Invalidation callback for DataSource.
Used to signal when a DataSource a data source has become invalid, and that a new data source is needed to continue loading data.
Called when the data backing the list has become invalid.
@AnyThread abstract fun onInvalidated(): Unit
Called when the data backing the list has become invalid. This callback is typically used to signal that a new data source is needed.
This callback will be invoked on the thread that calls invalidate. It is valid for the data source to invalidate itself during its load methods, or for an outside source to invalidate it.