Common Event on weapon equip?

Is there a way to run an event when equipping a weapon? I found the weapon can have common event attached but since it's in the effects list I guess it only runs when you use the weapon. I was thinking of system where equipping the weapon changes the class so I'd need to run handful of event commands on such occasion. I did find Yanfly plugin that would let me run an event when menu is closed but I'd like to get the class change effects to come into action while still in menu (if that's possible otherwise).