diff --git a/panda/src/gui/guiBehavior.h b/panda/src/gui/guiBehavior.h
index 605fafaad6..782bf89834 100644
--- a/panda/src/gui/guiBehavior.h
+++ b/panda/src/gui/guiBehavior.h
@@ -17,9 +17,10 @@ protected:
 PUBLISHED:
   class EXPCL_PANDA BehaviorFunctor {
   public:
+    virtual void doit(GuiBehavior*) = 0;
+  PUBLISHED:
     BehaviorFunctor(void);
     virtual ~BehaviorFunctor(void);
-    virtual void doit(GuiBehavior*) = 0;
   };
 PUBLISHED:
   GuiBehavior(const string&);
diff --git a/panda/src/gui/guiButton.I b/panda/src/gui/guiButton.I
index 49cd64b927..21e669e67a 100644
--- a/panda/src/gui/guiButton.I
+++ b/panda/src/gui/guiButton.I
@@ -234,6 +234,15 @@ GuiButton::get_behavior_functor(void) const {
   return _behavior_functor;
 }
 
+INLINE void GuiButton::set_rollover_functor(GuiBehavior::BehaviorFunctor* f) {
+  _rollover_functor = f;
+}
+
+INLINE GuiBehavior::BehaviorFunctor*
+GuiButton::get_rollover_functor(void) const {
+  return _rollover_functor;
+}
+
 INLINE void GuiButton::set_behavior_event_parameter(int p) {
   this->_have_event_param = true;
   this->_event_param = p;