onClick ID with Class

I have an object with the class active and another class achievementsIndicator. The active part of the class is something that i add and remove, so it is not static. What i want is a function to fire when you click the object and the active class is on. Here is some to clarify a bit better what i want to achive, this is how i imagined it:

$(.achievementsIndicator.active).onclick(function(){ ...function goes here...  })