As per this post, I know I am allowed to create an activity that has no user interface by declaring your activity like below:
<activity
    android:name=".NoUIActivity"
    android:theme="@android:style/Theme.NoDisplay">
</activity>
My problem is NoUIActivity extends AppCompatActivity. If I use the android:theme line above, it gives me error saying I should use the corresponding AppCompat theme. Help please. Thanks!