (GtkRadioButton *radiobutton,
                                                gpointer user_data);

## Description

A single radio button performs the same basic function as a GtkCheckButton, as its position in the object hierarchy reflects. It is only when multiple radio buttons are grouped together that they become a different user interface component in their own right.

Every radio button is a member of some group of radio buttons. When one is selected, all other radio buttons in the same group are deselected. A GtkRadioButton is one way of giving the user a choice from many options.

Radio button widgets are created with `gtk_radio_button_new()`, passing NULL as the argument if this is the first radio button in a group. In subsequent calls, the group you wish to add this button to should be passed as an argument. Optionally, `gtk_radio_button_new_with_label()` can be used if you want a text label on the radio button.

Alternatively, when adding widgets to an existing group of radio buttons, use `gtk_radio_button_new_from_widget()` with a GtkRadioButton that already has a group assigned to it. The convenience function `gtk_radio_button_new_with_label_from_widget()` is also provided.

To retrieve the group a GtkRadioButton is assigned to, use `gtk_radio_button_get_group()`.

To remove a GtkRadioButton from one group and make it part of a new one, use `gtk_radio_button_set_group()`.

The group list does not need to be freed, as each GtkRadioButton will remove itself and its list item when it is destroyed.

Example 1. How to create a group of two radio buttons.

    void create_radio_buttons (void) {

       GtkWidget *window, *radio1, *radio2, *box, *entry;
       window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
       box = gtk_vbox_new (TRUE, 2);

       /* Create a radio button with a GtkEntry widget */
       radio1 = gtk_radio_button_new (NULL);
       entry = gtk_entry_new ();
       gtk_container_add (GTK_CONTAINER (radio1), entry);

       /* Create a radio button with a label */
       radio2 = gtk_radio_button_new_with_label_from_widget (GTK_RADIO_BUTTON (radio1),
    							"I'm the second radio button.");

       /* Pack them into a box, then show all the widgets */
       gtk_box_pack_start (GTK_BOX (box), radio1, TRUE, TRUE, 2);
       gtk_box_pack_start (GTK_BOX (box), radio2, TRUE, TRUE, 2);
       gtk_container_add (GTK_CONTAINER (window), box);
       gtk_widget_show_all (window);
       return;
    }

When an unselected button in the group is clicked the clicked button receives the "toggled" signal, as does the previously selected button. Inside the "toggled" handler, `gtk_toggle_button_get_active()` can be used to determine if the button has been selected or deselected.

## Details

### GtkRadioButton

    typedef struct _GtkRadioButton GtkRadioButton;

Contains only private data that should be read and manipulated using the functions below.

### gtk_radio_button_new ()

    GtkWidget*  gtk_radio_button_new            (GSList *group);

Creates a new GtkRadioButton. To be of any practical value, a widget should then be packed into the radio button.

`group` : | an existing radio button group, or `NULL` if you are creating a new group.
Returns : | a new radio button.

### gtk_radio_button_new_from_widget ()

    GtkWidget*  gtk_radio_button_new_from_widget
                                                (GtkRadioButton *group);

Creates a new GtkRadioButton, adding it to the same group as `group`. As with `gtk_radio_button_new()`, a widget should be packed into the radio button.

`group` : | an existing GtkRadioButton.
Returns : | a new radio button.

### gtk_radio_button_new_with_label ()

    GtkWidget*  gtk_radio_button_new_with_label (GSList *group,
                                                 const gchar *label);

Creates a new GtkRadioButton with a text label.

`group` : | an existing radio button group, or `NULL` if you are creating a new group.
`label` : | the text label to display next to the radio button.
Returns : | a new radio button.

### gtk_radio_button_new_with_label_from_widget ()

    GtkWidget*  gtk_radio_button_new_with_label_from_widget
                                                (GtkRadioButton *group,
                                                 const gchar *label);

Creates a new GtkRadioButton with a text label, adding it to the same group as `group`.

`group` : | an existing GtkRadioButton.
`label` : | a text string to display next to the radio button.
Returns : | a new radio button.

### gtk_radio_button_new_with_mnemonic ()

    GtkWidget*  gtk_radio_button_new_with_mnemonic
                                                (GSList *group,
                                                 const gchar *label);

Creates a new GtkRadioButton containing a label, adding it to the same group as `group`. The label will be created using `gtk_label_new_with_mnemonic()`, so underscores in `label` indicate the mnemonic for the button.

`group` : | the radio button group
`label` : | the text of the button, with an underscore in front of the mnemonic character
Returns : | a new GtkRadioButton

### gtk_radio_button_new_with_mnemonic_from_widget ()

    GtkWidget*  gtk_radio_button_new_with_mnemonic_from_widget
                                                (GtkRadioButton *group,
                                                 const gchar *label);

Creates a new GtkRadioButton containing a label. The label will be created using `gtk_label_new_with_mnemonic()`, so underscores in `label` indicate the mnemonic for the button.

`group` : | widget to get radio group from
`label` : | the text of the button, with an underscore in front of the mnemonic character
Returns : | a new GtkRadioButton

### gtk_radio_button_group

    #define gtk_radio_button_group gtk_radio_button_get_group

### Warning

`gtk_radio_button_group` is deprecated and should not be used in newly-written code.

Deprecated compatibility macro. Use `gtk_radio_button_get_group()` instead.

### gtk_radio_button_set_group ()

    void        gtk_radio_button_set_group      (GtkRadioButton *radio_button,
                                                 GSList *group);

Sets a GtkRadioButton's group. It should be noted that this does not change the layout of your interface in any way, so if you are changing the group, it is likely you will need to re-arrange the user interface to reflect these changes.

`radio_button` : | a GtkRadioButton.
`group` : | an existing radio button group, such as one returned from `gtk_radio_button_get_group()`.

### gtk_radio_button_get_group ()

    GSList*     gtk_radio_button_get_group      (GtkRadioButton *radio_button);

Retrieves the group assigned to a radio button.

`radio_button` : | a GtkRadioButton.
Returns : | a linked list containing all the radio buttons in the same group as `radio_button`.

## Properties

### The "`group`" property

      "group"                GtkRadioButton        : Write

Sets a new group for a radio button.

## Signals

### The "group-changed" signal

    void        user_function                  (GtkRadioButton *radiobutton,
                                                gpointer user_data);

`radiobutton` : | the object which received the signal.
`user_data` : | user data set when the signal handler was connected.

## See Also

GtkOptionMenu | Another way of offering the user a single choice from many.