ItemsContentProvider: Move URI constants into Config class.
Convert some class fields into local variables.
ClassifyFragment: Remove getUserId() because it is already in the base class.

And it is not used yet anyway.
ItemActivity: Avoid an android-lint warning.
Layout XML: Some slight corrections.
Use some Java 7 syntax to simplify catch blocks.
Use some Java 7 syntax to simplify new with ArrayList<>.
Remove unnecessary imports.
Layout XML: Remove some invalid parameters, according to android-lint.