Changing to androidx - Ringtone Preference

I'm in the process of switching over to androidx libraries from the android support libraries. I previously had a Preferences screen,

Using the androidx preferences manager, I'm doing this. PreferenceManager.setDefaultValues(this, R.xml.battery_preferences, false);

But I get an exception indicating Caused by: java.lang.ClassNotFoundException: androidx.preference.RingtonePreference. I see that the native RingtonePrefernece is deprecated, but there also doesn't seem to be an anroidx Ringtone Preference?

<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"
                  android:title="@string/pref_network_category">
    <PreferenceCategory android:title="@string/my_tittle_1">
        <RingtonePreference
                android:title="@string/title1"
                android:summary="@string/sum1"
                android:key="@string/soundKey1"
                android:showDefault="true"
                android:showSilent="true"
                android:ringtoneType="notification"
                android:defaultValue="content://settings/system/notification_sound"/>

              ....
    </PreferenceCategory>
</PreferenceScreen

I'm using 'androidx.preference:preference:1.1.1',