Sacramento police said the motion picture "RoboCop" so fascinated a robbery suspect that he continued watching in the front row while police evacuated 14 other patrons from the theater, preparing to take him into custody. Officers finally got the man's attention when they turned on the lights. Alphonso Hayden Jr., 25, of Sacramento, was arrested on suspicion of robbing Sacramento Savings & Loan Assn. in the shopping mall where the theater is located. Police said Hayden was a few yards outside the savings and loan office when an explosive charge released a cloud of red dye that coated the cash--and him. He ducked into the theater, where he tried to flush the stained money down a toilet, tore off his reddened shirt and sat down to watch the movie.