Reference to a drawable resource to use for the frame. If not given, the drawable must be defined by the first child tag.

Must be a reference to another resource, in the form "@[+][package:]type:name" or to a theme attribute in the form "?[package:][type:]name".

[Android Documentation]

Namespace: Android
Assembly: Mono.Android (in Mono.Android.dll)
Assembly Versions: 0.0.0.0
Since: Added in API level 1