In the image, you can see the Tag/Layer tool selected, alongside a toolbar showing all the SketchUp validation states available in https://ruby.sketchup.com/UI/Command.html#set_validation_proc-instance_method
In my extension, some tools have the same behavior as native SketchUp tools, depending on how the user launches them.
Can someone clarify how toolbar icon appearance works?
test_menu_states_loader.rbz (3,3 Ko)
