An electronic device may have a housing with an opening. A button may be formed within the electronic device. The button may have a button member that is actuated by a user. The button member may translate within an opening in the electronic device housing when actuated by a user. The button may have a shaft that is coupled to the button member by a coupling mechanism. When the button member is laterally translated within the opening, the coupling mechanism may rotate the shaft about its longitudinal axis. The button may be provided with detents using a detent biasing mechanism. The detent biasing mechanism may be based on a spring having grooves that interact with a protrusion on the shaft or a spring-loaded pin that engages recesses in the shaft. A switch mechanism for the button may be formed using traces on the shaft, spring-type switch contacts, and other structures.