Add API to set select item from ArdourDropdown

This fixes an issue with scroll-wheel control which uses `get_active()`.
It work around an issue with gtkmm:

 const MenuItem* get_active () const
 void set_active (guint index)

and MenuList::activate_item() not emitting activate_item().

2 files changed, 18 insertions, 1 deletions

diff --git a/libs/widgets/ardour_dropdown.cc b/libs/widgets/ardour_dropdown.cc
index 321992d632..822d1fdb26 100644
--- a/libs/widgets/ardour_dropdown.cc
+++ b/libs/widgets/ardour_dropdown.cc
@@ -80,6 +80,22 @@ ArdourDropdown::on_button_press_event (GdkEventButton* ev)
 	return true;
 }
 
+void
+ArdourDropdown::set_active (std::string const& text)
+{
+	using namespace Menu_Helpers;
+	const MenuList& items = _menu.items ();
+	int c = 0;
+	for (MenuList::const_iterator i = items.begin(); i != items.end(); ++i, ++c) {
+		if (i->get_label() == text) {
+			_menu.set_active(c);
+			_menu.activate_item(*i);
+			break;
+		}
+	}
+	set_text (text);
+}
+
 bool
 ArdourDropdown::on_scroll_event (GdkEventScroll* ev)
 {
diff --git a/libs/widgets/widgets/ardour_dropdown.h b/libs/widgets/widgets/ardour_dropdown.h
index 9f88c84a38..8b62d7e27a 100644
--- a/libs/widgets/widgets/ardour_dropdown.h
+++ b/libs/widgets/widgets/ardour_dropdown.h
@@ -51,9 +51,10 @@ public:
 	Gtk::Menu_Helpers::MenuList& items () { return _menu.items (); }
 
 	void append_text_item (std::string const& text);
+	void set_active (std::string const& text);
 
 protected:
-	void default_text_handler (std::string const& text);
+	void default_text_handler (std::string const&);
 
 private:
 	Gtk::Menu      _menu;