If you're using stock API classes (no methods to override or implement), there isn't a huge need to create individual files for each. Typically new class files are only created when you new to define a new class or extend an existing one.
It seems the ArrayAdapterClass
extends an Activity
. An Activity
is an individual app screen. You would typically move between Activities by using an Intent
. It seems that your MainActivity
has no way to start the ArrayAdapterClass
.