res/xml/smart_forwarding_switch.xml

<PreferenceScreen
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:settings="http://schemas.android.com/apk/res-auto"
        android:key="smart_forwarding_preference"
        android:title="@string/smart_forwarding_title">

      <SwitchPreference
          android:key="smart_forwarding_switch"
          android:title="Smart forwarding"
          android:summaryOff="@string/smart_forwarding_summary_disabled"
          android:summaryOn="@string/smart_forwarding_summary_enabled"
          android:disableDependentsState="true" />

</PreferenceScreen>