Complex sorting for search in realm, union of multiple RealmResults

Question

I replaced sqlite with realm in my open source Linux Command Library project. Everything went fine so far, but now I\'m facing a problem.

I\'m using a RealmBaseAdapt

Answer 1

Not sure if there isn't a better/more-performant way for that but you can try making 3 different queries and then concatenating their results.

    List commands = new ArrayList<>();

    commands.addAll(realm.where(Command.class)
            .equalTo("name", query)
            .findAll());

    commands.addAll(realm.where(Command.class)
            .beginsWith("name", query)
            .notEqualTo("name", query)
            .findAll());

    commands.addAll(realm.where(Command.class)
            .contains("name", query)
            .not().beginsWith("name", query)
            .findAll());

This obviously involves changing your Adapter implementation from RealmBaseAdapter to something more regular. Please keep in mind that while your Realm objects reside in a regular list, they still keep a connection to your Realm database, so you can't close your realm instance while your ListView is displaying data.

Update: As @EpicPandaForce pointed out in comments, this solution doesn't work well with Realm's autoupdating. It may appear that some Commands are removed / have changed names and this won't be reflected by your Adapter in that case. Make sure to copy your objects first and setup a change listener on your realm results.