← Lecture 2 DemosDEMO 01 · APP STRUCTURE
SEPARATION OF RESPONSIBILITIES

Who is responsible?

Select a part of the application. The same app needs four different kinds of work.

APPLICATION PARTSSELECT ONE
WHY THIS PART EXISTSactivity_main.xml

Layout defines the interface

It places the Spinner, Button, and TextView. It should not decide which beer brands to recommend.

Change the layout and the screen changes. The recommendation rules stay the same.