* GActionEntry:
* @name: the name of the action
* @activate: the callback to connect to the "activate" signal of the
- * action
+ * action. Since GLib 2.40, this can be %NULL for stateful
+ * actions, in which case the default handler is used. For
+ * boolean-stated actions with no parameter, this is a
+ * toggle. For other state types (and parameter type equal
+ * to the state type) this will be a function that
+ * just calls @change_state (which you should provide).
* @parameter_type: the type of the parameter that must be passed to the
* activate function for this action, given as a single
* GVariant type string (or %NULL for no parameter)
* @state: the initial state for this action, given in GVariant text
* format. The state is parsed with no extra type information,
* so type tags must be added to the string if they are
- * necessary.
+ * necessary. Stateless actions should give %NULL here.
* @change_state: the callback to connect to the "change-state" signal
- * of the action
+ * of the action. All stateful actions should provide a
+ * handler here; stateless actions should not.
*
* This struct defines a single action. It is for use with
* g_action_map_add_action_entries().