[PATCH] add the binding friendly join_group method to GtkRadioAction

* Due to object ownership issues it is impossible to correctly use
  get_group/set_group from a GI binding
* join_group is safer because at the binding level it works with individual
  GtkRadioAction objects and not with the list of objects that gets
  modified in the library

1 files changed, 55 insertions, 0 deletions

diff --git a/gtk/gtkradioaction.c b/gtk/gtkradioaction.c
index d6363ed1e1..f44c2b546c 100644
--- a/gtk/gtkradioaction.c
+++ b/gtk/gtkradioaction.c
@@ -469,6 +469,61 @@ gtk_radio_action_set_group (GtkRadioAction *action,
 }
 
 /**
+ * gtk_radio_action_join_group:
+ * @action: the action object
+ * @group_source: (allow-none): a radio action object whos group we are 
+ *   joining, or %NULL to remove the radio action from its group
+ *
+ * Joins a radio action object to the group of another radio action object.
+ *
+ * Use this in language bindings instead of the gtk_radio_action_get_group() 
+ * and gtk_radio_action_set_group() methods
+ *
+ * A common way to set up a group of radio actions is the following:
+ * |[
+ *   GtkRadioAction *action;
+ *   GtkRadioAction *last_action;
+ *  
+ *   while (/* more actions to add */)
+ *     {
+ *        action = gtk_radio_action_new (...);
+ *        
+ *        gtk_radio_action_join_group (action, last_action);
+ *        last_action = action;
+ *     }
+ * ]|
+ * 
+ * Since: 3.0
+ */
+void
+gtk_radio_action_join_group (GtkRadioAction *action, 
+			     GtkRadioAction *group_source)
+{
+  g_return_if_fail (GTK_IS_RADIO_ACTION (action));
+  g_return_if_fail (group_source == NULL || GTK_IS_RADIO_ACTION (group_source));  
+
+  if (group_source)
+    {
+      GSList *group;
+      group = gtk_radio_action_get_group (group_source);
+      
+      if (!group)
+        {
+          /* if we are not already part of a group we need to set up a new one
+             and then get the newly created group */  
+          gtk_radio_action_set_group (group_source, NULL);
+          group = gtk_radio_action_get_group (group_source);
+        }
+
+      gtk_radio_action_set_group (action, group);
+    }
+  else
+    {
+      gtk_radio_action_set_group (action, NULL);
+    }
+}
+
+/**
  * gtk_radio_action_get_current_value:
  * @action: a #GtkRadioAction
  *