Added info notification, when Color Change G-code is empty and user try to add color change on DoubleSlider.

src/slic3r/GUI/DoubleSlider.cpp

@@ -24,6 +24,7 @@
 #include <boost/algorithm/string/replace.hpp>
 #include "Field.hpp"
 #include "format.hpp"
+#include "NotificationManager.hpp"
 
 namespace Slic3r {
 
@@ -2006,6 +2007,9 @@ void Control::add_code_as_tick(Type type, int selected_extruder/* = -1*/)
     if ( !check_ticks_changed_event(type) )
         return;
 
+    if (type == ColorChange && gcode(ColorChange).empty())
+        GUI::wxGetApp().plater()->get_notification_manager()->push_notification(GUI::NotificationType::EmptyColorChangeCode);
+
     const int extruder = selected_extruder > 0 ? selected_extruder : std::max<int>(1, m_only_extruder);
     const auto it = m_ticks.ticks.find(TickCode{ tick });