implement scroll wheel support for ardour-dropdown

diff --git a/gtk2_ardour/ardour_dropdown.cc b/gtk2_ardour/ardour_dropdown.cc
index cd1bfefed35ef71aa1b66675d7b8ad5b9d55f4ce..84c54489ec8a049560cd56eb40c1349f80fe8136 100644 (file)
--- a/gtk2_ardour/ardour_dropdown.cc
+++ b/gtk2_ardour/ardour_dropdown.cc
@@ -63,9 +63,68 @@ ArdourDropdown::~ArdourDropdown ()
 }
 
 bool
-ArdourDropdown::on_button_press_event (GdkEventButton*)
+ArdourDropdown::on_button_press_event (GdkEventButton* ev)
 {
-       _menu.popup (1, gtk_get_current_event_time());  
+       if (ev->type == GDK_BUTTON_PRESS) {
+               _menu.popup (1, gtk_get_current_event_time());
+       }
+       return true;
+}
+
+bool
+ArdourDropdown::on_scroll_event (GdkEventScroll* ev)
+{
+       using namespace Menu_Helpers;
+
+       const MenuItem * current_active = _menu.get_active();
+       const MenuList& items = _menu.items ();
+       int c = 0;
+
+       if (!current_active) {
+               return true;
+       }
+
+       /* work around another gtkmm API clusterfuck
+        * const MenuItem* get_active () const
+        * void set_active (guint index)
+        *
+        * also MenuList.activate_item does not actually
+        * set it as active in the menu.
+        *
+        */
+
+       switch (ev->direction) {
+               case GDK_SCROLL_UP:
+
+                       for (MenuList::const_reverse_iterator i = items.rbegin(); i != items.rend(); ++i, ++c) {
+                               if ( &(*i) != current_active) {
+                                       continue;
+                               }
+                               if (++i != items.rend()) {
+                                       c = items.size() - 2 - c;
+                                       assert(c >= 0);
+                                       _menu.set_active(c);
+                                       _menu.activate_item(*i);
+                               }
+                               break;
+                       }
+                       break;
+               case GDK_SCROLL_DOWN:
+                       for (MenuList::const_iterator i = items.begin(); i != items.end(); ++i, ++c) {
+                               if ( &(*i) != current_active) {
+                                       continue;
+                               }
+                               if (++i != items.end()) {
+                                       assert(c + 1 < items.size());
+                                       _menu.set_active(c + 1);
+                                       _menu.activate_item(*i);
+                               }
+                               break;
+                       }
+                       break;
+               default:
+                       break;
+       }
        return true;
 }
 

diff --git a/gtk2_ardour/ardour_dropdown.h b/gtk2_ardour/ardour_dropdown.h
index b27b930037c7e10cf1eb8162194d85016f9a02f6..c1cf11917e241a8fc1c25af7b117f52050f0f1fb 100644 (file)
--- a/gtk2_ardour/ardour_dropdown.h
+++ b/gtk2_ardour/ardour_dropdown.h
@@ -37,6 +37,7 @@ class ArdourDropdown : public ArdourButton
        virtual ~ArdourDropdown ();
 
        bool on_button_press_event (GdkEventButton*);
+       bool on_scroll_event (GdkEventScroll*);
 
        void clear_items ();
        void AddMenuElem (Gtk::Menu_Helpers::MenuElem e);