Given to the ringtone picker as a Android.Net.Uri. The Android.Net.Uri of the ringtone to play when the user attempts to preview the "Default" ringtone. This can be one of NoType:android/provider/Settings$System;Href=../../../reference/android/provider/Settings.System.html#DEFAULT_RINGTONE_URI, NoType:android/provider/Settings$System;Href=../../../reference/android/provider/Settings.System.html#DEFAULT_NOTIFICATION_URI, or NoType:android/provider/Settings$System;Href=../../../reference/android/provider/Settings.System.html#DEFAULT_ALARM_ALERT_URI to have the "Default" point to the current sound for the given default sound type. If you are showing a ringtone picker for some other type of sound, you are free to provide any Android.Net.Uri here.