To interact with a Button or TextView from alvin2.xml :

@Override protected void onCreate(Bundle savedInstanceState) super.onCreate(savedInstanceState); setContentView(R.layout.alvin2); // Note: no .xml extension

It seems you are looking for a guide related to in the context of Android development.

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> <TextView android:id="@+id/textView1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Hello from Alvin2" />

Based on common Android patterns, alvin2.xml is almost certainly an (located in res/layout/ ). There is no standard Android file by this name, so it is likely a custom file from a specific tutorial, project, or book (possibly "Alvin 2" as a sample name).

@Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) return inflater.inflate(R.layout.alvin2, container, false);