I was setting up an example of the Hello List tutorial, and I am getting "AutoCompleteTextView cannot be resolved to a type" and "ArrayAdapter cannot be resolved to a type" error messages. This tells me there is a class library I need to import into the program, right? When I try to import android.widget or android.view, those produce errors.

Question: What piece of the development kit am I missing, where do I get it, and how do I make it usable in my development environment?

show us the code...