Can I have a widget and sidebars in custom theme?

Wordpress 4.1.1: simular problem to another question: I have a add_action widgets_init call back in which I have a call to register_widget that registers a class and a call to register_sidebar that registers some sidebars. Only the Widget shows. If I comment it out the sidebars show. I can create another callback but with the same results. Can I define a widget and sidebars in a theme?