Sets the filter for the group.
- iOS 4.0–9.0Deprecated
The filter for the group.
This method sets the filter the group; it does not execute the filter. The filter is applied when you invoke
number or enumerate the contents.
If you don’t set the filter, or set it to
nil, the enumeration returns all the assets in the group.
Only one filter is active at a time. Any enumeration currently in flight continues to completion using the previous filter.