My whirlpool dryer stoppoed working while I was drying some tennis shoes. The drum belt is fine the door and timer appear to but working well. The heat even turns on so the breaker is working. Any ideas?

You have me confused. Is the dryer working now? Was your question why did it stop in the middle of the cycle? Because you should not have heat if it is not turning right now. If you question is why did it stop mid cycle it would be because your tennis shoes wanted out of the hot dryer and they kicked the door and the door switch momentarily opened shutting off the dryer. You need to tell me what it is not doing right now if you are having a problem i.e. It won't start.