After being on the job for 23 years I can say that Adam-12 is the closest thing to real patrolling than anything else on TV, current reality TV shows like "Cops" included.
If you watch Adam-12 you will see many times most of the show is about calls/interactions with the public of the type that happen everyday in America. A kid with his head stuck in a fence, a lady causing a traffic accident because her kid's pet lizard she was transporting in her car is loose. Meeting with merchants who are holding a juvenile for stealing candy. Responding to an accident and having to separate two angry parties who believe "it's not my fault. Pet and Jim sharing a meal, some coffee and talking about things that everyday humans think about - family, finances, boats, motorcycles, the boss.
Although Adam-12 does have more gun action in an episode than is realistic, it still pales in comparison to a "Cops" episode filmed over a three or four month period and condensed down into 30 minutes of constant fights, car chases, shootings, prostitutes, drugs, drunks and on and on.
Many of the younger generation coming into the profession today are shocked at the hours/days of mundane tasks and boredom, punctuated only occasionally by brief seconds of sheer terror now and then. They expect the job to look like "Cops" or "CSI" or "Criminal Minds", and............It's really "Adam-12". As always, YMMV