[gtkmm] ComboBox: set_active_id(): Add documentation.

[Murray Cumming <murrayc src gnome org>]

commit a8b6356c9cf3ce3717e46ad5c01a3e846e429077
Author: Murray Cumming <murrayc murrayc com>
Date:   Tue Oct 9 20:43:11 2012 +0200

    ComboBox: set_active_id(): Add documentation.
    
            * gtk/src/combobox.hg: Add documentation so we can use our own
    @newin{} line.

 ChangeLog           |    7 +++++++
 gtk/src/combobox.hg |   12 ++++++++++++
 2 files changed, 19 insertions(+), 0 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index cdc165c..6fb8e31 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 2012-10-09  Murray Cumming  <murrayc murrayc com>
 
+        ComboBox: set_active_id(): Add documentation.
+
+        * gtk/src/combobox.hg: Add documentation so we can use our own
+	@newin{} line.
+
+2012-10-09  Murray Cumming  <murrayc murrayc com>
+
         ComboBox: Add set_active_id(), deprecating get_active_id(string).
 
         * gtk/src/combobox.hg: We just got the name wrong before, calling it
diff --git a/gtk/src/combobox.hg b/gtk/src/combobox.hg
index 99fb2b4..77f9e08 100644
--- a/gtk/src/combobox.hg
+++ b/gtk/src/combobox.hg
@@ -189,6 +189,18 @@ public:
   _WRAP_METHOD(void set_id_column(int id_column), gtk_combo_box_set_id_column)
   _WRAP_METHOD(Glib::ustring get_active_id() const, gtk_combo_box_get_active_id)
   _WRAP_METHOD(void get_active_id(const Glib::ustring& active_id), gtk_combo_box_set_active_id, deprecated "Use set_active_id(). This method was incorrectly named.")
+
+  /** Changes the active row of the combo box to the one that has an ID equal to
+   * @a active_id.
+   *
+   * If property_id_column() is unset or if no row has the given ID then the function 
+   * does nothing and returns false.
+   *
+   * @param active_id The ID of the row that should be set to active.
+   * @returns true if a row with a matching ID was found.
+   *
+   * @newin{3,6}
+   */
   _WRAP_METHOD(bool set_active_id(const Glib::ustring& active_id), gtk_combo_box_set_active_id)
 
   _IGNORE(gtk_combo_box_append_text, gtk_combo_box_insert_text, gtk_combo_box_prepend_text, gtk_combo_box_remove_text, gtk_combo_box_get_active_text) //deprecated