In addition to writing the folksy Andy Griffith tune, Hagen penned the themes for The Dick Van Dyke Show, The Danny Thomas Show, I Spy, That Girl, The Mod Squad and Mickey Spillane's Mike Hammer, many for famed TV director Sheldon Leonard.
Hagen composed original music for more than 3,000 episodes during his TV career, which spanned more than three decades.
The composer also was active in the film business, mostly as an arranger and orchestrator for 20th Century Fox. He received a 1960 Oscar nomination (shared with Lionel Newman) as musical director for the Marilyn Monroe film Let's Make Love.
Hagen, who played trombone with the Benny Goodman and Tommy Dorsey orchestras, composed the jazz standard Harlem Nocturne. Written in 1939 for big-band leader Ray Noble, the tune went on to be recorded by Les Brown, Glenn Miller, Stan Kenton, Woody Herman, Ray Anthony and many other bands.