Close #Iss218

I made a few variables that should actually remain private public. If the solution is OK, I am going to resolve that using getters / setters etc. but I wanted you to have a look first because I am not quite sure if it is a good idea to "connect" those classes.
Indeed, there should be no need to handle both cases here, because the conversion from circle to arrow button is one way only and should always result in an untoggled button, i.e. a "down" arrow.