open-keychain/OpenPGP-Keychain-API/example-app/src/main/res/xml/base_preference.xml

<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">

    <PreferenceCategory android:title="OpenKeychain Intents">
        <Preference
            android:key="intent_demo"
            android:title="Intent Demo" />
    </PreferenceCategory>
    <PreferenceCategory android:title="OpenPGP Provider API">
        <org.openintents.openpgp.util.OpenPgpListPreference
            android:key="openpgp_provider_list"
            android:title="Select OpenPGP Provider!" />
        <Preference
            android:key="openpgp_provider_demo"
            android:title="OpenPGP Provider Demo" />
    </PreferenceCategory>

</PreferenceScreen>