What is the test for the Fourth Amendment contention?

"We advert, first, to the Fourth Amendment contention. The main thrust of defendant's argument is that the police officers had no right to intrude on his reasonable expectations of privacy by listening at the door of the locked apartment for an extended period of time with the hope that someone might open the door. The basis for this contention is the holding in Katz v. United States, 389 U.S. 347, 88 S.Ct. 507, 19 L.Ed.2d 576 and People v. Edwards, 71 Cal.2d 1096, 80 Cal.Rptr. 633, 458 P.2d 713.